Information

What species of spider is this? Could anyone help


This image was taken in assam, India. The size was around 1cm. Could anyone help identify?


This is a male Carrhotus sannio (the females are brown/grey). The white dorsal stripe on the cephalothorax is right beneath the outside eye; the upside-down v-marks on the back of the abdomen point to two white lines (sometimes broken) which run parallel to the length.

Gallery of males: https://inaturalist.ca/taxa/334660-Carrhotus-sannio/browse_photos?quality_grade=any&term_id=9&term_value_id=11


It looks like Adanson House Spider, Hasarius adansoni. From the eyes, it's definitely a salticid, and the reported 8mm size for females is close to the 1cm you estimated for yours. Here's an image from spiderid.com with similar markings:


Spiderman meets Spider-Man

World expert arachnologist Norman Platnick sits down with Dr. Biology to talk about his favorite eight legged animal. Sometimes scary to people, learn what the world might be like without spiders and if the current action hero Tobey Maguire is actually afraid of the animal who made him famous.

Topic Timecode
Intro 00:00
How did you get interested in spiders? 01:17
How many species of spiders are in the world? 01:58
How many spiders species are left to be discovered? 02:08
The number of spiders you have discovered. 02:23
How many spiders are dangerous to humans? 03:19
How many species of spiders in the U.S. that are dangerous to humans? 04:29
Black widow bytes misdiagnosed as an appendicitis. 05:03
Brown recluse spider 05:22
So spiders are not that dangerous for humans and are critical to the planet. 06:08
What if there were no spiders on Earth? 06:47
Why do you think people are afraid of spiders? 08:22
What are some of the best things about spiders - what are some of your favorite spiders? 09:20
What are some of the coolest characteristics of spiders - silk - types - strength. 10:43
SPIDA-web - artificial neural network 12:18
SPIDA-web learns? 13:44
Can anyone use SPIDA-web? 14:22
How was SPIDA-web funded and how much did it cost? 16:10
Other spider resources on the web. 17:30
What's it like to work in a natural history museum - American Museum of Natural History? 17:58
Spiderman meets Spiderman - is Tobey Maguire afraid of spiders? 19:12
What's an average day like for you? 19:52
Travel as part of your job. 21:26
Do you have any interesting travel adventure stories? 21:49
Launch of the new International Institute for Species Exploration - what do you hope the IISE will do? 22:26
When did you know you wanted to be a biologist - scientist? 24:36
What would you be if you were not a biologist? 25:44
The importance of artists in science. 26:40
What advice do you have for someone wanting to become a biologist? 27:33
Sign-off 28:10

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Dr. Biology: This is "Ask a Biologist," a program about the living world, and I'm Dr. Biology.

If I was to ask you, “Who’s Spiderman," I bet most of you would answer, "Peter Parker." While the Marvel comic hero is likely more well known than our guest today, he's just fiction, and our guest scientist is real. OK, our guest is also not wearing a superhero costume, and he didn't swing into the studio on a strand of silk.

Instead, Dr. Norman Platnick is possibly one of the most well known arachnologists in the world. You might be thinking "Arachno what?" In case you're not up on your Latin, "arachno " means spider and " ologist," just like the ending of "biologist," means "the study of." So, Dr. Platnick studies spiders. And even though he does not have spidey senses, he does have "SPIDA web", an artificial neural network used by scientists to identify spiders around the world at superhuman speeds.

We're able to talk with him while he's visiting ASU for the launch of the new International Institute for Species Exploration, which we'll talk about a bit later. Welcome to the show, Dr. Platnick.

Norman Platnick: Thanks, great to be here.

Dr. Biology: Now, your first name is Norm or Norman. Do you prefer I call.

Norm: I prefer Norm.

Dr. Biology: You prefer Norm? Great. Spiders, now how did you get started studying and collecting spiders?

Norm: [laughs] Well, I first got interested in spiders because of my wife. We were undergraduates together at a small school in West Virginia in the Appalachian Mountains, and she got very interested in millipedes, which are really beautiful in those areas. They're big, very colorful, every mountain has different species.

We'd go in the field and look for these things. When they're disturbed, millipedes emit defensive secretions that include cyanide gas, and they smell a little bit like maraschino cherries. If you've got a good nose, you can collect millipedes real well, but we'd get back to the lab and there'd be nothing in my jar but spiders. So I started looking at them and just never stopped. Dr. Biology: How many species of spiders are in the world?

Norm: Well, there are a little bit over 40,000 currently valid species that have already been described by scientists.

Dr. Biology: Forty thousand, all right. And how many do you suspect are still out there to be discovered?

Norm: Well, that's an open question and people have different opinions on it. I've spent a bit of time looking at the arguments. I think we're about halfway there. I think about another 40,000 remaining to be discovered.

Dr. Biology: About another 40,000. That's pretty impressive, because you gave a wonderful lecture last evening, and you had a list of people that are other spider experts. And if I recall and it was getting late in the evening and it had been a long day you're a little bit under 2,000 of those species you actually discovered or named or classified?

Norm: Well, those are species which I newly described. So, I was the first person to describe them. But that's actually just a small part of what I do, because most of my work is spent trying to find out what the previously described species are. So, we have a legacy that's gone on for about 250 years of scientific work on the group, and it's just as important to be able to figure out what species are already known as well as to describe the new ones. Dr. Biology: Right. But if there are 40,000 species out there and you've done roughly 2,000, a little bit under that, that's about five percent, right?

Norm: I suppose so, yeah.

Dr. Biology: Well, that's pretty impressive. How many of those do you think are dangerous for humans?

Norm: Well, very few, actually. Almost all spiders have venom, but that's a long way away from being dangerous to a person. Most spiders are so small that they couldn't break your skin if they tried to bite you. So, you can get rid of about half of them that way.

Of the ones that are large enough and powerful enough to break your skin, if you got bitten, in most cases the venom would have absolutely no effect on you whatever. The venom has evolved over hundreds of millions of years to work on insects. If it has an effect on a human or another mammal or any vertebrate, that's actually an accident of biochemistry. It's just an accidental effect that the venom has an effect because, let's face it, we don't look like prey. We don't look like food to spiders.

So, the venom is generally completely harmless. There are a few exceptions, of course. First off, just like with a bee sting, some people can be allergic to an individual venom or a component, some part of venom. And that happens rarely. And then there are very few species which have venom that actually is harmful.

Here in the U.S. there are really only a couple of species that are of any concern. Most people have heard of them. You have black widows. They are easily recognized, they have a round black abdomen and a red hourglass mark on the bottom of the abdomen. And you should treat them with respect. The venom is not generally fatal. In any case where venomous spiders bite humans, it's children and elderly and ill people who are at the greatest risk. Children, of course, because they get the same amount of venom, the body is smaller, so it has a larger effect.

With things like black widow bites you have to sometimes be careful because doctors can misdiagnose them. They may think you have appendicitis, treat you for that, and of course that's doing no good for the actual cause.

Dr. Biology: I didn't know that.

Norm: Yeah, it happens rarely. But there are few if any fatalities from that venom. The other kind of spiders which we have in the U.S. that are dangerous are the brown recluse spiders, and they have a very different kind of venom that actually destroys tissue. So, if you get bitten, you can lose quite a bit of tissue around the bite site, and that can be very unpleasant.

But again, neither of these spiders are aggressive. You're only likely to be bitten if they happen by accident to get in your clothes, or in your bedding and you roll over on them, and you're crushing them and they have no way to escape. And as a last resort they may bite. Much like as with snakes, humans are generally loud and noisy, and the spider hears you and it's long gone before you're in its path.

Dr. Biology: Right. It's interesting, you talk about it's by accident. The only time I've ever been bitten by a bee, for example, is when I rolled over on it. Well, what I'm getting at with the spiders and it's kind of a roundabout way is the fact that spiders are really not that dangerous to humans. In fact, they're really important to humans as well as all of life on Earth.

Norm: Oh, absolutely. Spiders are predators, they eat only live prey that they catch themselves, and they eat phenomenal amounts of insects. And they are in fact the dominant predators of insects, and without them we'd be in dire straits. In many cases most of our crops, for example, would be totally destroyed by the insects that already do take a large toll on our crop production, but the spiders help control them.

Dr. Biology: So, let's expand this a little bit further. What if there were no spiders on Earth, what would the world be like? Would many of the other living things still be here? Would we even be here?

Norm: I'd say it's questionable whether we would be here. Spiders can occur in amazing numbers and densities in some areas, so much so that people try to use them purposefully to control insect pests. They're not ideal for that purpose, because most spiders are generalist feeders. They'll eat anything they can come across. They're not going to separate one particular species of insect and just eat that the way you might want to control that insect.

But because of the vast amounts of insects they consume, they are a crucial part of the ecosystem, and a lot of things would change if they weren't here.

Dr. Biology: I get a really hard time from my wife and children because when I find spiders it doesn't matter what kind of spider in the house, I get a cup and a piece of paper and I'm always capturing them and taking them outside. And they always laugh at me for doing this, but I am really rather passionate about these animals. They really aren't there to harm me, and I do know they're trying to get rid of a lot of the other insects that we wouldn't want in the house.

