Tree-climbing crocs have allowed us to turn back the clocks and offer scientists important clues to the behaviour of extinct species.
A joint Australian-American study has shown that although it's long been suspected that ancient crocodile species could climb trees, it has never been properly examined in existing species, who are "doing some quite remarkable things", said Adam Britton, senior research associate at Charles Darwin University.
Crocodiles are surprisingly agile, and climb trees to get out of the water to escape predators, competitors, or to find a place to bask in the sun when surrounded by dense vegetation.
"They may have competition from other crocodiles sitting in the prime basking areas, so if you're a crocodile that wants to get out and bask you've got to find somewhere else - climbing out on a tree branch is the perfect way to do it," Dr Britton told AAP.
He says the elevation also gives crocs a better view of what's in the water.
"If the branch is overhanging the water you can escape very easily; you literally just fall off the log and bang, you're in the water."
Fortunately, in Australia it's the mostly harmless freshwater crocodiles that scale trees, and not their more aggressive saltwater counterparts.
"If a four-metre crocodile was chasing you there's no way that would be able to get up a tree easily," Dr Britton said.
"As they get bigger, their limbs get proportionally smaller relative to their bodies, and just don't have the strength to pull them up trees."
Observing this behaviour in modern crocodiles has provided important clues to how extinct species might have lived, he says, and shows that despite the fact that crocodiles don't look like they could climb trees, they certainly can - and do.
Just looking at a fossil's leg size and shape "doesn't necessarily tell you what the animal's behaviour is, because the behaviour of an animal doesn't fossilise", Dr Britton said.
"Knowing they can climb increases the range of possible behaviours these fossil animals could do."
