Information

Why do some grasshoppers have a black exoskeleton?


What species of grasshoppers have black exoskeletons? Is there a scientific difference in species between field crickets and grasshoppers?


Field crickets are rather distinct from grasshoppers. Although both groups are in the Order Orthoptera, grasshoppers are insects of the suborder Caelifera and field crickets are in the family Gryllidae of the suborder Ensifera.

For a discussion on insect coloraiton, see here.

If you'd like a specific species ID, please provide more information as requested in the comments.

Generally, field crickets are black, red or brown in color.

However, some species of grasshoppers are likewise black:

  • For example: Romalea species such as R. microptera and dark nymphs and morphs of R. guttata

Finally, here is a simple checklist of some typical differences between grasshoppers and crickets.


That Night 46 Million Grasshoppers Went to Vegas

In a new study, ecologists document the impact that the world’s brightest city has on the insect population.

Back in the summer of 2019, when joking about omens of the apocalypse still seemed fresh and fun, an endless swarm of grasshoppers descended on the Las Vegas Strip.

These insects were not biters or crop killers. But for weeks, every evening after sunset, their flapping wings filled the Sky Beam shining up from the pyramid of the Luxor casino, and their dead exoskeletons littered the sidewalks. The news media speculated that the outbreak could be attributed to a wet winter that allowed more eggs to hatch, and to the city’s artificial lights, which lured in grasshoppers like moths to flame.

A new analysis substantiates the link to the city’s lights — with worrying implications for the grasshoppers. Elske Tielens, an insect ecologist at the University of Oklahoma, found that on July 26, 2019, the peak night of the invasion, some 46 million grasshoppers took wing and then clustered over the brightest parts of the city.

“It’s really hard to wrap your mind around that volume,” she said. “We’re getting more grasshoppers in the air on a single day than you get humans coming to Vegas to gamble across an entire year.”

Visitors, of course, already knew Las Vegas cranked up its wattage at night. But some of that glow escapes straight up into space, where satellites measure it as the brightest city on the planet by a wide margin. The rest of that light, overflowing up into the atmosphere, forms a glowing dome that the U.S. National Park Service recently measured from 200 miles away, at the Great Basin National Park in Nevada.

Insect ecologists, for their part, have spent years studying how individual lamps and nighttime traps can be a silent siren call for insects, tempting them to their deaths. But Dr. Tielens and her colleagues, inspired by coverage of the 2019 Vegas grasshopper invasion, saw an opportunity to hunt for a wider pattern. They found that the roving clouds of grasshoppers had also been visible in weather radar data. Then they overlaid those radar movement patterns with separate maps of the city’s vegetation and its nighttime lighting.

Their study, published Tuesday in Biology Letters, suggested a daily commute. Before dusk, the grasshoppers began spread out over a wide area, gathered near vegetation. But as daylight faded they took to the skies. Then they clustered up to dozens of miles away, traveling not just toward individual bright points, as previous research has documented, but toward the glowiest regions of the Vegas sky.

“This is a really exciting paper,” said Brett Seymoure, an ecologist at Washington University in St. Louis who didn’t participate in the research. “We really don’t have evidence until right now, with this paper, that the light dome is guiding insects.”

Insect ecologists were already worried that different insect populations were declining around the world, perhaps because of pesticide use, habitat loss, pollution, climate change and artificial light at night. Dr. Tielens’s study, she says, does not estimate how many grasshoppers died, or how the nightly trip into the heart of Vegas might influence the next generation of grasshoppers. But it does show that artificial lighting can influence insects on a regional scale, and that on July 26, 2019, the city’s shimmer summoned 30 metric tons of crunchy, airborne biomass that might otherwise have been spread out across a much larger ecosystem.

“It’s scary from an ecological perspective,” Dr. Seymoure said. “It’s also probably pretty terrifying for a lot of people in Las Vegas, to have all of these grasshoppers swarming around. Although I think that would be pretty cool to see.”


History of Consumption

European populations and European-derived populations in North America historically have placed taboos on entomophagous eating practices (the consumption of insects) and continue to do so. This is notwithstanding the repeated attempts by entomologists to make insects more appealing. One of the best-known attempts is Ronald Taylor's 1975 book Butterflies in My Stomach, and the accompanying recipe guide, Entertaining with Insects (1976).

Although entomophagous eating practices have ceased in Europe, insects were at one time frequently eaten throughout the continent. Rural inhabitants of Europe consumed Cockchafer grubs until the 1800s, and these grubs were an important source of protein in Ireland during the famine of 1688. The Greeks and Romans also held some insects in high esteem as a food source. Ancient Greeks considered grasshoppers a delicacy, and even Aristotle wrote of eating cicadas. He considered them tastiest just before the final instar (stage between two molts), but females laden with eggs were also considered to be very good. The Greeks and Romans also ate a large Melolonthid grub, possibly Lucanus cervus, which Pliny wrote was fattened before consumption.

For many other populations the consumption of insects has continued into the early twenty-first century, or not long before that time. In Mexico a well-known example of cuisine involving insects is ahauatle, a mixture of hemiptera eggs, that Francisco Hernandez first described in 1649. The eggs were also dried and used as a condiment in the preparation of a traditional Christmas Eve dish, revoltijo. In Colombia the giant queen ants of the genus Atta are considered a gastronomical delicacy. There the consumption of giant queen ants can be traced to precolonial times: Gonzalo Jimenez de Quesada, founder of the Colombian capital city Santa Fe de Bogot á , first described their use by local peoples in the highlands in 1555.