Norm: Yeah, but my first question would be, why are you taking them out of the house? Do you want more insects inside the house? The spiders are there eating mosquitoes, helping you out.

Dr. Biology: I had a feeling you were going to say that. Well, actually I take them outside because my wife and children would probably step on them.

Norm: I understand.

Dr. Biology: Right, so they're safer outside in this case than they are in my house. And hey, what the heck, they won't be in my bed and I won't accidentally get bitten.

Norm: True enough.

Dr. Biology: And they won't get crushed.

Norm: Right.

Dr. Biology: Why do you think people are afraid of spiders?

Norm: It's very difficult to say. I think a lot of it is cultural. I think it's something that kids pick up from their parents. I think most kids, until they've picked it up from their parents, are more curious than frightened. But spiders can move quickly. They can't move quickly for long distances, but they're good sprint runners, and they can be hairy.

And I think when you see a thing moving very quickly out of the corner of your eye, you have an instantaneous reaction, but it's not rational to be scared of a spider. It's thoroughly rational to be scared of snakes, especially in some parts of the world where a pretty high proportion of snakes can actually harm you. Most spiders can't harm you in any way, and so being afraid of them just doesn't make sense.

Dr. Biology: Right. And not that we're going to be able to change a lot of people's minds by just listening to the show, but I hope they'll at least think, "Well, maybe I'll capture that spider and take it outside."

Norm: Absolutely. And consider letting it stay inside and control the insects for you.

Dr. Biology: Well, let's move along to the best things about spiders, because that's really why we have you here. What I'd like to know is what are some of your favorite spiders?

Norm: Well, usually it happens to be just the group of spiders that I'm working on at the moment, because they're so diverse. There are so many different kinds. They are all so poorly known. I've been doing this for about 35 years now. One of the things that makes it exciting and fun is every day I get to come in and look at something that no one's ever seen before. Anf that's really cool.

Right now I'm working on a group of spiders that is very poorly known, probably the most poorly known group, and that's because they are very, very small. They are mostly under two milimeters., so that means you could put about 15 of them head to toe and still not fill up an inch. They're really small animals. But they are amazingly intricate. They do all kinds of things that other spiders don't do.

Dr. Biology: Such as?

Norm: Wow. Many of them have very peculiar modifications on the body. Generally, most spiders have a pretty soft abdomen. For example, lots of people like to keep tarantulas as pets, for example, and you have to be careful that they don't fall. Their abdomens are so soft that if they fall off the table they can actually rupture their abdomens and the animal will die.

These little small goblin spiders, they are called, are very tiny, often have extremely hard and highly ornamented abdomens. Every species is quite different.

Dr. Biology: What are some of the coolest characteristics of spiders?

Norm: Well, the thing that they are most known for, of course, is the silk. Everyone identifies spiders with silk, but it is important to remember that not all spiders spin webs to catch prey. In fact, only about half of them use a web to catch prey.

Of course they are some of the ones we notice most obviously, especially the ones that build very geometrically regular or webs that everyone is familiar with. But all spiders have silk glands and spinnerets. They all use the silk in at least some ways.

Spiders wrap their eggs in silk, for example. Most spiders lay a dragline behind them as they go. That's why if they fall off a branch, they can just climb back up the dragline of silk they left behind. So there are a variety of silks and an individual spider can have seven different kinds of silk glands in its body and produce seven different kinds of silk with different properties, that are used for different things.

Dr. Biology: That's fascinating! I didn't know that. I figured silk is silk.

Norm: No, there are lots of different kinds.

Dr. Biology: Well, that's great! How strong is silk?

Norm: Actually, silk has a tensile strength that's greater than steel. What that means is you can pull it out to a very fine fiber, as it is in any web. That fiber is actually stronger than steel of the same diameter, in the sense that it can be stretched more without breaking.

Dr. Biology: Hmm. Now is spider silk the same as silkworm silk?

Norm: No. They are similar, chemically, but there are differences and there are differences between spiders and differences in the silks produced by a single spider, chemical and physical differences, as well.

Dr. Biology: Hmm. OK well, earlier we talked about even though you don't have Spidey senses, you have SPIDA Web, and it's an artificial neural network that you actually have been working with a team of scientists that have designed it, built it and you are using this computer system. So people don't think you are walking around with this neural network in your head.

You have your own, but this one is a computer one helping people identify spiders. And I'd like you to talk a little bit about SPIDA web.

Norm: OK. One of the problems you have as you can imagine any group that is as diverse as spiders. if you've got 40,000 species, there aren't very many people who know how to distinguish those species.

Often ecologists, for example, people who are studying how spiders interact with other groups in a particular environment, need to be able to identify the animals. In fact, not just the spiders, but all the animals and the plants in the communities that they are studying.

But those people aren't trained, obviously, as spider specialists, and it's very difficult to identify a species of spider or almost any other living organism without having that kind of training.

So what we have tried to do with SPIDA web is develop a system that trains computers to recognize individual species by showing them lots of photographs of a particular species and photographs of other species so that the computer learns to distinguish one species from the others.

Dr. Biology: So it's learning. That's pretty cool.

Norm: It's learning in an artificial sense. That's why they are called artificial neural networks, but it's very much analogous to the way that nerve cells work in your own brain. They receive and they transmit signals. That's the same thing the networks do.

So what we do is take a photograph and then use some techniques to get the information from the photograph into the computer as, obviously, a string of numbers, because that's what the computers understand, and then allow the computer to distinguish between the training sets, the pictures that belong to one species and pictures that don't.

Dr. Biology: Well, I'm not an arachnologist, so I couldn't identify very many species of spiders. I'd have to say I'm a novice.

Norm: OK.

Dr. Biology: Could I go on to SPIDA web and identify a spider?

Norm: Absolutely. What we have up there is basically the first system, so it only covers spiders of one family, which are not found, actually, in the U.S. So it's not going to be particularly helpful to you right here.

But this is a prototype system and basically we have designed it so that it can be used for any group of organisms, not just other groups of spiders, but any group of organisms that you can identify visually, the computer can also be trained to identify from photographs.

So, yes, if you go to the website, you'll find instructions on what parts of the spiders you have to photograph. You submit those photographs across the Internet and within a few seconds you get an identification back.

Dr. Biology: That's just fabulous! Let's figure out what we could do here. All right. How about students and classrooms, once the prototype is perfected, so to speak, and you move on to other kinds of species, could they use it?

Norm: Oh, absolutely. You're obviously talking about something that requires a huge amount of resources to train if you want to cover all the species on the planet. We have no idea how many species of organisms there are on the planet.

We know that there are somewhere around two million already described and estimates of how many there are range from. anywhere from five to 10 or even 30 million. Obviously, it would take a lot of photographs to train networks to recognize all the species, even those that have already been described.

And it might not work for all groups. I mean, for example, if you get microorganisms, you're not going to be able to just go out in the field and take a picture of them with your digital camera and get an answer. But for lots of things it will.

Dr. Biology: This is a prototype. How did you get the money to do this?

Norm: We've actually got a grant for this from the National Science Foundation, which is the primary source of funding for what we call "pure research" in the U.S.

Dr. Biology: And how much money did it take to make the prototype?

Norm: That was about an $800,000 investment. The team had to involve computer scientists. In fact, the primary computer scientist on the project was one we had to hire away from IBM to do this project. That took money. Dr. Biology: You know, it's interesting. We just had a show recently called "Math Biology" and I had two young mathematicians. They are actually an undergraduate and a graduate student. They are blending math and biology and that was one of the questions: What can you do if you have a degree in math and biology? Lo and behold, here you are. We're talking about here's another place that they would fit perfectly.

Norm: Oh, absolutely.

Dr. Biology: And if I recall from the lecture last night, they get paid handsomely, too.

Norm: Computer scientists tend to be very well paid, much in the same way that geologists often tend to be paid more than comparable scientists, simply because there are commercial applications for their work.

In the geologist's case, the oil industry, and in the computer science case, obviously, the entire business world, which can use their skills and is willing to pay for it at levels that are higher than the normal college or university operation can afford.

Dr. Biology: If they are getting excited about spiders. I love seeing cool pictures. Can you recommend or talk about any other resources on the web that people might go to?

Norm: Wow. There are lots of sites dedicated to spider pictures. One of the easiest ways to find them would be to Google the International Society of Arachnology, which has a website and lots and lots of links. So lots of people's albums of spider photos.

Dr. Biology: Excellent. You also work in a natural history museum. It's the American Museum of Natural History in New York.

Norm: Right.

Dr. Biology: I don't know if a lot of people have visited natural history museums. I have to say that the one that you work in is probably one of the best in the world. It's just fabulous. And not everyone may think of museums and natural history as exciting. What's it like to work in a natural history museum?

Norm: Oh, it's fantastic. In particular, in my case, being at the American Museum is the best possible place, because we have the world's largest collection of spiders, well over a million specimens. And so it's an ideal place to do research on that group.

