Sep 13, 2021 16:00:00

Butterflies that 'suck the body fluids of the same species alive' are confirmed, nutritional supplements to make female-attractive pheromones

Monarch butterflies, which are widely distributed in the Americas and the Pacific Islands, are known in North America for their habit of migrating northward and southward within a year. A terrifying behavior of 'sucking the body fluids of larvae alive' was confirmed in such a monarch butterfly, and a paper was published in the academic journal 'Ecology'.

Kleptopharmacophagy? Milkweed butterflies scratch and imbibe from Apocynaceae-feeding caterpillars --Tea ---- Ecology --Wiley Online Library
https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.3532

Butterflies feed on live young to steal chemicals for'wedding gifts' --Scimex
https://www.scimex.org/newsfeed/butterflies-feed-on-live-young-to-steal-chemicals-for-wedding-gifts

Milkweed butterflies tear open caterpillars and drink them alive | Live Science
https://www.livescience.com/butterflies-drink-their-babies.html

Monarch butterfly larvae accumulate poison in their bodies by eating the leaves of a plant called milkweed, which contains harmful alkaloids, and prevent them from being eaten by their natural enemies, such as birds. Since this poison persists even when it becomes an adult, pupae and adults are informed that they have poison to foreign enemies with a bright aposematism.

In addition, adult males use alkaloids to produce pheromones, and the produced pheromones are transferred to females during mating. In order to produce the pheromones necessary for mating, adult males take the action of scratching milkweed leaves with small claws and sucking the liquid containing alkaloids that came out from inside.

However, in December 2019, a research team of Yi-Kai Tea and others enrolled in the doctoral program at the Department of Life Sciences at the University of Sydney found that several wolf madara scratched the body of a larva in the Tangkoko Batuangs Nature Reserve in North Sulawesi. He said he observed that he was sucking the body fluid that oozes from the wound. If you look at the following pictures actually taken by the research team, you can see that the adult monarch butterfly is attacking the larvae.

In addition, there are cases where multiple adults flock to one larva ...

Some individuals have been found to suck body fluids from dead larvae. Adult monarch butterflies sometimes continued to inhale body fluids for several hours, and even if researchers tried to distract them by touching them, they were still inhaling body fluids. The research team says they have named the series of actions 'kleptopharmacophagy'.

Previously, it was reported that monarch butterflies suck body fluids of another species of dead insects, but this is the first time that larvae of the same species have confirmed that they also suck body fluids alive. 'The larva is essentially a'bag of softened leaves'and has the same chemicals that the adult monarch butterfly is looking for. For adults, it's just a chemical that feeds. It may be an alternative source of larvae. '

The researchers argue that the behavior of adults sucking larvae's body fluids does not fit into traditional models of predation, parasitoids, and symbiosis, raising questions about evolution. On the other hand, he said that there is a possibility that 'adult monarch butterflies happened to be attracted to the leaves of milkweed with larvae, and when the claws accidentally injured the larvae, body fluid containing alkaloids came out from the inside and sucked.' I did.