Some plants make caterpillars eat each other

Plants have few ways to protect themselves from insects that want to eat their leaves. Recently, scientists have discovered that some species of plants in a rather tricky way can provoke caterpillars to eat their brethren! How does this happen?

Do not eat me, eat it!

According to a study published in Nature Ecology and Evolution, the cannibalism of caterpillars is pushed by the special chemicals that plants secrete.

The authors studied tomatoes, which, like many other plants, under stress or damage, secrete a special chemical substance - methyl jasmonate. Of course, when a caterpillar tries to eat you, you are stressed, so uninvited guests cause a strong flash that creates a kind of “chemical camouflage” on the leaves and stems.

In addition, methyl jasmonate spreads through the air and is absorbed by other plants, warning them of the danger. After such a signal, the neighbors of the attacked plant also begin to secrete this substance.

Researchers are confident that studying the mechanisms of plant action on caterpillars will allow farmers and gardeners to develop better pest control methods.

Natural selection

But how rare are such cases among insects? Honestly, for many species, a fellow snack is a common thing. Many insect larvae are eaten by less fortunate brothers. The tradition of female praying mantis has become famous for its "suitors" - by the way, many insects, including cockroaches, practice this approach. And some species of flies can begin to hunt each other with increasing temperature.

In 2008, a study was conducted that explained why the locusts are constantly striving forward: it turns out that the "people in front" simply feared that their back would be bitten off to gather behind. A 2010 survey study says that many typically herbivorous insects, such as caterpillars, can switch to carnivorous cannibalism if there isn’t enough food to feed the entire population.

Scientists believe that such a mechanism has a beneficial effect on the evolutionary development of the colony: by eating weaker, stronger individuals do not compete with them for a meager diet, and also retain the remaining ones for more successful times.