How evolution turned ordinary plants into ravenous meat-eaters – Wired.co.uk

A species of carnivorous pitcher plant

AYImages / iStock

Meat-eating plants the world over, separated by thousands of miles and millions of year of evolution, share the same sneaky flesh-grabbing tricks down to a molecular level, a study has found.

By comparing the genomes of Australian, American and Asian pitcher plants the carnivorous flowering plants that entice insects into their tube-like leaves and drown them in a sticky liquid biologists could study how this deadly liquid trap evolved. In particular, the research team, headed up by evolutionary biology and plant genomics expert Victor Albert of the University of Buffalo, New York, sequenced the plants DNA to study the genetic differences between the Australian pitcher plants insect-trapping leaves, and its ordinary leaves used solely for photosynthesis. This revealed specific genes were only switched on in the tube-like leaves that generate the deadly serum, and those genes are used in the production of starches and sugars.

The serum was also compared to the insect-trapping juice of the plants distant relatives in Asia and America, and the liquid of a separate carnivorous plant. Despite evolving on different continents, the liquid in each plant had similar characteristics including enzymes used to break down bugs. The enzymes were not always destined to create bug soup, however. In non-carnivorous plants, they are used to break down a polymer called chitin as a defence mechanism against fungi that have chitin in their cell walls. Chitin is also found in the exoskeletons of insects, so it appears the carnivorous plant has a great deal in common with its relations - it has simply repurposed the enzymes to create a homegrown insecticide.

Subscribe to WIRED

Were really looking at a classic case of convergent evolution, said Albert, lead author on a paper describing the find, published in Nature Ecology and Evolution.

The study, though still leaving gaps in our knowledge relating to how certain mutations enable the enzymes to do their work, presents a leap forward in understanding how plants could have evolved from "ordinary", to meat-eating when habitats demand it and nutrients are scarce.

Original post:

How evolution turned ordinary plants into ravenous meat-eaters - Wired.co.uk