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Grasshoppers and larvae eat insect eggs (C is poisonous eggs to be eaten)
Eggs are a delicacy for humans or any other mammal, and chickens have not evolved a strategy to make eggs poisonous to withstand the consumption of "bad human uncles". Eggs seem helpless, but for insects, protecting eggs and eggs is a major life event that must be considered to ensure life reproduction. Bugs have their own tricks.
Thomas Eisner, the father of chemical ecology, published an interesting PNAS article in 1999 deciphering how eggs defend against predators. Thomas was a chemist in the early days, and later he was very interested in biology, so he combined chemistry with ecology and animal behavior to create chemical ecology. The story is very interesting, it is said that Thomas went on an academic sabbatical, observed it, and then he studied it and published it. Let's elaborate on the mystery of this.
The grasshopper (Ceraeochrysa cubana) is a neat and elegant bug, but its son, the aphid, is a completely sloppy ghost. Aphids usually carry a small handful of garbage and hide themselves in the garbage when they encounter danger. Especially for its rival small ants, the aphid's garbage life model is very effective. The unkempt insect naturally has its ferocity. The aphid is a very ferocious insect with a large set of teeth that pierces the egg shell of the lamp moth (Utetheisa ornatrix) and sucks the eggs. You should know that although the aphid is small, for the eggs, the big fangs of the aphid are simply a heavy puncture tank.
<h3>So how do eggs protect themselves? </h3>
The study found that the eggs of the lamp moth did not protect themselves by thickening the thickness of the eggshell, but cleverly used chemical weapons. Through the test, the eggs actually contained "toxic substances" alkaloids. There are many types of alkaloids, such as betel nut, poppy, tobacco, coffee, tea contain alkaloids. Alkaloids are mostly alkaline ring-like structures containing N, with a bitter or other taste, and are very unpleasant to eat (except for people).
The larvae of the lamp moth feed on the beans of the legume family Crotalariamu cronata. Female moths lay their eggs on top of pig poop bean leaves, laying eggs together at a time, ranging from more than ten or twenty or thirty. The eggs of the lamp moth are a favorite delicacy of grasshopper larvae, just as humans like to eat eggs. (Here we have to be glad that chickens have not evolved this strategy, otherwise we would not be able to eat eggs) However, the alkaloid content in the eggs of the lamp moth is variable, some are there, some are not, sometimes a little more, sometimes a little less. The alkaloid content in the eggs, like the daughter's dowry, depends entirely on how much money the mother "suffered" before she died, and how much money was saved (alkaloids). Therefore, when the aphids eat, they will choose those delicious eggs instead of poisonous eggs.
Thomas caught some aphids first and starved them for two days. When a hungry aphid can now eat 30-40 eggs, give it 20 eggs and see how the aphids choose. When an aphid encounters a group of eggs, it must be excited, usually rushing up to bite one or two to taste it, and if the taste is not good, it will give up a whole nest of eggs and find another egg. The alkaloids in the eggs of the lamp moth can be a good protection against the damage of aphids.
Pig poop beans, beans are rich in alkaloids. If the insect does not get enough when it is young, it will be the life of a single dog when it grows up
How important are alkaloids? For example, it's like a Shanghainese marriage room. Lamp moth larvae accumulate alkaloid toxins in beans by feeding on pig droppings. The accumulation of alkaloids in the body can not only avoid the hunting spiders to prey on caterpillars; and after the caterpillar feathers, the light moths with a lot of alkaloids in the body, even if they hit the spider web at night, the spider with the web will immediately recognize the poison and let it go. The most important thing is that when the female lamp moth is courting, she will evaluate whether to mate with the male lamp moth according to the ability of the male lamp moth to "practice poison" and the amount of alkaloids in the body. If it is a non-toxic person, it can only be a single dog. If it is a male moth rich in toxins, it is not only favored by the female, but also takes the toxin as a gift when mating, and passes it to the female through the "sperm packet" during mating to ensure the safety of the wife and future eggs.
<h3>Light poison is not enough, and a few eggs in a nest is also learning</h3>
Of course, eggs also have a strategy to protect them. That's the number of eggs in a litter. First of all, the number of eggs in a nest can not be less than 3, if it is less than 3, aphids in the taste of whether it is poisonous, generally have to taste two or three, this pre-meal poison, will destroy the eggs; aphids generally eat twenty or thirty, then can the lamp moth lay fifty or sixty eggs in a nest? Of course not. In addition to the natural enemies of aphids, there are many eggs. Giving birth together is like gambling, the risk is too high, if you encounter a parasitic bee, it will be completely destroyed. So it is still more or less good, some a litter of five or six, some a litter of more than ten, some twenty or thirty, overall twenty or so a litter is the most credible, the survival rate of offspring is also the highest.
While using chemical weapons to protect eggs, the lamp moth also takes into account the strategy of balancing the number of eggs produced. The two-pronged approach is beneficial to the weeds from between. All in all, the knowledge in the worm egg is great. Changing a species, just like changing the martial arts sect, the tricks may be completely different.
The eggs laid by Fushou snails are brightly colored, which directly indicates that Lao Tzu is poisonous. Who dares to come and try it.
After a jumping spider spawns in Banna, it not only weaves a web to cover it, but also protects it personally for a long time
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