But natural history museums, most people know only the public side, the exhibition side. That's important and it's exciting. People come and they see our dinosaurs and they come and they see a live tarantula.

Those things are exciting, particularly in an urban environment like New York City where we are, that may be the only taste of nature that some kids living in New York City get.

The public side is extremely important. But most people don't realize that there is a research side to any major museum as well, and that there are faculty members just like at a university biology department.

Dr. Biology: Has anything recently happened or have you done anything at the Natural History Museum that's out of the norm?

Norm: When the third "Spider Man" movie debuted recently, they had a week of opening ceremonies in New York. So we set up a small exhibit for the public with a lot of tarantulas on view, which attracted a lot of attention.

Toby McGuire, the actor who plays Spiderman, came by the museum and we had question and answer session with a lot of kids. It was loud and chaotic, but it was a lot of fun. I got to put a tarantula on Toby's arm. He was able to show the kids that he wasn't afraid of spiders.

Dr. Biology: Cool! That's kind of like what, Spiderman meets Spider Man?

Norm: That's exactly it.

Dr. Biology: Obviously he didn't have arachnophobia.

Norm: Not at all.

Dr. Biology: What's an average day like for you, if there is such a thing as an average day.

Norm: Well, a good day is one where I get to come in and just go directly to my microscope and start looking at spiders. But in the real world, of course, good days are not necessarily the ones you experience every day.

We have teaching responsibilities. We have students. We have curatorial responsibilities, taking care of the collections, filling loan requests. We send thousands of specimens all over the world every year to other arachnologists in other countries and other institutions who need them to do their work. Dr. Biology: And so, would you say that no two days are the same?

Norm: Oh, absolutely. Because every day that you can get to the microscope, you get to look at a different spider.

Dr. Biology: Right. And you said that it's kind of the thrill of the hunt. I have to say the same thing. I'm a microscopist, so I do mainly cell biology and cell structure, but I also have another little project called a "paper project."

We actually explore historic and contemporary handmade papers. And you'd be surprised at something the size of a period at the end of a sentence, the beauty that is in there. Seeing things that a lot of people have never seen.

Norm: Right.

Dr. Biology: And that's where you are actually more than a scientist. I think you are an explorer.

Norm: Oh, absolutely. The thrill of the hunt is actually mostly in the field when we do our collecting trips. So, most of my field work, for example, has been done in the south temperate parts of the world, the very far south in Chili and Argentina and South America, in New Zealand and New Caledonia and Australia in the Pacific parts of the world.

Those are the parts of the world which are most poorly known for spiders, so they are the most fun to go to.

Dr. Biology: And you mentioned yet another thing that is very important. I love to travel and it seems like a lot of our biologist guests love to travel. If you are the type of person that likes to travel, maybe science is the place for you.

Norm: Oh, absolutely. It's usually a joke that people who work on spiders and insects are always interested in the spiders and insects that occur at least 3,000 miles from wherever they happen to live.

Dr. Biology: [laughs] Well, tell me, do you have any interesting adventures or stories from your collecting trips?

Norm: Oh, well, I guess the most harrowing one was on the island of New Caledonia in the South Pacific, where I managed to get turned around on the top of mountain. Was walking 180 degrees in the wrong direction. I got quite lost and had an accident and hurt my leg, trying to cross a stream. Spent the night up there waiting for the folks to come find me.

Dr. Biology: OK, that does seem a little bit more exciting than I would have expected. And I hope at least you discovered a new species of spider after all that.

Norm: Oh, absolutely.

Dr. Biology: Well, speaking of travel, you're actually in town. you're here for the launch of a new institute at Arizona State University. It's called the International Institute for Species Exploration. In an earlier show, I actually got to talk about it, I caught up with Quinton Wheeler.

Norm: Terrific.

Dr. Biology: He's the founding director of the IISE. What do you hope this new institute will be able to do?

Norm: Oh, I think it has tremendous potential. Most people certainly, most of the people I encounter outside of science, don't understand how little we know about the organisms that share this planet with us.

Imagine, for example, that if we sent a space craft to Mars and found, for certain, living organisms there. You can imagine that almost immediately, lots more expeditions would be planned, enormous amount of resources would be placed into finding out about this life we have never seen before.

What most people don't realize is that you can go out in your own backyard and have exactly that kind of discovery. You can find things that are not known.

Dr. Biology: Actually we have a researcher here, Bob Johnson, and he did just that. He works with ants. And he discovered a new species of ant in his backyard.

Norm: Not at all surprising. Here in the U.S., for example, we suspect there are about 3,500 species of spiders, and about 300 of them are not yet described.

Dr. Biology: OK, you have heard it here. Now it's time to go hunting for those spiders and not to squish them. And in case you would like to learn more about IISE, it's easy to find on the web.

The address is species.asu.edu. It's got a wonderful site with lots of cool pictures and a gallery that's growing. It's brand new, so there's not a ton of things there, but as time goes on I think it's going to have a lot of really good content, including educational content.

Norm: Right. I think a very important function of the Institute's mission is to make people more aware of the need for learning more about our own planet.

Dr. Biology: All right, we are going to shift into the favorite part of the show for most of the listeners and for myself. I ask three questions. The first question is: When did you know you wanted to be a scientist or a biologist? And I usually think of that spark and it could have been a "eureka." In some people it was slow and gradual, but usually it's something that really triggers in someone's mind.

Norm: Hmm. I guess I first got interested in biology when I was in about the seventh grade. I had a biology teacher who was very interesting and her husband taught biology at a local college. So I got to know him and then sat in some of his classes.

That got me really interested. For a long time I thought I was going to go into genetics. Then, unfortunately, that never happened. I got interested in spiders and that just took off.

Dr. Biology: I think fortunately you got interested in spiders.

Norm: Actually, it is fortunate for me.

Dr. Biology: And it's also interesting. You went to college when you were in seventh grade?

Norm: I finished the seventh grade and then I went into college, yes.

Dr. Biology: Marvelous. Were you a regular student, or were you just having fun sitting in on the classes?

Norm: No. No. I became a freshman, just like any other student. Dr. Biology: Wow. OK. Well, we have words about you.

Norm: [laughter] Precocious, I think, is the only relevant one.

Dr. Biology: Along that line, I'm going to take it all away from you.

Norm: OK.

Dr. Biology: You can't be a biologist. You're not going to be a scientist. You're going to shift. You're going to think, what would you like to be if you couldn't be.

Norm: Well, actually I already have another life so, I don't have to actually shift. I got interested in spiders because of my wife, and for the same reason I got interested in antiques when she did. I've become quite interested in looking at early 20th century American illustrators. So that's my hobby and if I wasn't doing spiders, that's what I would be doing.

Dr. Biology: Early 20th century.

Norm: American illustrators.

Dr. Biology: American illustrators.

Norm: This was at a time before photography was common. So, every magazine that you would see on a newsstand would have reproductions of paintings on the front cover. That's how they sold their magazines. The people who did those illustrations also did postcards and calendars and posters and lots of other illustrations.

It's a fascinating area that was pretty much destroyed when color photography took over.

Dr. Biology: And one of the things during your lecture, and something that comes up over and over again, is the importance of an artist as part of the science process.

Norm: Oh, absolutely. For dealing with most groups of organisms, you can write long descriptions in words, but they don't actually tell another person what they need to know. You need good illustrations. So a skilled artist is essential to making good progress on the science of studying these animals.

Dr. Biology: Right. And even with the ability to do photographs, there's amazing detail and information from those beautiful pen and ink line drawings.

Norm: Oh, absolutely. For every species of spider that gets described today, we try to have lots of kinds of photographs, most importantly, for example, scanning electron microscope photographs. But we also have hand done illustrations because they show details and they show them in a way that makes them more usable.

Dr. Biology: All right, I have one more question: What advice would you have for someone who wants to become a scientist or a biologist, or maybe we hooked someone and they want to get into the study of spiders?

Norm: Wow, that's a tough one. I think most important is to get out into the natural world yourself. To start looking at the animals that you find out there. Spend half an hour watching a spider build its web. Watch a jumping spider catch its prey.

Look at all the different kinds of spiders you can find in one habitat. It's that direct experience with nature that's really going to make the difference.

Dr. Biology: Observations. Yes, I love it. Well, Norman Platnick, thank you for visiting with us today.

Norm: Thanks, it's been a pleasure.

Dr. Biology: You've been listening to "Ask a Biologist." and my guest has been Norman Platnick, who is currently the Peter J. Solomon Curator of Spiders at the American Museum of Natural History.

The "Ask a Biologist" podcast is produced on the campus of Arizona State University. We record our show in the Grassroots Studio housed in the School of Life Sciences, which is an academic unit of the College of Liberal Arts and Sciences.


Terrifying new venomous spider that can live for 20 years discovered at US zoo

A creepy new trapdoor spider that resembles a tarantula and can live for up to 20 years has been discovered in a United States zoo.

See where they live and the first aid treatments that could save a life.

