Saturday, September 19, 2015

Date with a thorny devil

Thorny Devil Moloch horridus
A gravid thorny devil catches some rays.

Not much beats seeing an animal in the wild. A little while ago I was part of a team undertaking some fieldwork in the Tanami Desert in Central Australia. You can never plan these things, and even among scientists one is considered to be “jinxing” one’s chances if one utters a desire to see an animal. Which is a topic for a whole other discussion. But I did say, to no one in particular, “I’d LOVE to meet a thorny devil” on the drive out from Alice Springs.

Thorny devils, named by someone who didn’t appreciate their beauty (Moloch horridus), are central Australian native agamids that resemble a medieval weapon.

They are active in the daytime but they’re very well camouflaged in the environment so not always easy to spot – unless they’re sunbaking on bitumen in which case it’s super easy.

Not that we spotted this one. She came to us. A visitor turned up with a thorny devil who had been picked up by some kids and needed to be released. So we saw a thorny devil in the wild…albeit reintroducing her into a suitably sandy location.

How do we know she was a she? Well, she looked a little bit gravid (ie pregnant). They lay eggs, and the ladies are usually a bit bigger than the blokes.

Gravid thorny devil Moloch horridus
A gravid thorny devil, Moloch horridus.
If you’re not sold on TDs, here are some nifty things that might change your mind.

  1. They have a “false head” which is displayed to predators when they dip their real head. Although one questions the evidence that the purpose of this soft tissue structure is to act as a false head. Because eagles and goannas tend to eat TDs whole. Anyway, one explanation of the lump behind their head is that it acts like a false head. Certainly looks similar to the head.
  2. They use their spiky skin to drink. They stand in a puddle or water source, or dew collects on them, and the water is drawn by capillary action along groves in their skin to their mouths.
  3. They dine only on ants, making them “myrmecophages” – which should really be “antphages”. Apparently, if you crush their stools between your fingers (not an activity for everyone) you find digested bits of ants.

It was an honour to spend some time with this magnificent creature, until we found a suitably sandy spot to release her. Here’s hoping she lays a clutch of beautiful eggs.