Wednesday 19 March 2014

Spectacled Lizard

Image: Esteban Alzate
Bachia bicolor
Here we go again! The tempestuous, on-again-off-again relationship between lizards and their own legs continues. What a saga!

We've seen it before with the skinks, that huge family of lizards that contains everything from long, dainty ankles and powerful thighs, to stumpy limbs and missing toes, to some species with no legs whatsoever.

Image: Geoff Gallice
Cercosaura oshaughnessyi
This time we're looking at another family of lizards which contains a couple hundred species, most of them under 15 cm (6 in) long, and all found in Central and South America. It's Gymnophthalmidae, commonly known as the Spectacled Lizards.

Gymnophthalmidae means "naked eye". That's why eye doctors are called ophthalmologists and why the official uniform of every gym in the world is a birthday suit. Thankfully, they're very lax with enforcing that particular rule.
Image: Wikimedia
Euspondylus oreades
Both "naked eye" and "Spectacled Lizard" refer to their transparent lower eyelids. They can see with their eyes closed! I guess they're more like contact lenses, really. Much more difficult to lose, though; not many people fall to their hands and knees to find their lower eyelid. We have so much to learn from nature.

Spectacled Lizards live in a huge variety of habitats, from rainforests to halfway up the Andean mountains, and from desert-living to semi-aquatic.


Lots of them have big legs with long toes but, just like the skinks, many of them have become incredibly elongated with ridiculously long bodies and absurdly long tails. Once that happens, it seems that legs become increasingly useless. Their unending physique does all the work for them.

Image: Erfil
Bachia dorbignyi
So there are many species with adorable little baby hands or no limbs at all. A lot of them lose their legs in the usual way, with forelegs always in a more advanced state of diminution. The hind legs take longer to disappear, perhaps because they're bigger, stronger and more useful since pushing from behind is more effective than pulling from the front.

But species in genera like Bachia do it the other way round. Their hind limbs are more reduced than the front ones. They've found a unique way of becoming legless! It's always nice to have options. Personally I'd just keep the legs but I guess I'm just not as daring as a lizard.

7 comments:

Esther said...

That third lizard is giving me the evil eye.

Joseph JG said...

Probably eyeing up those limbs of yours!

TexWisGirl said...

very funky!

Joseph JG said...

Yup!

Crunchy said...

These guys are quite the... spectacle?

...I'll see myself out.

Lear's Fool said...

*bows to crunchy*

Joseph JG said...

You're bad, Crunchy.

Real bad.