The consumption of a wide variety of insects has been reported among Amerindian groups in South American rain forests, and insects have probably been part of that region's diet for a very long time. The insects that appear to be consumed most commonly are ants of the genus Atta, palm grubs, and caterpillars of various sorts. The naturalist Alfred Wallace first described the consumption of Atta queen ants in 1854:

They are eaten alive the insect being held by the head as we hold a strawberry by its stalk, and the abdomen being bitten off, the body, wings and legs are thrown down to the floor, where they continue to crawl along apparently unaware of the loss of their posterior extremities.

Palm grubs, the large, fatty, legless larvae of wood-boring weevils (Rhynchophorus ) found in the pith of felled palm trees, are a highly esteemed food among Amerindians. Bancroft, writing in the eighteenth century, claimed that palm grubs were equally highly esteemed by Europeans in Surinam, particularly by the French.

In Africa the use of insects as food is quite widespread and probably has deep historical roots. The mopane worm (Gonimbrasia belina ), the so-called snack that crawls, is one of the best known edible caterpillars. Termites are also utilized as food, especially in the early rainy season when the reproductive forms swarm from the nest. At one time, termites were such an important addition to the diet that their mounds were often disputed as property. Locusts (grasshoppers that go into a swarming phase), in particular the desert locust (Schistocerca gregaria ), also play a large role in the diet of Africans. In African history the locusts were so popular that people actually welcomed the arrival of swarms.

In the Middle East the desert locust was also a major source of food historically. Perhaps the most well-known incident involving locust eating was John the Baptist's ordeal in the desert during which he survived on locusts (St. John's bread) and honey. By using locusts as food he was observing the decree of Moses, "These ye may eat the locust after his kind and the bald locust after his kind, and the cricket after his kind and the grasshopper after his kind" (Leviticus 9:22).

In Asia the consumption of insects as food was described from the Chung-Qiu dynasty (770 – 475 B.C.E.) and continues to the present day. The most commonly consumed food insects in that region are bee brood (larvae and pupae), beetles such as Dytiscid and Hydrophilid beetles, and the giant water beetle (Lethocerus indicus ), the larvae of weevils like Rhynchophorus, and locusts of the genera Oxya and Locusta. Perhaps the most well-known insect eaten in the region is the pupa of the silkworm Bombyx mori.

In Australia the black honey ant (Camponotus inflatus ) is a highly sought-after food of Aboriginal Australiansand is even considered a totem animal by some clans. It is similar to the honey ant found throughout North and Central America: a modified worker ant with an enlarged body the size of a grape that is full of nectar. Digging up these ants is still considered an important traditional practice and is still taught to children. Witchetty grubs were also an important food of Australian Aborigines. The name witchetty grub refers to any number of root-boring larvae and probably includes Cossid moth larvae (Xyleutes leuchomochla ), giant ghost moth larvae (Hepialidae ), and longicorn beetle larvae (Cerambycidae ). One of the most unique and well-documented examples of entomophagous eating habits in Australia was the annual feast of bugong moths (Agrotis infusa ), which occurred until the 1890s. These moths migrate from the plains to aestivate (the summer equivalent of hibernation) in the rock crevices of the Bugong Mountains. Aboriginal Australians from many different tribes traditionally gathered to feast on them. Evidence of these feasts has been carbon-dated as early as 1000 C.E.


Contents

Locusts are the swarming phase of certain species of short-horned grasshoppers in the family Acrididae. These insects are usually solitary, but under certain circumstances become more abundant and change their behaviour and habits, becoming gregarious. [6] [7] [8]

No taxonomic distinction is made between locust and grasshopper species the basis for the definition is whether a species forms swarms under intermittently suitable conditions. In English, the term "locust" is used for grasshopper species that change morphologically and behaviourally on crowding, forming swarms that develop from bands of immature stages called hoppers. The change is referred to in the technical literature as "density-dependent phenotypic plasticity".

These changes are examples of phase polyphenism they were first analysed and described by Boris Uvarov, who was instrumental in setting up the Anti-Locust Research Centre. [9] He made his discoveries during his studies of the migratory locust in Caucasus, whose solitary and gregarious phases had previously been thought to be separate species (Locusta migratoria and L. danica L.). He designated the two phases as solitaria and gregaria. [10] These are also referred to as statary and migratory morphs, though strictly speaking, their swarms are nomadic rather than migratory. Charles Valentine Riley and Norman Criddle were also involved in achieving the understanding and control of locusts. [11] [12]

Swarming behaviour is a response to overcrowding. Increased tactile stimulation of the hind legs causes an increase in levels of serotonin. [13] This causes the locust to change colour, eat much more, and breed much more easily. The transformation of the locust to the swarming form is induced by several contacts per minute over a four-hour period. [14] A large swarm can consist of billions of locusts spread out over an area of thousands of square kilometres, with a population of up to 80 million per square kilometre (200 million per square mile). [15] When desert locusts meet, their nervous systems release serotonin, which causes them to become mutually attracted, a prerequisite for swarming. [16] [17]

