[gatagato]

So, how many legs does a kangaroo have? Four, right? Well, according to new research, the right answer is actually five. Yes, five.

A study published online Thursday says, when walking on all fours, kangaroos use their tails as a powerful fifth leg to help propel themselves forward. (Via Biology Letters)
To come to this conclusion, researchers from the University of Colorado Boulder studied five red kangaroos in a lab in Sydney, Australia, and measured the force their tails exerted on the ground. (Via )

They found, while the roos were walking on all fours, their tails acted as a fifth leg of sorts, working harder to propel the marsupials forward than their front and hind legs combined. Talk about getting a leg up. (Via )
One of the study's authors said in a statement, "We went into this thinking the tail was primarily used like a strut, a balancing pole, or a one-legged milking stool. What we didn’t expect to find was how much power the tails of the kangaroos were producing. It was pretty darn surprising."
As National Geographic points out, scientists aren't aware of any other animals that use their tails like this.
The study's authors believe that the kangaroo's use of its tail as an extra leg evolved to make its trademark hop faster and more efficient. (Via National Geographic)
But, as it turns out, walking and hopping aren't the only things the kangaroo's muscular tail is good for.
Red kangaroos are notorious for getting into scuffles with other roos. As Animal Planet notes, during a fight, the animals will deal out some nasty kicks while supporting all of their body weight on its tail.
And LiveScience points out kangaroos' tails help them balance and turn while they're hopping along.
Quite a "tail," right? The study was published in the journal Biology Letters.

http://news.nationalgeographic.com/n...als-australia/
http://www.wsbtv.com/news/news/scien...fth-leg/ngYXL/
http://rsbl.royalsocietypublishing.o...d-39ff6478e20c


Pentapedal locomotion in the red kangaroo. Kangaroos moved pentapedally across a force platform (checkered flooring). (a–d) A complete stride starting with contact of the front limbs (t = 0). Following the onset of front limb stance (a), the tail contacts the ground and the hind limbs begin swinging forward (b). After the hind limbs contact the ground again (c), the front limbs and then the tail swing forward (d). We measured the ground reaction forces (GRFs) generated by the pairs of limbs and tail over multiple strides (a–f). Tail forces were isolated after the other limbs no longer made contact with the force plate (f). The red, green, blue and black arrows represent force vectors associated with the front limbs, hind limbs, tail and reference body weight, respectively, for the represented trial. The checkered circles approximate centre of mass (COM) locations based on Alexander et al. [4] and are for illustrative purposes only.

[Desensitisation]

Um... this isn't fucking news to me. I've worked with roos, and anyone who has knows how fucking strong their tails are, and how they are used to move. I guess it's nice that they finally quantified the force involved, but if you've ever watched a boomer balance on their tail to lash out with their hind legs, it's no fucking mystery how strong it has to be to do that.

[candice81]

would love to work with them, Jelous!

[Nite]

Nothing in Australia is normal