See where they live and the first aid treatments that could save a life.

The spider was first spotted at the zoo in 2012. Picture: Zoo Miami Source:Supplied

A creepy new venomous spider that lives for up to twenty years has been discovered at a Florida zoo.

The Pine Rockland trapdoor spider, or Ummidia richmond, looks like a “small shiny black tarantula” and has a venom that induces a painful sting similar to that of a bee.

The arachnid was first spotted in Zoo Miami in Florida in 2012, but scientists didn’t confirm that it was an entirely new species until this year.

Lurking for decades in burrows, the creepy-crawlies pop out to subdue prey when it crosses their path.

A new type of spider was discovered at Zoo Miami. Picture: Zoo Miami Source:Supplied

“They spend their entire lives in that same burrow, waiting for prey to come past their trapdoor,” Zoo Miami conservation chief Frank Ridgley told the Daily Mail.

“Then they lunge out from their camouflaged lair to grab their prey.”

To a human, a bite from the spider would feel something like a bee sting, according to experts.

The spiders certainly look like miniature tarantulas.

The male Pine Rockland spider is about the size of a quarter, and females are thought to be two to three times bigger.

The females live for up to two decades, while the males typically burrow for about seven years before leaving their shelter to mate.

They die shortly after that.

Dr. Rebecca Godwin, an assistant professor of biology at Piedmont College who published a paper on the new species this month, believes that the spiders that were found in the zoo were “wandering males.”

She also noted that the species is likely limited to “the small area of threatened habitat and subsequently could be threatened itself.”

According to Dr. Godwin, little of the animal’s natural habitat exists outside of Everglades National Park.

The research was published in the journal ZooKeys.

This story was published by The Sun and reproduced with permission.


Synthetic biology and the rise of the 'spider-goats'

F reckles looks like a perfectly normal kid. She has bright eyes, a healthy white pelt and gambols happily with Pudding, Sweetie and her five other siblings, exactly as you might imagine young goats do. Until I fend her off, she's very keen on chewing my trousers. To the casual observer, and to goatherds, she shows no signs that she is not a perfectly normal farmyard goat.

But Freckles is a long way from normal. She is an extraordinary creation, an animal that could not have existed at any point in history before the 21st century. She is all goat, but she has something extra in every one of her cells: Freckles is also part spider.

That is what we can now do with genetics: extreme crossbreeding. If 20th-century biology was about taking living things apart to find out how they work, the current era is defined by putting them back together, but not necessarily as evolution decreed, and certainly without the clumsy constraints of mating. Freckles is the result of genetic engineering. But our mastery of manipulating DNA has evolved into an even more extreme form of tinkering, broadly called "synthetic biology". I've been tracking this emerging field since finishing my PhD in genetics 10 years ago, but intensely in the last year as a presenter for the BBC's flagship science strand, Horizon.

Freckles is the creation of Randy Lewis, a professor of genetics at Utah State University. The farm is a university outpost where they research modern farming techniques, teach animal husbandry and raise what are inevitably referred to as "spider-goats".Randy, like many of the other scientists here in Logan, Utah, has farming in his blood. So although a creature that is part goat, part spider might seem like an idea born of science fiction, as far as Randy is concerned it's simply advanced farming: breeding animals to produce things that we want.

"We're interested in dragline silk – the silk that spiders catch themselves with when they fall," he tells me in his midwest lilt. "It's stronger than Kevlar. It really has some amazing properties for any kind of a fibre."

In a sense, spider-goats are an extension of the farming we've been doing for 10,000 years. All livestock and arable has been carefully bred, each cross being a genetic experiment of its own. "The trouble is, you can't farm spiders," Randy says with an almost comic deadpan face. "They're very cannibalistic." He and his team took the gene that encodes dragline silk from an orb-weaver spider and placed it among the DNA that prompts milk production in the udders. This genetic circuit was then inserted in an egg and implanted into a mother goat. Now, when Freckles lactates, her milk is full of spider-silk protein.

We milk Freckles together and process it in the lab to leave only the silk proteins. With a glass rod, we delicately lift out a single fibre of what is very obviously spider silk and spool it on to a reel. It has amazing, and desirable, properties, which is why Randy's seemingly bizarre research is so robustly funded. "In the medical field, we already know that we can produce spider silk that's good enough to be used in ligament repair," he tells me. "We already know we can make it strong enough as an elastic. We've done some studies that show that you can put it in the body and you don't get inflammation and get ill. We hope within a couple of years that we're going to be testing to see exactly the best designs and the best materials we can make from it."

The instructions for all creatures that have ever lived (as far as we know) are written in the code of DNA tucked away in the heart of living cells. Given the bewildering diversity of life on Earth, this system is incredibly conservative. All life is based on an alphabet of just four letters, which, when arranged in the right order, spell out proteins. And all life is made of, or by, proteins. So what this means is that the code for making silk in a spider is written in exactly the same language as the code for making goats' milk.

Since the advent of genetic engineering, we have been able to exploit the universality of this code and cut and paste bits of DNA from any one species into any other. Identifying the genetic basis of all cancers and inherited diseases came from this technology: human or mouse genes have been spliced into bacteria so we could study and experiment on those damaged bits of code. Now, this editing technology has progressed to the extent that all bits of DNA code are effectively interchangeable between all species. In fact, Freckles and the other spider-goats are not even on the cutting edge. The loosely defined field of synthetic biology has come to incorporate even more extreme forms of genetic tinkering.

The most striking headlines so far came when American biologist Craig Venter announced in 2010 that he had created the world's first synthetic life form. Synthia, aka Mycoplasma mycoides JCVI-syn 1.0, was a cell whose genetic code, copied and modified from an existing bacterium, had been assembled not by its parent, but by a computer. That code, including literary quotations and website addresses, was then jammed into the eviscerated chassis of another similar cell and the whole thing booted up. It did live and it hadn't lived before.

But to say that he had "created life" is a stretch that Venter – a master of PR as well as an accomplished scientist – allowed to foment and the press lapped up. It's more accurate to say that he rebooted life, his aim being to create a living template on to which new genetic functions could be built. Nevertheless, it remains an astonishing technical achievement, showing our dominance over DNA not only can we modify one or two genes, we can make enough to power up a living thing.

The scientists who work in synthetic biology often take a perfunctory, reductionist view of what they do. Massachusetts Institute of Technology professor Ron Weiss is a founding father of this field, a purist who started fiddling with the code of life while coding computers. "I decided to take what we understand in computing and apply that to programming biology. To me, that's really the essence of synthetic biology."

This may sound glib. Life forms are complex at every level. If there is one concrete thing we have learned from the billions spent on reading our own genetic code, it's that biology is messy. Scientists are often confounded by baffling "noise" in the molecules that make up living organisms, unpredictable variation set among unfathomable sophistication. Weiss and his comrades at the BioBricks Foundation want to strip out all the noise in biology and turn it into pure engineering, where organisms can be treated like machines and their inner workings are component parts.

Genes have evolved over millions of years to bestow survival on their hosts by having very specific functions. By standardising these genetic elements in an online registry, anyone can piece them together in any order to create biological circuits with entirely designed purpose. Even the language used is more the stuff of electrical engineering than traditional biology.

"Imagine a program, a piece of DNA that goes into a cell and says, 'If cancer, then make a protein that kills the cancer cell if not, just go away.' That's a kind of program that we're able to write and implement and test in living cells right now." What Ron Weiss is describing is a study his team published last autumn showing that, by using the logic of computer circuits combined with BioBricks parts, they had built a cancer assassin cell. The logic of the genetic circuit initially distinguishes a cancer cell from a healthy cell using a set of five criteria. It then destroys the tumour cell if it satisfied those conditions. This sniper targeting is the opposite of the blunderbuss approach of chemotherapy, which can destroy both tumour and healthy cells with reckless abandon.

Over the last few years, BioBricks has grown into a global phenomenon. The Registry of Standard Biological Parts currently contains thousands of bits of DNA, all freely available, and this democratisation of science is built into the BioBricks ethos. Every year, undergraduate students compete in an international competition to think of a problem and design and build its solution, using only the parts available in the registry. 2011's European champions, from Imperial College London, designed a system for preventing soil erosion and the conversion of land into desert. There is a remix culture within these teams it's serious play (the grand prize is a silver Lego brick) and they come from diverse backgrounds – maths, engineering, even astrophysics – unfettered by the narrowly defined science disciplines under which I did my DNA research.

The ease of access to this bleeding-edge technology is breathtaking. Last summer, in suburban Sunnyvale, California, I hung out at a gathering of synthetic biology weekend hobbyists, self-styled as "bio-hackers" with the excellent name BioCurious. There, high-school students were learning about biology by introducing fluorescent proteins from deep-sea jellyfish into bacteria to make them glow in the dark. In 2009, three scientists won Nobel prizes for this work. Already, it is literally child's play.