The initial bands of gregarious hoppers are known as "outbreaks", and when these join together into larger groups, the event is known as an "upsurge". Continuing agglomerations of upsurges on a regional level originating from a number of entirely separate breeding locations are known as "plagues". [18] During outbreaks and the early stages of upsurges, only part of the locust population becomes gregarious, with scattered bands of hoppers spread out over a large area. As time goes by, the insects become more cohesive and the bands become concentrated in a smaller area. In the desert locust plague in Africa, the Middle East, and Asia that lasted from 1966 to 1969, the number of locusts increased from two to 30 billion over two generations, but the area covered decreased from over 100,000 square kilometres (39,000 sq mi) to 5,000 square kilometres (1,900 sq mi). [19]

Solitary and gregarious phases Edit

One of the greatest differences between the solitary and gregarious phases is behavioural. The gregaria nymphs are attracted to each other, this being seen as early as the second instar. They soon form bands of many thousands of individuals. These groups behave like cohesive units and move across the landscape, mostly downhill, but making their way around barriers and merging with other bands. The attraction between the insects involves visual and olfactory cues. [20] The bands seem to navigate using the sun. They pause to feed at intervals before continuing on, and may cover tens of kilometres over a few weeks. [10]

Also, differences in morphology and development are seen. In the desert locust and the migratory locust, for example, the gregaria nymphs become darker with strongly contrasting yellow and black markings, they grow larger, and have a longer nymphal period the adults are larger with different body proportions, less sexual dimorphism, and higher metabolic rates they mature more rapidly and start reproducing earlier, but have lower levels of fecundity. [10]

The mutual attraction between individual insects continues into adulthood, and they continue to act as a cohesive group. Individuals that get detached from a swarm fly back into the mass. Others that get left behind after feeding take off to rejoin the swarm when it passes overhead. When individuals at the front of the swarm settle to feed, others fly past overhead and settle in their turn, the whole swarm acting like a rolling unit with an ever-changing leading edge. The locusts spend much time on the ground feeding and resting, moving on when the vegetation is exhausted. They may then fly a considerable distance before settling in a location where transitory rainfall has caused a green flush of new growth. [10]

Several species of grasshoppers swarm as locusts in different parts of the world, on all continents except Antarctica and North America: [21] [22] [23] [a] For example, the Australian plague locust (Chortoicetes terminifera) swarms across Australia. [21]

The desert locust (Schistocerca gregaria) is probably the best known species owing to its wide distribution (North Africa, Middle East, and Indian subcontinent) [21] and its ability to migrate over long distances. A major infestation covered much of western Africa in 2003-4, after unusually heavy rain set up favourable ecological conditions for swarming. The first outbreaks occurred in Mauritania, Mali, Niger, and Sudan in 2003. The rain allowed swarms to develop and move north to Morocco and Algeria, threatening croplands. [25] [26] Swarms crossed Africa, appearing in Egypt, Jordan and Israel, the first time in those countries for 50 years. [27] [28] The cost of handling the infestation was put at US$122 million, and the damage to crops at up to $2.5 billion. [29]

The migratory locust (Locusta migratoria), sometimes classified into up to 10 subspecies, swarms in Africa, Asia, Australia, and New Zealand, but has become rare in Europe. [30] In 2013, the Madagascan form of the migratory locust formed many swarms of over a billion insects, reaching "plague" status and covering about half the country by March 2013. [31] Species such as the Senegalese grasshopper (Oedaleus senegalensis) [32] and the African rice grasshopper (Hieroglyphus daganensis), both from the Sahel, often display locust-like behaviour and change morphologically on crowding. [32]

North America is currently the only continent besides Antarctica without a native locust species. The Rocky Mountain locust was formerly one of the most significant insect pests there, but it became extinct in 1902. In the 1930s, during the Dust Bowl, a second species of North American locust, the High Plains locust (Dissosteira longipennis) reached plague proportions in the American Midwest. Today, the High Plains locust is a rare species, leaving North America with no regularly swarming locusts.

Ancient times Edit

Study of literature shows how pervasive plagues of locusts were over the course of history. The insects arrived unexpectedly, often after a change of wind direction or weather, and the consequences were devastating. The Ancient Egyptians carved locusts on tombs in the period 2470 to 2220 BC. A devastating plague in Egypt is also mentioned in the Book of Exodus in the Bible. [19] [33] The Iliad mentions locusts taking to the wing to escape fire. [34] Plagues of locusts are also mentioned in the Quran. [15] In the ninth century BC, the Chinese authorities appointed anti-locust officers. [35]

Aristotle studied locusts and their breeding habits and Livy recorded a devastating plague in Capua in 203 BC. He mentioned human epidemics following locust plagues which he associated with the stench from the putrifying corpses the linking of human disease outbreaks to locust plagues was widespread. A pestilence in the northwestern provinces of China in 311 AD that killed 98% of the population locally was blamed on locusts, and may have been caused by an increase in numbers of rats (and their fleas) that devoured the locust carcasses. [35]

Recent times Edit

During the last two millennia, locust plagues continued to appear at irregular intervals with the main recorded outbreaks of the desert and migratory locusts occurring in Africa, the Middle East, and Europe. Other species of locusts caused havoc in North and South America, Asia, and Australasia 173 outbreaks over a period of 1924 years have been recorded in China. [35] The Bombay locust (Nomadacris succincta) was a major pest in India and southeastern Asia in the 18th and 19th centuries, but has seldom swarmed since the last plague in 1908. [36]

