<h1 class="ql-align-justify" > a means of escaping</h1>
For insects, the best means of self-defense is to quickly escape, run fast, or fly fast.
cockroach
Cockroaches, whose tails have fur that feels mechanical stimuli, are sensitive to changes in air pressure caused by fast-moving objects. Nerve impulses emanating from these fur receptors reach the thoracic nerve center through giant neurons at an acceleration of 3 meters per second, triggering an evasion response of cockroaches with a response time of no more than 50 milliseconds. housefly
housefly
The reaction speed is comparable to that of cockroaches, and after sensing the danger, it can quickly take off in 30 to 50 milliseconds, and then slip away.
Tiger moth
Ultrasonic echolocation waves emitted by bats can be perceived. If the ultrasonic intensity emitted by the bat is not high, the tiger moth will turn around and fly away; if the ultrasonic intensity increases to a certain limit, the tiger moth will quickly spiral and fall from the air. The alert response of other insects, while not as effective as tiger moths, is also very effective:
Madagascar cockroaches
Malagasy cockroaches "hiss, hiss" when disturbed; green bees
Green bees
When it feels danger, it will roll into a hard ball; the turtle beetle has a sticky meat pad at the ankle bone, which can attach its body tightly to the leaves or branches when it encounters danger... There are also many insects that play the game of pretending to be dead, and suddenly fall to the ground to pretend to be dead.
Tortoise beetles
The hard shell of insects is an effective means of defending against predators. The exoskeletons of most diving beetles are shiny and slippery, and at the same time very hard, they can often slip away even when held tightly in the palm of their hands.
The long spines, manes and fur of insects are also effective defensive weapons. It's not a pleasant thing for a carnivore to eat a mouthful of hair if you're not careful, and next time it might have to warn itself, "Don't touch that thing again!" As a result, many caterpillars weave their fur into cocoons as an adjunct to defend themselves against predator attacks.
Many insects have fracture lines on their appendages, and once caught by predators, they quickly break one of their legs and create a "golden cicada shell". This phenomenon is called "self-mutilation". This phenomenon is seen in blind spiders,
Blind spider
stick insect
stick insect
grasshopper
It is common with other long-legged insects. In general, the damage caused by this self-mutilation behavior is not serious, and many insects have regenerative abilities, such as the stick insect after several molts, can re-grow some or even the entire missing appendage.
<h1 class="ql-align-justify" > a chemical weapon with a hidden killer</h1>
In order to escape in time, many insects are also equipped with chemical weapons against predators.
Some insects can make toxins on their own, while others can obtain toxins through host plants and hide them in lymph or body tissues, seeping the toxins through the glands to the surface of the body when threatened or disturbed, and then suddenly spilling into the air, or spraying violently directly at the attacker.
Defensive chemicals can generally produce the following effects:
Rejection: A foul odor or poor taste is enough for a predator to remember for a lifetime. Take Tsubaki elephant as an example,
Tsubaki elephant
It has a specialized exocrine gland at the thoracic or abdominal location that secretes a hydrocarbon with a foul odor. These chemical components usually accumulate in a small sac next to the gland and are released to the surface of the body when needed. Some butterfly larvae have flip glands called Y glands under their heads, and when disturbed, they suddenly jump up and flip the Y glands at the attacker, releasing a strongly volatile liquid while moving their bodies back and forth to deter the offender.
In the dense forests of Tanzania inhabits a butterfly called Krippa, which has a substance called cardiac glycosides on its wings, derived from the leaves of a plant. Since these leaves are the favorite food of butterfly larvae, over time, cardiac glycosides will accumulate on the wings of butterflies. Although cardiac glycosides are not highly toxic substances, they do not taste good, and birds tend to treat them as poisonous butterflies after pecking at them.
Chemical Attacks: Irritating chemicals often force predators to stop attacking, while prey escapes when they clear the chemicals. Some cantharidins can produce cantharidin,
cantharis
It is a strongly irritating foaming agent that is usually stored in the lymph of cantharids. When threatened, blood trickles from the legs of the cantharid, and a strong pungent odor often deters predators. Certain insects, such as termites, cockroaches and stick insects, can produce irritating splashes, the most representative of which is the fart beetle. The insect's glands contain a precursor to an explosive compound that, when threatened, mixes together to form an extremely hot chemical— benzoquinone and water vapor — and then sprays them at the predator.
Adhesions: Certain sticky chemicals like glue can render predators incapacitated. When attacked by worker ants, cockroaches secrete a slimy liquid that sticks the attacker and renders it incapacitated. The head of the termite looks like a nozzle,
termite
It is born with defensive glands that can shoot viscous chemical fluids at intruders. These chemicals are extremely sticky and irritating, effectively blocking attacks by carnivorous arthropods such as ants, spiders, and centipedes.
Causes pain: Saddleback thorn moth caterpillar larvae, silkworm moth larvae, and other coleopteran larvae have hollow body hair that contains irritating substances that can cause pain sensations, and just rubbing these stings on the attacker will cause the stinging hairs to break, and the substance inside will run to the attacker's skin and produce a strong burning sensation, which can last for several hours. Many ants, bees and wasps can release venom — a mixture of proteins and amino acids — to their predators through intimidating stings that can cause pain but also allergic reactions.
