Wednesday, January 26, 2011

Tiny Borneo bats use carnivorous pitcher plants as living toilets

Birds may bomb cars with airborne droppings, but bats apparently use living toilets made of carnivorous plants, gracing them with their fecal matter, scientists find.

Pitcher plants get their name from the long juglike structures they form from rolled-up leaves. These pitchers serve as pitfall traps, with digestive fluids to liquefy any hapless victims (typically insects) that fall in.

Scientists recently discovered that small mammals known as tree shrews on the Southeast Asian island of Borneo don't end up as doomed victims of the carnivorous plant — instead, they sit on the rims of one such pitcher plant, Nepenthes lowii, and then poop inside.

As ignoble as this might seem, this is a win-win situation for both the pitchers and tree shrews. The plants cover the pitcher lids with nectar that the critters readily lick for nourishment, while the excrement serves as much-needed fertilizer. (This is why carnivorous plantsnormally trap insects — to get valuable nutrients.)

Now it turns out pitcher plantsare not exclusive bathrooms. Scientists have discovered the small woolly bat Kerivoula hardwickii uses a different type of pitcher in Borneo, Nepenthes rafflesiana elongata, as a lavatory and home as well.

Bat roosts

Tropical ecologist Ulmar Grafe at the University of Brunei Darussalam in Brunei first started working on the island of Borneo investigating how tadpoles can survive within the fluid of pitcher plants.

"It was a hot and humid day in the peat swamp forest and a student calls out, 'Ulmar, have a look at this — there's a bat in this pitcher,'" Grafe recalled. "We squeezed it out the top, and it was alive and well, obviously using the pitcher as a daytime roost."

Other people had seen bats roostingin the pitchers but they put it off as coincidental. "We were seeing it too often, however," Grafe said.

The pitchers of N. rafflesiana elongata are actually poor insect traps, capturing up to seven times fewer insects than typical varieties and possessing relatively little in the way of insect-attracting scents and digestive fluid. As such, "maybe the pitchers are modified in a way that attracts bats," Grafe said. "Bat roosting may not be coincidental."

Continue reading (Incl. Pic) at: Tiny Borneo bats use carnivorous pitcher plants as living toilets
.
.

Labels: , ,

0 Comments:

Post a Comment

<< Home