In the spring of 1747 locusts arrived outside Damascus eating the majority of the crops and vegetation of the surrounding countryside. One local barber, Ahmad al-Budayri, recalled the locusts "came like a black cloud. They covered everything: the trees and the crops. May God Almighty save us!" [37]

The extinction of the Rocky Mountain locust has been a source of puzzlement. It had swarmed throughout the west of the United States and parts of Canada in the 19th century. Albert's swarm of 1875 was estimated to cover 198,000 square miles (510,000 km 2 ) (greater than the area of California) and to weigh 27.5 million tons, with some 12.5 trillion insects. [38] The last specimen was seen alive in Canada in 1902. Recent research suggests the breeding grounds of this insect in the valleys of the Rocky Mountains came under sustained agricultural development during the large influx of gold miners, [39] destroying the underground eggs of the locust. [40] [41]

Monitoring Edit

Early intervention is a more successful means of dealing with locusts than later action when swarms have already built up. The technology to control locust populations is now available, but the organisational, financial, and political problems may be difficult to overcome. Monitoring is the key to reducing damage, with the early detection and eradication of bands being the objective. Ideally, a sufficient proportion of nomadic bands can be treated with insecticide before the swarming phase is reached. Reaching this objective may be possible in richer countries like Morocco and Saudi Arabia, but neighbouring poorer countries (Mauritania, Yemen, etc.) lack the resources and may act as a source of locust swarms that threaten the whole region. [15]

Several organisations around the world monitor the threat from locusts. They provide forecasts detailing regions likely to suffer from locust plagues in the near future. In Australia, this service is provided by the Australian Plague Locust Commission. [42] It has been very successful in dealing with developing outbreaks, but has the great advantage of having a defined area to monitor and defend without locust invasions from elsewhere. [43] In Central and Southern Africa, the service is provided by the International Locust Control Organization for Central and Southern Africa. [44] In West and Northwest Africa, the service is co-ordinated by the Food and Agriculture Organization's Commission for Controlling the Desert Locust in the Western Region, and executed by locust control agencies belonging to each country concerned. [45] The FAO also monitors the situation in the Caucasus and Central Asia, where over 25 million hectares of cultivated land are under threat. [46] In February 2020, in an effort to end massive locust outbreaks, India decided to use drones and special equipment to monitor locusts and spray insecticides. [47]

Control Edit

Historically, people could do little to protect their crops from being devastated by locusts, although eating the insects may have been some consolation. By the early 20th century, efforts were being made to disrupt the development of the insects by cultivating the soil where eggs were laid, collecting hoppers with catching machines, killing them with flamethrowers, trapping them in ditches, and crushing them with rollers and other mechanical methods. [19] By the 1950s, the organochloride dieldrin was found to be an extremely effective insecticide, but it was later banned from use in most countries because of its persistence in the environment and its bioaccumulation in the food chain. [19]

In years when locust control is needed, the hoppers are targeted early by applying water-based, contact pesticides using tractor-based sprayers. This is effective but slow and labour-intensive, and where possible, spraying concentrated insecticide solutions from aircraft over the insects or the vegetation on which they feed is preferable. [48] The use of ultralow-volume spraying of contact pesticides from aircraft in overlapping swathes is effective against nomadic bands and can be used to treat large areas of land swiftly. [43] Other modern technologies used for planning locust control include GPS, GIS tools, and satellite imagery, and computers provide rapid data management and analysis. [49] [50]

A biological pesticide to control locusts was tested across Africa by a multinational team in 1997. [52] Dried fungal spores of a Metarhizium acridum sprayed in breeding areas pierce the locust exoskeleton on germination and invade the body cavity, causing death. [53] The fungus is passed from insect to insect and persists in the area, making repeated treatments unnecessary. [54] This approach to locust control was used in Tanzania in 2009 to treat around 10,000 hectares in the Iku-Katavi National Park infested with adult locusts. The outbreak was contained and the elephants, hippopotamuses, and giraffes present in the area were unharmed. [44]

The ultimate goal in locust control is the use of preventive and proactive methods that disrupt the environment to the least possible extent. This would make agricultural production easier and more secure in the many regions where growing crops is of vital importance to the survival of the local people. [18]

As experimental models Edit

The locust is large and easy to breed and rear, and is used as an experimental model in research studies. It has been used in evolutionary biology research and to discover to what degree conclusions reached about other organisms, such as the fruit fly (Drosophila) and the housefly (Musca), are applicable to all insects. [55] [56] It is a suitable school laboratory animal because of its robustness and the ease with which it can be grown and handled. [57]

As food Edit

Locusts are edible insects. Several cultures throughout the world consume insects, and locusts are considered a delicacy and eaten in many African, Middle Eastern, and Asian countries. They have been used as food throughout history. [58]

They can be cooked in many ways, but are often fried, smoked, or dried. [59] The Bible records that John the Baptist ate locusts and wild honey (Greek: ἀκρίδες καὶ μέλι ἄγριον , romanized: akrides kai meli agrion) while living in the wilderness. [60] Attempts have been made to explain the locusts as some ascetic vegetarian food such as carob beans, but the plain meaning of akrides is the insects. [61] [62]