Monarch butterflies living in North America are rarely attacked by birds during their long migrations.
Monarch butterfly
Why? Entomologists have found through dissection that birds are reluctant to eat these insects because they are full of toxins. The butterfly lays its eggs on a plant that contains a toxin, and after the larvae hatch, feed on this food, over time, and the toxin accumulates in the body. If a bird accidentally eats this butterfly, it will cause severe vomiting.
<h1 class="ql-align-justify" > a fake real protective color</h1>
Biologists believe that there must be an intrinsic reason why insects produce brilliant colors and patterns. Obviously, these colors and patterns have at least some defensive effect, providing a certain degree of protection for insects, so they are called "protective colors". Protective colors can be summarized into the following four categories:
Concealment: Insects that can skillfully integrate with their surroundings can often avoid the sight of predators. This defense, called "concealed color", can not only be mixed with the background color, but also blur the contour line of the body, eliminate the reflective bright spots generated by the smooth body surface, and avoid the leakage of position points.
Many groundhoppers and weavers
Textile Lady
They are covered with gray and brown spots, which allow them to subtly blend in with the dead leaves or gravel around them. Certain grass dragonflies
Grass dragonflies
Moss and lichen are attached to the back to increase camouflage. Tarantula
Tarantula
It is usually rare to see it hidden in the cave, but when it walks out of the cave, you will find that the protective color on its body looks like sand.
Mimesis: Some insects hide themselves by simulating surrounding objects, not only because their body color is very similar to their surroundings, but also because their morphology is very similar. This imitation of natural objects is called "mimicry." The stingrays that grow in Brazil usually inhabit thorny trees, like a spike growing on a tree. Horned cicadas sustain their lives by sucking sap from trees,
Horned cicadas
It's also cleverly hidden in the trees—at first glance it looks a lot like a thorn in a branch. The Indian wood tick is a master of simulation, its body is flat, veined, and it will swing back and forth with the wind, looking like a leaf blown by the wind. The stick insect is large, with a length of nearly 30 cm, and can reach 40 cm with legs. If it stops on a branch and does not move, it is almost exactly the same as a dead branch. Dead leaf butterfly that lives in the forests of southeastern Asia
Dead leaf butterfly
It looks like a dead leaf. Its wings are coloured on both sides, with a bright front, a blue-and-black background, dotted with small white spots, and the edges are inlaid with yellow-brown ripples and stripes. The main color on the back is brown, with dark stripes running through it, like veins on dead yellow leaves. Mulberry inchworms inhabit mulberry trees and often spit out filaments hanging from branches. Not only is the body color very similar to the color of the branches, but even the shape is almost exactly the same.
Pine moth larvae
Hidden in a pine tree, he has dark green stripes on his back that look very much like pine needles. The nocturnal moth inhabits the bark of birch trees, and its black and white body color is very similar to birch bark, which plays a good stealth role. The mottled, rough stink beetle on its back hides in the trunk and looks like a small piece of bark.
Imitation: A distinctive visual appearance can protect some insects from predators, while others will evolve a similar appearance to deter predators. This is actually a tactic of confusion. For example, some butterflies are not inherently poisonous, but look very similar to poisonous butterflies.
Some butterflies have round spots on their hindwings, which look very much like the eyes of ferocious animals, which they use to intimidate carnivores. The Caligari butterfly that lives in South America,
Cary Butterfly
On its hindwings there is a pattern that is very similar to an owl, and when they encounter birds, they will turn their hind wings upwards, and the birds will most likely be deceived. There is a moth that specifically imitates a wasp, does not have a scale film on its wings, is as transparent as a wasp, and has the same body color as a wasp. The most peculiar thing is that they also have long sting-like appendages on their abdomen, and they also make bending movements from time to time. They even fly in a manner like wasps.
The velvet wasp larvae have heads that look like snake heads, enough to mess with the real thing. Japanese camphor silkworm moth
Japanese camphor silkworm moth
The pattern on the wings resembles the face of a large-billed frog, and the two round "big eyes" look very scary. The camphor silkworm moth dwells in the grass during the day, and if a bird passes by, it will suddenly fly, like a frog that suddenly jumps out of the grass.
Warning color: Many insects that take active defensive measures have bright colors or contrasting patterns, and predators often associate these colors or patterns with unpleasant feelings, and an unpleasant experience can often make the predator remember for a lifetime, and never want to touch the prey that is not in sight. A few insects may fall prey, but the population as a whole will benefit. Many moths and butterflies contain toxins in their bodies, and their appearance is usually very bright, which can play a clear warning role, as if to declare to the enemy, "I am poisonous, do not eat me!" ”
The birch butterfly, which lives in Africa, has an orange color throughout.
Birch butterfly
There are obvious black and white spots, which are very conspicuous in the sun, and birds will actively retreat after seeing it, because the insect has a toxin that can cause heart failure. The ladybug is dotted with black spots or beautiful patterns, which is very conspicuous, but few enemies attack it, and it turns out that the ladybug's leg joints can secrete a foul-smelling odor. Its beautiful appearance seemed to warn its predators: "I stink, don't touch me." ”