As with any great revolutions, there are those who stand to make a killing after the doors are kicked open. At the other end of the scale from the open-source, open-access utopia of BioBricks, synthetic biology commercial enterprises are emerging. The tech may be new, but the fields are not. With synthetic biology only a few years old, the most intense areas of commercialised synthetic biology are in fuel and drug production. California biotech companies such as LS9 and Amyris have ploughed millions of dollars into developing synthetic organisms that will produce diesel. In its futuristic labs in Emeryville, Amyris has modified brewer's yeast so that instead of fermenting sugar to produce alcohol, diesel seeps out of every cell. This synthetic biodiesel is already used to power trucks in Brazil. Amyris's ambition is to scale up from pilot plants to industrial-scale production. When I ask chief science officer Jack Newman if they envisage their biofuel replacing natural oil, he is suspiciously coy: "I'll be excited about a billion litres."

One significant fear has less to do with the science and more to do with the shifting balance of economic power. Technology watchdogs and campaign groups such as Friends of the Earth and ETC Group initially called unrealistically for a total ban on synthetic biology, even though it lacked a workable definition. ETC has modified its stance to focus on the industrialisation of these processes, and specifically the fact that synthetic biodiesel organisms need food.

Jim Thomas, who works for ETC, passionately feels that the control of fuel production is simply shifting from one set of corporate giants to another. "Large companies are buying up bits pieces of land so that they can grow sugarcane and then they're feeding it to vats of synthetic microbes to make fuels," he tells me. "Synthetic organisms at this point should not be out there in the environment they shouldn't be out there in industry. That's irresponsible and inappropriate."

The culture of biology is rapidly changing and scientists and the public need to keep up. Synthetic biology has the potential to generate a new industrial revolution. It is perhaps the defining technology for the 21st century and it is happening now. Without an informed public discourse, fear of this unprecedented and sometimes unsettling technology may hinder the world-changing promise it harbours.

"Prediction is very difficult, especially about the future," as the great physicist Niels Bohr once said. But science fiction never got close to the outlook that came with the advent of synthetic biology. It is now easy to picture a world in which your torn ligaments are replaced with ones made from spider-silk produced by goats where medicine is served by living programmable machines that seek and destroy only the cells that cause the disease and where you will drive a car powered by diesel grown by brewer's yeast. Welcome to the future.


Movers and shakers

That doesn’t mean they’re easy to find. Most of the year, peacock spiders are brown only males gain their striking colors after they molt in the spring. Combine that with their diminutive size, and it’s no surprise studying the non-venomous arachnids can be a challenge.

Watch the amazing dance moves of the peacock spider

That’s why, when identifying a new species, Schubert hones in on the male’s colorations as well as their mating dance, which is unique to each species and involves a male flexing and gyrating to show off its fitness. When Schubert encouraged a male Nemo to dance for a female in the lab, he was surprised by what he found.

This one individual didn’t “lift its abdomen completely like other species, and it doesn’t have those opisthosoma flaps”—which give the spider its famous colorful display—"underneath the abdomen. It’s just got a little brown booty,” explains Schubert. (Read how peacock spiders get such blue abdomens.)

Instead, the male impressed the female by raising its third set of legs and vibrating its abdomen on the ground, generating an audible sound. It’s unknown, he says, whether this is a trademark dance of the Nemo peacock spider.

Schubert noted Nemo’s wetland home is also “really strange,” as the majority of other known peacock spiders prefer dry scrublands.

But peacock spiders are always surprising him. In 2020, scientists found one species, Maratus volpei, living in a salt lake. “We’ve learned that we should be more open to the sorts of habitats where we look for peacock spiders,” Schubert says.

Though peacock spiders play a valuable function as a predator controlling insect populations, there’s still far too little known about their role in the ecosystem and conservation status, he adds.


Even-More-Gigantic Giant Orb Spider Discovered

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Scientists have found the world's largest species of golden orb-weaver spider in the tropics of Africa and Madagascar. The discovery marks the first identification of a new Nephila spider since 1879.

Females of the new species, Nephila komaci, measure a whopping 4 to 5 inches in diameter, while the male spiders stay petite at less than a quarter of their mate's size. So far, only a handful of these enormous arachnids have been found in the world.

"We fear the species might be endangered, as its only definite habitat is a sand forest in Tembe Elephant Park in KwaZulu-Natal," ecologist Jonathan Coddington of the Smithsonian's National Museum of Natural History said in a press release. "Our data suggest that the species is not abundant, its range is restricted, and all known localities lie within two endangered biodiversity hotspots: Maputaland and Madagascar."

The first potential specimen of the new species was uncovered by Coddington and his colleague Matjaz Kuntner of the Slovenian Academy of Sciences and Arts in 2000. They found a huge female orb-weaver among a museum collection of spiders in Pretoria, South Africa, and she didn't match the description of any known spider. Although they hoped the unusual-looking giant represented a new species, several dedicated expeditions to South Africa failed to find any live spiders of a similar description.

Then, in 2003, a second specimen from Madagascar was found at a museum in Austria, suggesting that the first spider hadn't been a fluke. But despite a comprehensive search through more than 2,500 samples from 37 museums, no additional specimens turned up, and the researchers assumed the biggest of all orb-weavers was probably extinct.

Finally, three live spiders have been found to prove the scientists wrong: A South African researcher found two giant females and one male in Tembe Elephant Park, proving that the new species was not extinct, just incredibly rare.

"Only three have been found in the past decade," Kuntner wrote in an e-mail to Wired.com. "None by our team, despite focused searches. Only an additional two exist in old museum collections. Compared to thousands of exemplars of other Nephila species in museums, that is disproportionately rare."

The two biologists named the new species after Andrej Komac, a scientist friend of Kuntner's who died in an accident near the time of the discoveries.

Like all Nephila spiders, females of the new species spin huge webs of golden silk, often more than 3 feet in diameter. In the report of the discovery of this rare spider, published Tuesday in PLoS One, the researchers also addressed the evolution of the dramatic size difference between male and female orb-weavers.

By mapping out the evolutionary tree of all known orb-weaver species, the scientists discovered that as the spiders evolved, females got bigger and bigger, while males stayed roughly the same size.

"It is good for females to be big, because they can lay so many more eggs," Coddington wrote in an e-mail. In addition, large size probably helps females avoid being eaten by predators.

"Relatively few groups can safely pluck an orb-weaving spider from its web," he wrote, "because you have to be able to hover to do so (hummingbirds, wasps, damselflies come to mind). None of these are large enough to tackle an adult Nephila, or even a large juvenile."

Males, on the other hand, are better off staying small and reaching sexual maturity at a young age. Going out searching for a mate is one of the most dangerous activities they undertake.

"So males risk everything to find, probably, just one, huge female, inseminate her, and probably do not willingly leave her web to search for another," Coddington wrote. "Nothing about sex says males must be big."

Image 1: Tiny male Nephila spiders are dwarfed by their female counterparts. Matjaz Kuntner and Jonathan Coddington/PLoS ONE.
Image 2: A giant golden orb-web exceeding 1 meter in diameter, spun by a
Nephila inaurata spider. M Kuntner.


Spider facts

Some commonly asked questions and interesting facts about spiders.

Are huntsman spiders dangerous? They look so large and hairy.

Despite their often large and hairy appearance, huntsman spiders are not considered to be dangerous spiders. As with most spiders, they do possess venom, and a bite may cause some ill effects. However, they are quite reluctant to bite, and will usually try to run away rather than be aggressive. In houses they perform a useful role as natural pest controllers.

Some people may think of huntsman spiders as 'tarantulas'. However, they are not related to the large hairy ground dwelling spiders that are normally called tarantulas. Both huntsman spiders and tarantulas are often portrayed as being dangerous and scary. This usually is the case in films or stories that deliberately present spiders in a frightening and unrealistic way. If you feel frightened of huntsman spiders because of this, perhaps you might like to learn more about their true habits and biology. In this way you might be able to reduce your fears.

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How do you identify a wolf spider?

One of the diagnostic features of wolf spiders is their eye pattern which comprises three rows at the front of the carapace: four (smaller) eyes in the first row, two above the first and two above the second row. The diagram below (basically) shows this layout, face-on to the spider:

Wolf spiders also have a variegated pattern on their bodies, often including radiating lines on the carapace and scroll-like patterns on the top of the abdomen. The underside of the spider is grey or black, sometimes with white markings. They can have orange spots on the sides of their jaws.

As wolf spiders actively hunt for food they are likely to be found roving along the ground and they are more active at night. When spotlighted at night wolf spider's eyes will glow green. Scientists use this method during invertebrate surveys.

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Does Australia have a bird-eating spider?

The term ɻird-eating spider' usually refers to large spiders from the family Theraphosidae. These spiders are also referred to as tarantulas. In Australia the theraphosids are represented by the whistling spiders (Selenocosmia sp.). These ground-dwelling spiders are big enough to prey on small frogs and reptiles, but are not known to eat birds. They are also known as barking spiders.

Do we have tarantulas in Australia?

It depends on what you mean by the word "tarantula". Some people use it to describe the large hairy spiders of South and Central America. In Australia, the whistling spiders are also called Australian tarantulas, as they are related to the American spiders. However, the word tarantula is also used to refer to huntsman spiders.

