You’ve probably heard the song walk like an Egyptian, but the roly-poly trot of the long-beaked echidna is equally song worthy.
If you picture the walking style of most mammals and even us humans, the limbs work in diagonal pairs. While we move our right hand with our left leg and vice-versa, it seems the long-beaked echidna is doing it differently.
In the same pattern lizards use, this echidna walks with both legs on the same side moving together, rolling from left to right. The synchronisation of the limb pairs however isn’t as exact as in lizards and because of this the whole thing ends up looking like more of a trot. See the video!
It seems incredibly odd for this animal to walk this way. Its body must tilt from side to side, a strain that animals walking with their limbs in diagonal pairs don’t have to endure. It also can’t run, probably because of the problems balancing.
To achieve this walking pattern without being flat and sprawled like a lizard, the Long-Beaked Echidna must walk with a very narrow stance and their shoulder and hip joints have evolved to be much closer to their spine to accommodate.
This weird way of walking is most easily recognised in the Long-Beaked Echidna but has actually been observed in all three species of monotremes – the most ancient of extant mammals including the Short-Beaked Echidna and the Platypus, both found in Australia. Scientists believe this evidence could suggest the now common mammalian walk, with diagonal limb pairs, was actually derived from this lizard-like way.
So maybe our long lost ancestors walked with their right hand and right leg followed by their left hand and left leg but try it now and you’ll notice how much concentration it takes and how quickly you’ll fall back into your natural right with left limb pattern.
And you’ll also look odd, just like the Long-Beaked Echidna.
Gambaryan, P., & Kuznetsov, A. (2013) An evolutionary perspective on the walking gait of the long-beaked echidna. Journal of Zoology, 290(1), 58-67. DOI: 10.1111/jzo.12014