Zooming in on Montjuic (v): gecko

Written by Lucy Brzoska

The craggy old gecko lies fossilized on the stone wall, flattened against the warm rock. A bug comes briskly by, and the gecko comes to life, peering down.

The bug quickens its pace, but the gecko’s tongue is faster.

Nothing more to do but lick one’s lips, settle back down into the warm rock, and wait to see what else turns up.

A Moorish gecko

Written by Lucy Brzoska

The richly patterned sandstone wall of Montjuic castle is full of chinks where a gecko might lie, safely basking in the sun. It takes a lot of staring to find one: you suddenly realise the dark patch has toes, and what might be a glinting shard of glass is an eye.

It’s the end of winter, and we all feel like basking in the sun. The Moorish gecko (Tarentola mauritanica) varies in colour – this one appeared almost black, effective for soaking up heat. At night, when actively hunting their prey, they turn pale and interesting.

The gecko let me approach and have a close-up look, perhaps confident that refuge was only a flicker away. Its eyes are split in half by a vertical pupil, sharply contracted against the strong light. Intricate veins cover the dark golden iris. Cleaning is done by a sweep of the tongue, since the gecko has no eyelids.

Perhaps because it sounds more exotic, the pet trade likes to refer to this species as the “Crocodile gecko”. I noted the allusion in the gecko’s bumpy skin. But the tail had a completely different texture: you could clearly see the fault line where the gecko had broken in two to escape from a predator. Once dropped, the tail continues twitching – a useful distraction device. I wondered if the tail, now in process of regeneration, would ever match the original one.

Just as humans have wanted to emulate the flight of birds, they envy geckos for their grip. Sticky hairs on prominent toe pads allow these reptiles to cling to the smoothest surface. A researcher into the phenomenon, interviewed in New Scientist, was flabbergasted by how “vastly over-engineered” they are: “One gecko could resist the weight of 130 kilograms”. Yet they can also detach themselves at lightning speed.