Tarantula is derived from the name of a town in Italy, Taranto. This town is the original home of the wild dance called the tarentella. During the Middle Ages, the tarentella was thought to be the way to cure the bite of a particular spider. The symptoms - known as tarantism - included severe pain, swelling, spasms, nausea and vomiting, palpitations, and fainting, along with exhibitionism, melancholia and delirium. It was hard to determine whether an actual bite had occurred or if people were merely displaying some form of madness or hysteria. Scientists later determined that many cases might indeed have been the result of a bite, although much of the fierce dancing and extreme behaviour may reflect more about the social and sexual repression at the time.

The alleged spider that caused all of these symptoms was called a tarantula, but the species was incorrectly identified. The original spider identified by the people of the time was a wolf spider (Lycosa tarantula). However, it was subsequently shown to cause little serious results when it bit people. Finally, it was shown that the real culprit was a Black Widow relative, Latrodectus tredecimguttatus, known in Southern Europe as the "malmignatte". The symptoms of this spider's bite (and of other Latrodectus species, including the Redback Spider) match the whole-body symptoms experienced during tarantism.

Information from: Hillyard, P. 1994. The Book of the Spider. Hutchinson, London.

Do we have scorpions in Australia?

Yes we do. Scorpions are common in gardens and forests throughout eastern Australia and are found under logs, rocks and in shallow burrows in earth banks. They are nocturnal - which is why we rarely see them - but they can be disturbed during the day, especially during the prolonged wet weather. There are also species that live in the desert and others that inhabit tropical rainforests.

What is the world's most dangerous spider?

It is hard to define which spider in the world is the most dangerous to humans. Several spiders could qualify, depending on what you mean by dangerous. Do you mean the spider with the most toxic venom, measured by its effect on newborn mice or other mammals? Or do you mean the spider that has caused the death of the most people? Those that have the strongest venom may not be encountered by humans very often, or may even have trouble piercing human skin and so are not considered to be ⟚ngerous'. Data are usually only kept on bites from spiders that are potentially deadly or cause severe reactions and these data are not recorded consistently at a national or international level. Here, we will define dangerous as �ly'.

In summary, on current evidence the most dangerous spiders in the world are funnel-web spiders (Atrax and Hadronyche species), Redback Spiders and their relations (Latrodectus species), Banana Spiders (Phoneutria species) and Recluse Spiders (Loxosceles species). In Australia, only male Sydney Funnel Web Spiders and Redback Spiders have caused human deaths, but none have occurred since antivenoms were made available in 1981.

The Australian funnel-web spiders are among the deadliest spiders in the world in the effect their bites have on humans and our primate relations (although the bite has little effect on dogs and cats). There are many species of funnel-web spiders in Australia but only male Sydney Funnel-webs have caused human deaths. There have been only 13 deaths recorded from male Sydney Funnel-webs, but up to 30-40 people are bitten by funnel-web spiders each year. Mouse spiders may have venom that is as toxic as that of some funnel-webs, as some patients have had severe reactions to their bites, although no-one has been recorded as having died from the effects of a mouse spider bite. Antivenoms are available for both funnel-web and Redback Spider bites.

A group of spiders that is dangerous in many countries belongs to the genus Latrodectus in the Family Theridiidae. In Australia we have the Redback Spider (Latrodectus hasselti). In America, a common representative of this genus is the Black Widow (Latrodectus mactans). Antivenoms are available for both funnel-web and Redback Spider bites.

A deadly spider which comes from South America is the Banana Spider, Phoneutria species. In south-eastern Brazil between 1970 and 1980, more than 7,000 people were admitted to hospital with bites from this spider. An antivenom also exists for this species.

The Recluse or Fiddleback Spider is a deadly spider belonging to the genus Loxosceles. Recluse spiders are found in many parts of the world and have been introduced into Australia. The venom of this spider can cause severe skin necrosis (eating away of the flesh) and can be fatal although not many deaths have been recorded.

How many dangerous spider bites occur in Australia each year? Has anyone died from a bite recently?

There have been no deaths in Australia from a confirmed spider bite since 1979. An effective antivenom for Redback Spiders was introduced in 1956, and one for funnel-web spiders in 1980. These are the only two spiders that have caused deaths in Australia in the past.

A spider bite is not a notifiable medical emergency, so there are no Australia-wide statistics, but the following figures give an idea of the incidence of reported bites in recent years.

Approximately 2000 people are bitten each year by Redback Spiders

Funnel-web spider antivenom has been given to at least 100 patients since 1980. Antivenom is given only when signs of serious envenomation are observed. Many spider bites are ɻlank', which means that no venom has been injected.

During 2000 the New South Wales Poisons Information Centre received 4,200 calls about spiders. However not all of these would have involved actual bites. Many reported bites are not able to be identified as definitely being from a spider, and it is nearly impossible to work out what species has caused a bite without seeing a specimen of the spider responsible.

Figures are from: Sutherland, S K and Nolch, G (2000) Dangerous Australian Animals. Hyland House, Flemington, Vic. 201 pp. ISBN 86447 076 3

  • Poisons Information Centre
  • The Children's Hospital at Westmead
  • Locked Bag 4001
  • Westmead, NSW 2145
  • Emergency telephone: 131 126 (24 hours, within Australia only)
  • Administrative telephone: +61 2 9845 3111
  • Fax: +61 2 9845 3597

What spiders in Australia may cause ill effects if they bite you?

In Australia, bites from at least two kinds of spiders - wolf spiders and white-tailed spiders - in some cases cause skin necrosis (eating away of the flesh). However, neither spider has caused human deaths. There are also a number of others which are thought to cause the same problem, but research is still being done to find out exactly which species do so.

Bites from many Australian spiders can cause localised reactions, with symptoms such as swelling and local pain at the site of the bite, sweating, nausea and vomiting and headaches. All of these symptoms will vary in severity depending on the age of the victim, their health, and the amount of venom that the spider was able to inject. Have a look at our spider fact sheets to find out more about individual species.

Do white-tailed spiders cause the skin condition known as necrotising arachnidism?

There is an ongoing debate among toxicologists and spider biologists about the effects and dangers of white-tailed spider bites. Most of these bites appear to cause little or no effect beyond transient local pain. However a small number of cases do cause more extensive problems. Whether this is a result of the spiders' venom or to bacteria infecting the wound at or after the time of the bite has not yet been resolved. It is also possible that some people may react badly to white-tailed spider bite, possibly because of immune system susceptibility or a predisposing medical condition.

  • Meier, J. & White, J. (1995) Handbook of Clinical Toxicology. CRC Press, Florida USA.
  • Whitehouse, R. (ed.) (1991) Australia's Dangerous Creatures, Readers Digest Pty Ltd, Surry Hills NSW.
  • Sutherland, S. & Sutherland, J. (1999) Venomous Creatures of Australia, Oxford University Press, South Melbourne.
  • Isbister,G. & Greay,M. (2000). "Acute and recurrent skin ulceration after spider bite" Medical Journal of Australia 172, 20 March 2000, pp.303-304

How do I control white-tailed spiders around the house?

Beyond killing or removing all white-tailed spiders that you encounter, you can try a prey reduction strategy. White-tailed spiders like to feed on Black House Spiders (Badumna insignis) in particular, but will take other spiders too. This means that you should clean up obvious spiders around the house (outside and in). This involves removing spiders from around windows, walls and verandas (by web removal and/or direct pyrethrum spray). The condition of the roof cavity and the underfloor area (if raised) should also be investigated. (from Mike Gray, Arachnologist, Australian Museum)

What is the biggest spider in the world?

The biggest spider in the world is the Goliath Spider, Theraphosa leblondi. It lives in coastal rainforests in northern South America. Its body can grow to 9 cm in length (3.5 inches) and its leg span can be up to 28 cm (11 inches). (from: Carwardine, M. 1995. The Guinness Book of Animal Records. Guinness Publishing.)

What is the biggest spider in Australia?

Australia's biggest spiders belong to the same family as the Goliath Spider. They are the whistling spiders. The northern species Selenocosmia crassipes can grow to 6 cm in body length with a leg span of 16 cm.

What is a Daddy-long-legs?

�y-long-legs' is the common name for a particular group of spiders, but it is also used for a different group of arachnids - the harvestmen or opilionids. As a result, there is a lot of confusion about what people mean when they say �y-long-legs'.

The animal which most biologists call Daddy-long-legs, is a spider, Pholcus phalangioides, which belongs to the spider family Pholcidae, order Araneida, class Arachnida. It has two parts to the body, separated by a narrow waist. It has eight eyes and eight very long thin legs. Pholcids often live in webs in the corners of houses, sometimes in bathrooms. Daddy-long-legs spiders (or pholcids) kill their prey using venom injected through fangs. Digestion is external, with fluids being squirted onto the prey item and the resulting juices sucked up by the spider.

