Sloth guts are designed for hanging upside down, study finds

Apr 23, 2014
A three-toed sloth (Bradypus) plays at the Aiunau Foundation in Caldas, Colombia on September 15, 2012

Three-toed sloths have a unique abdominal design—their innards fixed to their lower ribs to avoid squashing the lungs while hanging upside down, a study said Wednesday.

The South and Central American forest dweller, also known as the brown-throated , spends a large part of its life hanging from its to reach young, tender leaves growing on the tips of branches, as well as to groom.

With its slow metabolism, it may take the sloth a month to digest a single leaf, and it can store a third of its bodyweight in urine and faeces—which it deposits about once a week.

"This means that the stomach and bowel contents make up a considerable proportion of their body mass," said Rebecca Cliffe of the Swansea Laboratory for Animal Movement in Wales, who co-authored the study in the Royal Society journal Biology Letters.

"With their limited energy supply, it would be energetically very expensive, if not impossible, for a sloth to breathe whilst hanging upside down," she told AFP.

Cliffe and a research team say they believe they solved the riddle: numerous unique adhesions in the abdomen anchor organs such as the liver, stomach and kidneys, thus preventing them from pressing on the diaphragm when the sloth is inverted.

"These seemingly innocuous adhesions are likely to be important in the animal's energy budget and survival," said the study.

They could reduce a sloth's by 13 percent, added Cliffe.

Explore further: Amphibian chytrid fungus reaches Madagascar

More information: Mitigating the squash effect; sloths breathe easily upside down, Biology Letters, rsbl.royalsocietypublishing.or… .1098/rsbl.2014.0172

add to favorites email to friend print save as pdf

Related Stories

Researcher IDs Ice Age sloth bone in Colorado

Nov 07, 2010

(AP) -- Scientists excavating an Ice Age ecosystem in the resort town of Snowmass Village say they have found the first Jefferson's ground sloth ever discovered in Colorado.

Identifying sloth species at a genetic level

Jan 03, 2012

Identifying species, separating out closely related species and managing each type on its own, is an important part of any animal management system. Some species, like the two types of two-toed sloth, are so close in appearance ...

Sloth movement secrets revealed

Sep 10, 2010

( -- New studies of the movements of sloths have revealed more information about how they move around in the trees, traveling upside down.

Recommended for you

Cats put sight over smell in finding food

15 hours ago

Cats may prefer to use their eyes rather than follow their nose when it comes to finding the location of food, according to new research by leading animal behaviourists.

Feds spot third baby orca born recently to imperiled pods

16 hours ago

(AP)—U.S. scientists following endangered killer whales from a research vessel have spotted a baby orca off the coast of Washington state, the third birth documented this winter but still leaving the population ...

Bumblebees make false memories too

18 hours ago

It's well known that our human memory can fail us. People can be forgetful, and they can sometimes also "remember" things incorrectly, with devastating consequences in the classroom, courtroom, and other ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

5 / 5 (2) Apr 23, 2014
Your title editor does not understand evolution if he/she thinks "design" is correct.
not rated yet Apr 23, 2014
What was the editor thinking ??

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.