The Torah, although disallowing the use of most insects as food, permits the consumption of certain locusts specifically, the red, the yellow, the spotted grey, and the white are considered permissible. [63] [64] In Islamic jurisprudence, eating locusts is considered halal. [65] [64] The Islamic prophet, Muhammad, was reported to have eaten locusts during a military raid with his companions. [66]

Locusts are eaten in the Arabian Peninsula, including Saudi Arabia, [67] where consumption of locusts spiked around Ramadan especially in the Al-Qassim Region in 2014, since many Saudis believe they are healthy to eat. The Saudi Ministry of Health warned that pesticides they used against the locusts made them unsafe. [68] [69] Yemenis also consume locusts, and expressed discontent over governmental plans to use pesticides to control them. [70] ʻAbd al-Salâm Shabînî described a locust recipe from Morocco. [71] 19th century European travellers observed Arabs in Arabia, Egypt, and Morocco selling, cooking, and eating locusts. [72] They reported that in Egypt and Palestine locusts were consumed. [73] They reported that in Palestine, around the River Jordan, in Egypt, in Arabia, and in Morocco that Arabs ate locusts, while Syrian peasants did not eat locusts.

In the Haouran region, Fellahs who were in poverty and suffered from famine ate locusts after removing the guts and head, while locusts were swallowed whole by Bedouins. [74] Syrians, Copts, Greeks, Armenians, and other Christians and Arabs themselves reported that in Arabia locusts were eaten frequently and one Arab described to a European traveler the different types of locusts which were favored as food by Arabs. [75] [76] Persians use the Anti-Arab racial slur "Arabe malakh-khor" (Persian: عرب ملخ خور ‎, literally Arab locust eater) against Arabs. [77] [78] [79]

Locusts yield about five times more edible protein per unit of fodder than cattle, and produce lower levels of greenhouse gases in the process. [80] The feed conversion rate of orthopterans is 1.7 kg/kg, [81] while for beef it is typically about 10 kg/kg. [82] The protein content in fresh weight is between 13 and 28 g / 100 g for adult locust, 14–18 g / 100 g for larvae, as compared to 19–26 g / 100 g for beef. [83] [84] The calculated protein efficiency ratio is low, with 1.69 for locust protein compared to 2.5 for standard casein. [85] A serving of 100 g of desert locust provides 11.5 g of fat, 53.5% of which is unsaturated, and 286 mg of cholesterol. [85] Among the fatty acids, palmitoleic, oleic, and linolenic acids were found to be the most abundant. Varying amounts of potassium, sodium, phosphorus, calcium, magnesium, iron, and zinc were present. [85]


5 types of animals with exoskeletons

Arthropods are invertebrates that make up 75% of all animals on earth, and they are mostly insects. The phylum also includes spiders, centipedes, and crustaceans. This group, arthropods, makes up the majority of animals with exoskeletons. In addition to arthropods, there are some species of mollusks that have exoskeletons and sea sponges that secrete their exoskeletons.

Examples of animals with exoskeletons:

1. Insects

Insects are the largest group of arthropods on the planet. They have hard exoskeletons made out of chitin which protects and supports there bodies that are comprised of the head, thorax, and abdomen.

Cicada

Some species of cicada live underground for the first 2-17 years of their lives. Once out of the ground the cicada is called a nymph. The nymph quickly looks for a tree to aid in the shedding of its exoskeleton. Once they finish molting they can finally begin their adult lives, the exoskeleton stays behind attached to the tree.

Grasshopper

There are fossils of ancient grasshoppers that date back more than 300 million years, well before dinosaurs roamed the earth. Grasshoppers have large back legs for jumping but some species also have wings and are able to fly. Like other insects, grasshoppers have a hard exoskeleton made of chitin that protects their soft insides.

Ladybug

Ladybugs are one of the most recognized insects due to their bright red color with black dots. These colorful wing-covers protect their delicate wings that are about 4 times the size of their bodies. A ladybug’s exoskeleton is also made of chitin and protects its insides and holds its body together similar to the way our skeletal system holds us together.

2. Spiders & arachnids

Spiders are part of a group of animals called arachnids, which also belong to the group arthropods. Other types of arachnids include ticks, mites, chiggers, and scorpions whom like spiders, all have exoskeletons.

Black Widow

While they are rarely fatal to humans, black widow spiders and the most venomous spiders in North America. The female black widow is usually twice the size of a male and is known for actually eating the male. This is after they have successfully mated, hence the name “black widow”. Both the male and female of this species have hard exoskeletons made of protein and chitin.

Brown Recluse

Brown recluses get their name from the fact they are very reclusive and keep to themselves, human bites are rare as their fangs are small and cannot bit through clothing. These spiders are often mistaken for other non-venomous spiders like the wolf spider. A brown recluse can easily be identified by a violin-shaped marking on the top of its shell, or exoskeleton.

Emperor Scorpion

the emperor scorpion is another type of arachnid with a very tough outer-shell, or exoskeleton that it uses for protection from predators in the savannas of West Africa where it lives. They can grow up 7-8 inches in length and due to the fact they have mild venom and are fairly docile, they are big in the pet trade. While their stingers look pretty intimidating, they rely more on their massive claws to kill prey. An emperor scorpion sting has been compared to a bee sting for a human, not pleasant but not terribly painful considering the size of their stinger.