The other eight-legged invertebrates that are sometimes called Daddy-long-legs, are members of the order Opiliones or Opilionida in the class Arachnida. Another common name for these arachnids is 'harvestmen'. Unlike spiders, their bodies do not have a 'waist', they do not produce silk and they normally have only one pair of eyes. They do not have venom glands or fangs, although they may produce noxious defence secretions. Most harvestmen eat smaller invertebrates but some eat fungi or plant material and others feed on carcasses of dead mammals and birds. Digestion is internal and some solid food is taken in, which is uncharacteristic for arachnids. You usually do not find harvestmen inside houses.

Are Daddy-long-legs the most venomous spiders in the world?

There is no evidence in the scientific literature to suggest that Daddy-long-legs spiders are dangerously venomous. Daddy-long-legs have venom glands and fangs but their fangs are very small. The jaw bases are fused together, giving the fangs a narrow gape that would make attempts to bite through human skin ineffective.

However, Daddy-long-legs Spiders can kill and eat other spiders, including Redback Spiders whose venom can be fatal to humans. Perhaps this is the origin of the rumour that Daddy-long-legs are the most venomous spiders in the world. The argument is sometimes put that if they can kill a deadly spider they must be even more deadly themselves. However this is not correct. Behavioural and structural characteristics, such as silk wrapping of prey using their long legs, are very important in the Daddy-long-legs' ability to immobilise and kill Redbacks. Also, the effect of the Daddy-long-legs' venom on spider or insect prey has little bearing on its effect in humans.

What are banana spiders and where are they found?

Banana spider is the common name given to large (3 cm body length) active hunting spiders of the genus Phoneutria (Family: Ctenidae). These spiders live in Central and South American rainforests. They are often found in rubbish around human dwellings, as well as hiding in foliage such as banana leaves where they sometimes bite workers harvesting bananas. They have a reputation for being quite aggressive.

Other names for this spider include: Kammspinne, Bananenspinne, Wandering spider, and Aranha armadeira.

The venom of this spider is neurotoxic - acting on the nervous system - and causes little skin damage. Symptoms of a bite include immediate pain, cold sweat, salivation, priapism, cardiac perturbations and occasional death. Research suggests it is similar in action to a-latrotoxin, which is produced by spiders of the Family Latrodectidae, such as the Redback and Black Widow Spiders.

Another spider that seems to have been given the common name "banana spider" is actually a completely unrelated species of orb weaving spider from Florida. This is a good example of why it is more useful to use scientific names when you are trying to find information on different animals or plants.

How do I find out about spiders in New Zealand?

The following New Zealand arachnologist (spider biologist) has offered to respond to inquiries from people interested in New Zealand spiders:

Dr Phil Sirvid
Entomology Section
Museum of New Zealand Te Papa Tongarewa
PO Box 467
Wellington, New Zealand
ph: +644 381 7362
fax: +644 381 7310

There is a book on New Zealand spiders: Forster, Ray and Lyn. 1999. Spiders of New Zealand and Their Worldwide Kin. University of Otago Press, ISBN 1 877133 79 5

What about white-tailed spiders in New Zealand?

Dr Phil Sirvid has this to say about white-tailed spiders in New Zealand:

"We have two species of white-tails in New Zealand - Lampona cylindrata and Lampona murina. They are both very similar in appearance, and can really only be separated from one another by viewing them under a microscope and examining certain features that aren't apparent to the naked eye.

Both have been introduced from Australia.

L. murina has been in the North Island of New Zealand for [over] 100 years, and has also been introduced to the Kermadecs, Lord Howe Island and Norfolk Island. I wouldn't be surprised if it's in the Chatham Islands as well. In Australia, this species is recorded along the East Coast from northern Queensland down through New South Wales and Victoria.

L. cylindrata had only been found occasionally in the South Island until the 1980s. About this time it seemed to spread rapidly throughout the South Island's main urban centres, and is known to occur as far south as Dunedin. This species is found along the southern part of Australia from Western Australia, through South Australia, Victoria and Tasmania, as well as in New South Wales and Queensland."

How can I find out about spiders in North, South or Central America?

We do not have a scientist at the Australian Museum who is an expert on the spiders of the Americas. However you could look at some US spider web sites to see if they can help you. Or you could contact an American spider expert.

Spider biology facts

What is the function and origin of silk glands and spinnerets in spiders?

The development of spinnerets and silk represents a major evolutionary shift that has defined the biological and ecological uniqueness of spiders within the arachnids. Silk glands produce the silk that the spider uses for a variety of purposes. The spinnerets are the special organs that the spider uses to extract and manipulate the silk as is it is produced from the silk glands.

Spiders evolved from ancestors that had limbs on the abdomen, as did arthropods like crustaceans such as crayfish. In fact, one of their few living marine relatives, Limulus, the so-called 'king crabs', has retained abdominal limbs, which have been lost or greatly modified in terrestrial spiders and other arachnids. The spiders' spinnerets are almost certainly derived from these ancestral abdominal limbs. In the basal (lowest) segments of spiders' limbs are small excretory glands - the coxal glands - that secrete and excrete waste body fluids. It seems that the silk glands may represent highly modified excretory glands that now manufacture silk instead of waste products, just as the spinnerets represent highly modified limbs.

It is possible that an intermediate stage in this process could have been the production of a secretion that included pheromone (scent) chemicals put out by the spider as a primitive 'signal line' by which a spider could find its way back to its retreat burrow. This role was then taken over by the production of silk. The silk then became useful not only as a safety line, but also for prey capture, manufacturing egg sacs and a host of other activities.

[Modified from text by Dr Mike Gray - Principal Research Scientist (Spiders)]

Reference: Foelix, R.F.1996. Biology of Spiders. Oxford Thieme.

Why don't spiders get stuck to their webs like the insects that they catch?

If you look at an orb-weaving spider in its web, you'll notice that the body is held slightly clear of the web, especially when the spider is moving about. The spider has only minimal (but vital) body contact with its web via the claws and bristles at the tip of each leg. Compared to its prey, which crashes or blunders into the web, the spider has only a tiny portion of its surface area in contact with a very small amount of silk at any time. This is obviously an important factor when moving on a sticky web - the less contact the better.

Another important factor is that not all silk lines in a sticky web are sticky. For example, the central part of an orb web (where the spider sits) is made of dry silk, as are the spokes supporting the sticky spiral line, which the spider can use when moving around its web. It's only when the spider makes a quick, direct charge across the sticky spiral to capture prey that it may cause some disruption to the web - but it never gets stuck.

Spiders also spend a lot of time grooming their legs. The spider draws the ends of its legs through its jaws to clean them of debris, which may include silk fragments. This is a very important maintenance activity that contributes to efficient function of the claws and bristles. As well as cleaning them, some secretions from the mouthparts may help make the leg tips less susceptible to sticking.

Why don't orb weavers and other spiders fall off their webs?

Most web-building spiders have three claws on their tarsi (feet) - two combed main claws and a smooth central hook. The web silk is only grasped by the hook, and is pushed against serrated bristles, which snag the silk and hold it. When the hook is released by a special muscle, the elastic silk simply springs away from the hook.

Why can some spiders climb slippery surfaces such as glass or run across ceilings?

Many hunting spiders possess dense hair tufts called scopulae under the claws of their tarsi (feet). These scopulae allow many spiders to walk on smooth vertical surfaces, across ceilings and even window panes. Each individual scopula hair splits into thousands of tiny extensions known as end feet. These end feet increase the number of contact points of the tarsi with the surface, creating great adhesion. This is similar to the adhesion forces at work in vertebrates such as skinks and geckos, which can also walk on ceilings with ease. The scopulae can be erected or laid flat by hydraulic pressure through changes in the pressure of the hemolymph (blood supply).

Do spiders sleep?

It really depends on how you define 'sleep'. All animals have some sort of ɼircadian' rhythm - a daily activity/inactivity pattern. Some are active during the day - diurnal - others are active at night time - nocturnal/crepuscular. The periods of inactivity are characterised by withdrawal (to a shelter perhaps) and a drop in metabolic rate.

This applies to spiders as well, although no studies have been done to measure the period of time spent in such a state or at what times different species do it. It seems that spiders with good eyesight that rely on vision to capture prey may tend to be more active in daylight hours, whereas others that rely on snares/webs could be active at other times, but this is not necessarily the case for all species.

In cold climates, spiders 'overwinter', which means that they have a kind of hibernation period. Overwintering involves a drop in metabolic rate, where the spiders bring their legs into their body and remain huddled in a shelter during the coldest months of the year.

This ability to shut down for a long period of time indicates that they might be able to do it for shorter periods in their everyday cycle, which could be seen as a form of sleep or rest.

Information from: Foelix, R.F. 1996. Biology of Spiders. Oxford Thieme and the Arachnology section, Australian Museum.

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Dispersion

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Dispersion, in biology, the dissemination, or scattering, of organisms over periods within a given area or over the Earth.

