Evolution of Plants into Carnivores

409

An insect can be very unlucky to land on the leaf of a mouth-like Australian Pitcher plant because it will experience an offensive end. The prey of this plant gets into the pitcher, a vessel-like organ, where a dedicated cocktail of enzymes embarks on digesting the victim.

By studying the genome of the pitcher plant, and making comparisons with its fluids of eating insects to fluids of other plants, scientists have concluded that the meat-eating plants in the whole world have a similar deadly molecular recipe, although they have a separation years of evolution.

Victor Albert, a scientist at the University of Buffalo in New York, says that they are looking at classic cases of convergent evolution. He deputized the nature evolution and ecology study. Carnivorous plants are all over the family tree of flowering plants. The pitcher plant is native to the silver coastline of southwest Australia and is related to the starfruit more than other pitcher plants in Southeast Asia and America. This suggestion shows that carnivory is repeatedly evolving in plants, perhaps for coping with soils with scarce nutrients. Albert says that these plants try capturing phosphorus and nitrogen from the prey.

The Australian pitcher plant produces noxious pitcher leaves that resemble toothy grins and flat leaves. Following the sequencing of the genome of the species, Albert and his team identified genes which get activation differently between these leaves and the other non-carnivorous leaves. These genes were involved in processing sugars and starches for nectar production for luring insects to death, and genes for encoding waxy substances for making it hard for the insects to escape the pitcher.

To make a determination on how the pitcher plant eats its prey, scientists sampled digestive cocktails from a range of unrelated carnivorous plants including the Cephalotus. They identified thirty-five proteins by use of mass spectrometry. Most of these proteins relate to those found in flowering plants used for fending off pathogens. Therefore, these plants produce enzymes for breaking down the polymer called chitin, which acts as a fungi defender, which makes its cell wall from the chemical. Conversely, Albert suspects that carnivorous plants and pitchers have diversified the purpose of these enzymes to digesting the exoskeletons of the insects, which are made of chitin.

In a new analysis, the research team found that in carnivorous plants that are distantly related, including all pitcher plants, the deployed genes for making the digestive fluid proteins come from a common evolutional origin. A good number of these genes have evolved independently changing their enzyme shape and encoding similarly in different species. The scientists do not have a proof for the same, but they think that mutations will help in stabilizing the enzymes when present in the digestive fluid.

Aaron Ellison, who is an ecologist at Harvard Forest says that researchers have come to appreciate convergent evolution in carnivorous plants and that the study demonstrates how this convergence can take place.

Possessing the ability to feed on insects is useless if the plant cannot trap one, Albert says that it is at this point that evolution brings different solutions. The Venus fly trap ensnares its prey, while bladderworts immobilize its victims by use of their tiny suction cups. In the book, Insectivorous plants, by Charles Darwin, there are tentacle drawings that the sundew uses to pin insects on its leaves. Darwin wrote the whole of this book on plants that are carnivorous.