3. Crustaceans

Crustaceans are a group of arthropods with hard exoskeletons that mainly live in the ocean. However some are found in freshwater like the crayfish and others on land like the Coconut crab, the largest land dwelling arthropod on earth.

European Lobster

Lobsters have a very long life span and some species can live over 100 years, continuing to grow the whole time. During the first 5 to 7 years of life a lobster will molt its exoskeleton about 25 times. After that, an adult lobster will only molt about once every year or sometimes 2.

Coconut Crab

The coconut crab is a type of hermit crab that will actually scale coconut trees and use its massive flaws to crack them open and get to the meat inside. These crabs are not to be trifled with, their pincher can create a force of up to 740lbs of pressure… enough to snap off a human finger. Coconut crabs are known for eating their own exoskeleton after molting, which can take about a month.

Crayfish

Freshwater crayfish, commonly called crawdads around here, are kind of like mini-lobsters found in streams, rivers, creeks, and other fresh bodies of water. Like lobsters, they regularly have to molt their exoskeletons in order to grow. The exoskeleton itself does not grow with the crayfish, which is why they must molt. For a few days following a molt they are left with a much softer exoskeleton which makes them more vulnerable to predators.

4. Millipedes & centipedes

Both millipedes and centipedes are arthropods, and both have exoskeletons.

Millipedes vs centipedes – what’s the difference?

Many get these two species of arthropods confused, but they are actually quite different. All millipedes are non venomous while many types of centipedes are venomous with some even being deadly.

Depending on the species the actual number of legs that these creatures can have greatly varies, what always holds true though is the fact that millipedes have 2 sets of legs per body segment while centipedes only have one pair of legs per segment. With this in mind, millipedes usually end up having more legs than centipedes.

Millipedes

A millipede’s hard exoskeleton is it’s primary defense from predators and things that would like to make it into a meal. They are known for balling up in a coil to make themselves even less appetizing and further protect their more vulnerable underside. While millipedes are not venomous, some species may secrete a poison as a secondary defense against predators.

Centipedes

Like millipedes, centipedes have a hard exoskeleton. Centipedes use venom to kill all of their prey, but they typically avoid humans and don’t pose any threat to us. While their venom isn’t likely to be fatal to humans, species like the Asian Forest Centipede are highly venomous and if bitten can cause serious pain and swelling.

5. Shelled mollusks

The two types of shelled mollusks that have exoskeletons are gastropods and cephalopods. Gastropods include snails and cephalopods include clams and oysters. Both types of mollusks have hard outer shells for exoskeletons. Their shells act not only as protection from predators but their actual homes. The exoskeleton of a mollusk is made of mostly calcium, compared to the exoskeleton of an arthropod which is made of chitin.

Snails

Everything from common garden snails to giant sea snails have exoskeletons in the form of shells. Their shells typically act as their primary defense against predators as they are able to just go inside and close up, similar to the way some turtles can. Unlike crustaceans, a snail does not shed its shell nor can it crawl out of it. The shell grows along with the snail throughout its life.

Clams & oysters

Seashells are the old exoskeletons of clams, oysters, snails, and other sea creatures that live in shells. A clams exoskeleton is used much in the same way as the snails, to protect its tender insides from predators. Even though a clam or oyster’s insides may look like a pile of slime to us, they actually have a nervous system, a heart, a mouth, and a stomach.


Giant grasshoppers ravaging Central Florida

Alice McKinstry Davis, curator of the Eustis Historical Museum and Preservation Society, first saw the 4-inch creatures chowing down on a flower-garden smorgasbord outside the museum in downtown Eustis a few weeks ago.

"We didn't know what to think," Davis said. "I'd never seen anything like them. They were devouring all our broadleaf plants."

Davis ran for the bug spray. The king-sized grasshoppers just sneered. Alarmed, she called experts for help.

"About all you can do is hit 'em with a 2-by-4," said Pris Peterson, master gardener at the Lake County Agricultural Center.

So Davis went out and rounded up some enthusiastic high-school volunteers willing to stomp on the critters. Between the teens and a direct application of an unusually potent insecticide, museum workers beat back the infestation.

Davis had made the acquaintance of an Eastern lubber, which is to grasshoppers what King Kong was to apes. Yellow with red and black markings, it's the only one of the 70 species of grasshoppers that live in Florida that defies natural predators and insecticides.

It's a nasty pest. Too fat to fly, lubbers can jump high and long. When disturbed, they spread their wings and hiss. Try to touch one, and it's likely to eject a foul-smelling, irritating foam intended to keep you away. It's highly effective.

Agricultural officials and bug specialists from the University of Florida say no back yard in Central Florida is immune to a lubber infestation this year.

Usually the population of Eastern lubbers is held back by lack of food or water, parasites and insect diseases. But the combination of a dry winter with a return to normal rainfall this summer may be responsible for a bumper crop in Central Florida, said John Capinera, a professor and chairman ofUF's Department of Entomology.

"Lubbers seem to like a wet environment," Capinera said.

Capinera said he has been getting a rising number of inquiries about the bad boys of the insect world. But even though grasshoppers are the most abundant insect above ground, little is known about them.

Scientists have learned that most grasshoppers are important in returning nutrients stored in plants back into the soil and as a food source for birds, reptiles, skunks, foxes and mice.

