The carnivorous pitcher plant is nature's own honey trap, luring insects to their doom with drops of nectar and other enticements. But once an insect comes to call, pitcher plants have a problem: how to make sure their prey doesn't escape.
Now, researchers have discovered an ingenious insect-trapping mechanism, or rather two, in a South American pitcher species. The throat of the little-known Heliamphora nutans, new research shows, is covered with a pelt of tiny, precisely oriented hairs that prey can't easily ascend.
The hairs also help to create a slippery, wet film on the pitcher's inner walls, making it nearly impossible for the plant's victims to get a grip. Instead, they plunge into the bottom of the pitcher, where they drown in a pool of water.
Other carnivorous plants also resort to strange techniques for seizing prey, says Jonathan Moran of Royal Roads University in Victoria, British Columbia, Canada, but the features described in the new study are "very, very sophisticated. It's not perhaps the most outrageous method of doing it, but it certainly seems to be very effective."
It's not easy to study this kind of pitcher in the wild, says first author and plant biologist Ulrike Bauer of the University of Cambridge in England. H. nutans lives atop high plateaus in the wilds of southeastern Venezuela, an area dubbed "The Lost World." To access the area, scientists need a helicopter and a permit the Venezuelan government is reluctant to grant.
As a result, no one knows H. nutans' precise prey, only that it mostly consumes ants. So Bauer and colleagues worked with specimens of the plant from the collections of London's Royal Botanic Gardens, Kew. -- ScienceNOW