Insect that has evolved to recognize carnivorous plants

[Ahmed Abdullah]

Obviously in a biome consisting of high density of carnivorous plants any insect that can recognize these plants or at least recognize organs associated with carnivory will get fitness advantage. So it seems a very natural thing to evolve from insects point of view. Has it happenned? If yes, what are some of the examples? If not, why it hasn't happened?

 

[BillTre]

Some insects that have evolved beyond mere avoidance and have developed symbiotic relationships with pitcher plants. There are ants that live in close association with the particular plant.

Of course, not all insects have done this and become prey of the plant.
The plants in turn have evolved features to lure in, attract, and trap their prey more efficiently, so there is an evolutionary arms race going on.

The relative strengths and success of selection for avoidance (by the insects) and entrapment (by the plant) will depend for one thing on the extent to which the pitcher plant is major element in the life of the insect.
If an insect lives its whole life on a plant, then its frequent interactions with the plant will consistently provide selective forces to avoid the evils of the plant.
If an insect ranges far over a variety on area and spends relatively little time in the region of some carnivorous plants, then it could be expected to be less strongly selected to avoid the carnivorous plants.

 

[jim mcnamara]

First, there is no 'why' to evolutionary results. Natural selection is the result of a lot of random events. Example: a massive flood wipes out a small population of insects that have other wonderful adaptations. They are gone forever. Whatever those bugs were adapted for, surviving floods was not among the traits. The Earth has had major and minor catastrophes and long/short term climate changes that all have driven natural selection.

Second, carnivorus plants are rare and usually with limited population size a dn distribution, often under unfavorable conditions where there is almost no nitrogen in the soil. Swampy areas, for example. Example: Venus flytrap (Dionaea spp.). The amount of nitrogen they get from insect protein makes up the difference between just barely eking out a living and surviving well enough to assure greater reproductive success. And the amount of insects they capture is small, so they exert very little selection pressure on insects to avoid them. It takes about 10 days for a leaf trap to digest one bug. The bugs have many and much bigger problems. And insects pollinate the flowers, ironically.

First, there is no 'why' to evolutionary results. Natural selection is the result of a lot of random events. Example: a massive flood wipes out a small population of insects that have other wonderful adaptations. They are gone forever. Whatever those bugs were adapted for, surviving floods was not among the traits. The Earth has had major and minor catastrophes and long/short term climate changes that all have driven natural selection.

https://en.wikipedia.org/wiki/Venus_flytrapThere is no why answer to alfalfa's "lifestyle", versus the Venus flytrap way of doing things. Except to say that somewhere, sometime thing allowed those methods of getting extra nitrogen to get a small foothold. And they persisted and flourished because they could do better than their less adapted cousins.