Nothing finds lubbers tasty, however. Biologists think they are poison to birds, said Capinera, author of Grasshoppers of Florida, a field guide published last year.

Lubbers favor shrubs, herbs, broadleaf plants and grasses -- in other words, almost every plant on the farm or in the garden. If their numbers get out of control, they can cause significant crop damage.

So far, however, they've just been startling homeowners unaccustomed to seeing grasshoppers that look as if they'd have a starring role in a horror flick. After all, they have five eyes, viselike jaws and ever-moving mouth parts. The best way to control the lubbers is to hope that something gets them when they're young -- they're not so toxic then, and birds sometimes eat them.

"But when they get older, they are too big and crunchy to be appetizing," said Linda Landrum, an urban horticulturist with the Volusia County Cooperative Extension Service.

Need to get them out of your back yard? You might try offering some to a local school -- they're commonly used for dissection in biology courses because of their size.

Other than that, you could try Landrum's favorite disposal method: Grab the squirmy hoppers and drown them in a bucket of soapy water.

Be advised, however, that catching and holding them down can be stinky, tricky and often gross. The lubbers tend to resist the procedure.


Here’s Some Advice On Eating Cicadas From A Top Nutritionist

Fried cicadas are rolled into a sushi roll by Chef Bun Lai at Fort Totten Park in Washington, DC on . [+] May 23, 2021. (Photo by ANDREW CABALLERO-REYNOLDS / AFP) (Photo by ANDREW CABALLERO-REYNOLDS/AFP via Getty Images)

You may have heard that the trillions of cicadas emerging from beneath the ground this year as part of Brood X are edible.

If you’re interested in the idea of eating them but aren’t sure where to start, we have you covered with cicada-consuming advice from Jessica Fanzo, the director of Johns Hopkins’ Global Food Ethics and Policy Program. Fanzo has tried the cicadas herself and she says they are both nutritious and delicious.

Ew. Why should anyone consider eating cicadas?

Fanzo, who holds a Ph.D. in nutrition, said the trillions of cicadas emerging this year could be a good source of alternate, sustainable protein.

Although no one has done a nutritional composition of the cicadas, the nutritional composition is probably similar to other insects which are low in calories but high in protein and iron, said Fanzo. She said insects are more sustainable than larger animals like cows or pork.

If that’s true, why don’t more people eat bugs?

Insects might not be plentiful on menus in the United States, but they are a common part of many cultures’ cuisines, said Fanzo. She said there has been an increase in the popularity of insect powder that is mixed into protein powder or baked into chips in the US.

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“What you see less of is people eating whole insects,” she said.

What do the cicadas taste like?

They have a unique flavor that can vary depending on location, said Fanzo. She said she thinks they are buttery with a nutty flavor.

“They're good, they're really good,” she said.

Okay. What should I do if I want to try eating cicadas?

Start by finding them when they are still soft and grub-like, before they have fully developed their exoskeleton, said Fanzo.

Douglas Pfeiffer, an entomologist at Virginia Tech, said it only takes a few hours for cicadas to start to “harden up” after they emerge in their callow state. He advised picking them off tree trunks early in the morning.

Fanzo said she collected the soft-shelled cicadas in a ziplock bag and then put them in her freezer to kill them humanely. After they were dead, she boiled them for a few minutes to clean them off.

How you cook them after they are dead and cleaned is up to you. If you roast them with oil and salt they taste like a crunchy nut, Fanzo said. She has also fried them in a pan with sesame oil.

“They're kind of like little shrimp once you get over the ‘what am I eating factor,’” she said.

How long do I have to try the cicadas?

Cicadas should keep coming out until early June, according to University of Maryland entomology Michael Raupp.

If you decide you want to eat cicadas for more than another week or two, you can collect extra and freeze them, said Fanzo.

Will eating cicadas hurt the survival of the species overall?

Scientists say it is doubtful.

“I think it would take a real concerted effort to reduce the population,” said Pfeiffer. “The evolutionary approach that periodical cicadas use to minimize the impact of predation is predator satiation. But coming out all at once, predators are overwhelmed and can't put a dent in their population. You could collect a lot without reducing the general population.”

He said some smaller cicada broods appear to have gone extinct, but not necessarily because they were eaten. There were originally about 30 broods, but now there are 15. A potential threat to cicadas comes from increasing urbanization, which might leave them with less habitat and less tree roots from which to feed.

Raupp also said he doesn’t think enough humans will eat the cicadas to make an impact on their population.


Grasshopper spit

The seasonal approach of the days of summer means hot nights, baseball games, family vacations, pool parties, and lots of insects. Summer is insect time for sure! These cold-blooded organisms have to &ldquomake hay when the sun shines&rdquo in order to complete their life cycles before temperatures decline for the year.

Grasshoppers are insects that we don&rsquot often see until the good ol&rsquo summertime. That is because grasshoppers spend the winter in egg masses in the soil. Those eggs hatch in late spring, and the young hoppers are small and inconspicuous for weeks.

But as grasshoppers mature into adult stages, they grow in size and develop wings. Adult grasshoppers not only jump, but also fly, and that means these insects become more visible to casual observers. That is especially true in grassy habitats where they are often found &ndash after all, these insects are called grasshoppers for good reason!