The disciplines most intimately intertwined with the study of dispersion are systematics and evolution. Systematics is concerned with the relationships between organisms and includes the classification of life into ordered groups, providing the detailed information essential to all biology. The study of evolution grew from a combination of systematics and dispersion, or distribution, as both Charles Darwin and Alfred Russel Wallace, pioneers in evolutionary biology, attested and, in turn, an understanding of the process of natural selection has illuminated the reasons for changes in distribution in the history of the Earth.

A specific type of organism can establish one of three possible patterns of dispersion in a given area: a random pattern an aggregated pattern, in which organisms gather in clumps or a uniform pattern, with a roughly equal spacing of individuals. The type of pattern often results from the nature of the relationships within the population. Social animals, such as chimpanzees, tend to gather in groups, while territorial animals, such as birds, tend to assume uniform spacing. Close attention must be paid to the scale of study in order to get an accurate reading of these patterns. If a group of monkeys occupies three widely separated trees, their spacing will obviously be aggregate yet in each tree, their spacing may appear to be uniform.

Distribution can be affected by time of day, month, or year. The most common form of distributional change occurs among migratory animals, which may be plentiful in the summer months and virtually absent in the winter. The forces governing the dispersal of organisms are either vectorial (directed motion), that is, caused by wind, water, or some other environmental motion, or stochastic (random), as in the case of the change in seasons, which gives no indication of where the dispersing organisms may ultimately settle. Dispersion may also be affected by the interrelationship of species with one another or with nutrients. Competition between species that depend on the same food types often leads to the elimination of one species, just as the extent of plant life often determines the boundaries of a species’ territory.

The irregularities of most distribution patterns are simplified in the case of life forms dependent upon relatively restricted habitats, like that of intertidal mollusks, which have an almost linear distribution along rocky seacoasts. A few species, most notably humans and the animals dependent upon them, have a worldwide distribution.

Among both plants and animals, dispersal usually takes place at the time of reproduction. Dispersal is defined as the movement of individual organisms from their birthplace to other locations for breeding. When overcrowding forces individuals to range outside the area in which they were born to find a mate or food, new populations occasionally arise. Insects often display distinctive abilities in this regard. East African locusts have been found in two forms, a bright green variety, which is sluggish and solitary, and a highly mobile, group-oriented, dark-coloured form that swarms in enormous numbers, eating all plant material in its path. It has been found that if the young of the green variety are raised in large, constricted groups, they metamorphosize into the dark form at maturity. This is called phase polymorphism. As their numbers increase and the food supply thins, the locusts undergo developmental and behavioral changes to produce the widest dispersion pattern possible.

Occasionally, natural selection acts to limit the dispersal of a species. On high mountaintops and isolated islands, for example, the predominance of flightless birds and insects is notable.

Organisms are also spread by passive means, such as wind, water, and by other creatures. This method is hardly less effective than active dispersal spiders, mites, and insects have been collected by airplanes over the Pacific as much as 3,100 km (about 1,900 miles) from land. Plants regularly spread their seeds and spores by the action of the wind and water, often with morphological adaptations to increase their potential range, as in the case of milkweed seeds.

Seeds are also spread by animals, often as undigested matter in the excrement of birds or mammals, or by attaching to animals via an assortment of hooks, barbs, and sticky substances. Parasites regularly use either their hosts or other creatures as distribution mechanisms. The myxoma virus, a parasite in rabbits, is carried by mosquitoes, which may travel as far as 64 km (40 miles) before infecting another rabbit.

Mountains and oceans can be effective barriers to the dispersal of organisms, as can stretches of desert or other climatological extremes. Some organisms can cross these barriers birds can cross the English Channel, while bears cannot. In such cases, the paths of the more mobile animals are called filter routes.

Over geologic ages there have been many dramatic changes in climate that have affected distribution and even the survival of many life forms. Furthermore, the continents appear to have undergone large-scale displacements (see continental drift), separating many species and encouraging their independent development. But the greatest factor in the dispersal of organisms, at least during the past 10,000 years, has been human influence.

This article was most recently revised and updated by William L. Hosch, Associate Editor.


Giant Spider Species Discovered in Middle Eastern Sand Dunes

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Scientists have unearthed a completely new species of spider hiding in sand dunes on the Israel-Jordan border.

With a legspan that stretches 5.5 inches, the spider, called Cerbalus aravensis, is the biggest of its type in the Middle East. "It is rare to find a new species of spider -- at least around this part of the world -- which is so big," said biologist Uri Shanas of the University of Haifa-Oranim in Israel, who discovered the arachnid.

Most of Cerbalus aravensis's habits remain a mystery, but the researchers say it is nocturnal and most active during the blazing summer heat. The spider lives in an underground den, hidden by a door that swings upwards to welcome unsuspecting prey like lizards and insects. To make the camouflage door, the spider patches together bits of sand.

The researchers believe the spider uses a "sit-and-wait" hunting strategy, biding its time till prey approach, Shanas said.

Unfortunately, the spider’s habitat is under immediate threat, he said. The Israeli government recently approved mining operations in the region, which could wipe out the creature.

Images: 1) Yael Olek/University of Haifa. 2) Roy Talbi/University of Haifa


Why describing new species is exciting and important!

For many researchers describing a new species seems like a tedious task. The differences between species might not be obvious, and the language confusing and foreign. This fact became apparent to me when I first presented my work to the Ant Lab at the Museum of Biological Diversity (MBD). As I described subtle differences in morphology, a little spine here and the shape of a hair there, I could tell that I had lost my audience by the dulled looks on my lab mates faces. How could they not see the differences in these two species?

Fig. 1 – Trachymyrmex new species on the left and T. zeteki on the right

“Some key differentiating characters: The integument is granulose, spatulate bi-colored setae occur between the frontal carina, the scape extends past the occipital corners. This is compared to a weakly irrorate integument, simple bi-colored setae between the frontal carina, and the scape reaching the occipital corners.”

Fig. 2 – In case you are not familiar with the some terms used in describing ant species

Totally clear, right?

While the differences in characters that separate Trachymyrmex new speciesand T. zeteki, are exciting for me, it seems to bore people to death. After my presentation, I received very helpful constructive criticism from my lab group. They thought it was interesting but a lot of my presentation went over their heads. My advisor, Dr. Rachelle Adams (Assistant Professor in the Department of Evolution, Ecology and Organismal Biology), encouraged me to find a way to turn the jargon into something people can digest and appreciate. I am still working on that, and it is a challenge many researchers face.

Species descriptions are important and a necessary part of daily life

Hopefully your parents told you when you were younger, never eat mushrooms you find in the woods. Taxonomy helps us understand what kind of mushroom you found, if it is edible, or if it might seriously hurt you if you eat it. Mushrooms are a great example of why taxonomy is important. Scientists need to describe and name species so that others can learn which characteristics define a species. Then chemists can tell us which are toxic. This information communicated to the public can potentially save lives! Taxonomists donate representations of species in museums so that they can be compared by other scientists in the future. Aside from publishing their species description, they submit the specimen used to describe the new species, a voucher specimens, physical specimens that serve as a basis of study, as representatives of their work.

Fig. 2 – Photo courtesy of Plain Janell Photography

My Taxonomic Conundrum

While working on my species description, I reviewed all the literature that included T. zeteki. The 30 papers covered a number of areas such as fungus-growing ant genomes, mating systems, alarm pheromones, larvae development, and gut bacteria. Sadly, almost half of the papers do not mention depositing voucher specimens! Two articles deposited their DNA sequences as vouchers to a database for molecular data. Any research that uses DNA sequences has to submit DNA vouchers to that database without it your work cannot get published. However, they do not have any physical vouchers linked to their sequences! This lack of physical vouchers was quite a surprise to me. The time I spent as an intern at the MBD Triplehorn Insect Collection, my advisors and other mentors strongly advocated the deposition of vouchers. Without being able to link your DNA sequence to a correctly identified organism, that DNA voucher loses its value. You cannot quickly identify an organism from DNA. Using morphology is the easiest way to do so! It seems many researchers don’t recognize the importance of vouchering and most non-taxonomic journals do not demand it. Research published without vouchers lacks reproducibility, an essential component of the scientific method.

In my research project, I am cleaning up the mess left behind from nearly twenty-years’ worth of poor vouchering and misidentification. I’m not only describing a new species and key characters that differentiate two cryptic species, I am listing all of the papers that have been published in the past twenty years using the names Trachymyrmex zeteki and Trachymyrmexcf. zeteki. By linking the new species description to these articles scientists can move forward knowing the proper identification of these hard-to-identify fungus-growing ants.

The deposition of vouchers should be required for all publications, and is crucial for, past, present, and future research in biology. In my undergraduate research, I discovered there is a disconnect between research museums like the MBD and many scientists. While I am still struggling to turn the technical jargon into information that can be swallowed by non-experts, there are discussions to be had about the importance of taxonomy as a cornerstone in biology.

If you want to learn more about fungus-growing ants and the importance of university research collections, come see us at the MBD Open House April 22, 10am – 4pm.

About the Author: Cody R. Cardenas is a Senior Undergraduate student in Entomology working in the Adams Ant Lab.