Grasshoppers are not the favorite insects of most people. Butterflies they are not. That is probably the reason why, in the original storyboards produced 75 years ago for the Disney cartoon movie &ldquoBambi,&rdquo a grasshopper didn&rsquot appear in the final product. Here&rsquos the story. The unnamed grasshopper that was created to represent the smaller creatures of the forest was very grumpy and ornery. Ultimately, an engaging little bunny named Thumper filled that small-creature role. I&rsquom not surprised. Most humans prefer fuzzy, warm animals to coldblooded exoskeleton-encased insects. The grumpy grasshopper got booted and Thumper became a star!

Even though grasshoppers can be pests to farmers and gardeners, these jumpers in the grass have always held a fascination for young children who happen to encounter them. The grasshoppers jump or fly short distances to escape potential predators such as kids of the human sort. When that happens, the chase is often on.

Kids sometimes actually catch grasshoppers for an up-close look. And that is where the real action begins. First, the grasshopper kicks with those powerful jumping legs, using the spines of the back legs to gouge skin. If that doesn&rsquot let the grasshopper escape, it resorts to another trick: defensive regurgitation.

Defensive regurgitation has long been recognized as something that many grasshoppers and katydids practice. A few species of birds are also known to engage in a behavior that most people consider a disgusting activity. For instance, the subarctic seabird called the northern fulmar vomits a bright orange substance called stomach oil. Here in North America, nestlings of turkey vultures will projectile vomit when you approach their nest. Considering that the parents of these young turkey vultures feed their kids on regurgitated food from their craw &ndash with that food being flesh from carrion they have consumed &ndash you can imagine that it is not the best smelling-stuff in the world. I know based on practical experience, because I accidentally encountered a turkey vulture nest in an abandoned barn some years ago!

Growing up, I called the fluid produced in the mouths of grasshoppers &ldquotobacco juice.&rdquo Exactly why the material came to sometimes be called tobacco juice is not known. However, it does resemble, in color and consistency, the spit produced by people who chew tobacco. Some say the term might have originated because of the fact that grasshoppers sometimes feed on tobacco plants.

Entomologists have long assumed that the tobacco juice of grasshoppers was a type of defensive regurgitate. That conclusion is supported by the observation that the fluid is expelled when the insect is in some physical danger. However, there has not been a lot of research done on the subject. A recent study showed that apparently, the regurgitate might ward off smaller predators such as ants, but larger predators were not affected.

The grasshopper tobacco juice is a combination of partially-digested plant material and digestive enzymes. This much I know: if you catch a grasshopper or katydid and hold it, the insect will produce the fluid out of its mouth. If you get the fluid on you, it will stain your skin and be difficult to wash off. And oh, by the way, the grasshopper spit does taste bad. If you don&rsquot believe me, the next time you get some grasshopper tobacco juice on your hand, taste it. Friends, that is what scientists call research!


Video: Amazing Cicada Life Cycle

About the Cicada

Cicadas have a more robust appearance than grasshoppers, with a shorter, wider body. Like I mentioned earlier, many different varieties of cicadas exist, each of them distinct in their coloring: the Magicicada, or the 17-year cicadas that made news in 2013, are characterized by their black bodies, red eyes, and wing veins, while dog day cicadas are known for their light green coloring and clear wings.

In all varieties of cicada, however, the wings always extend noticeably past their bodies.

Cicadas do not swarm and pose much less of a threat to vegetation, especially crops, than locusts do. However, they can create damage to several cultivated crops, shrubs, and trees, since females lay their eggs in branches and twigs.

Cicadas, both in their nymph and their adult state, feed on tree sap through a long proboscis. They do not bite or sting for defense, but if you let a cicada rest on you for too long, it may think your body is a tree and try to feed on you.

Male cicadas sing to attract mates, for which they have three different courtship songs. The songs are specific to their species. They also have several other calls, including alarm calls. Cicadas are known for their loud songs, which can reach such high decibels that their songs are even capable of damaging human ears.

Unlike the locust, cicadas produce their sound by contracting their abdomen, which has tymbals on both sides. The male is the primary producer of sound, and its almost hollow abdomen acts as a sound box, amplifying their call.

Cicadas have a fascinating and complex reproduction system compared to locusts. After mating, females make a slit in a twig with her ovipostor. This is where she will lay her eggs. Once they hatch, the nymphs drop and bury themselves underground, feeding on deciduous tree roots while maturing.

The amount of time they take to mature depends on the particular variety. Magicicadas remain in nymph state for 13 to 17 years. Dog day cicadas are more common in the United States, and they take two to five years to mature into an adult. As an adult, they only live for several months, enough time to mate and start the life cycle again.


Why do some insects have hemoglobin while others have hemocyanin?

One aspect would be temperature and oxygen availability, since hemocyanin is generally more effective than hemoglobin in cold and oxygen-starved conditions.

I also believe hemoglobin has greater/wider affinity for competitive inhibitors, ie. other ligands that can bind instead of oxygen. Sometimes that's desirable, other times it's undesirable (CO, cyanide, or sulfides interfering with oxygen transport). That could play a role as well.

This could be a clue in relation to the geological record of oxygen abundance in the atmosphere. Arthropods evolved and were the top fauna in Cambrian to Silurian periods, when oxygen abundances were low. It wasn't until plants spread to the land in Silurian and Devonian time that oxygen abundances became more like they are today and in fact during the Carboniferous that were almost double today's levels, when insect sizes were huge.


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