So there was a lizard clinging to the side of the bathroom wall. My sister screamed. My mum yelled and so I have the unpleasant task of removing it from the wall.
The strange thing is the lizard was already dead. But it still remain stuck to the wall, so that’s Mystery #1. Mystery #2 is the pose which the dead lizard has adopted - his head was arching upward, as if it was looking around.
If it was dead, shalln’t it fell off? How does a dead lizard keeps its head up?
Thanks in advance!
Before we start guessing at answers, give us a bit more information.
What kind of lizard? Anole? Skink? Gecko? (What continent do you live on?)
As to the pose: it was on a wall, OK, head toward the floor? Head toward the ceiling? Head and tail horizontal?
At a wild guess, it was still on the wall because whatever mechanism that species uses to cling to walls (sticky pads, for example) do not require muscular exercise to work, so a live and awake lizard, a live and sleeping lizard, and a dead lizard all have he same (near zero) chance of falling off a wall. Similarly, if it clings by getting its claws around projections or into crevices, it probably has musculature that maintains its position while sleeping. If death did not happen to “open” those muscles, then it will continue to “cling” after death.
If it died in its sleep, various muscle twitches or physiological reactions might cause the back or neck muscles to contract, pulling the head “up” in an attitude of watchfulness.
My guess is that the lizard was a gecko, which uses intermolecular Van der Waal forces to cling to walls, or even glass. These forces are created by the mechanical structure of the toe pads, and do not depend on the lizard being alive to function.
Post-mortem contraction of ligaments causes the neck to arch up after death in many animals, as is seen in many fossils.
My pet anoles have sticky toes too. I’ve never had one die while sticking to anything, but those little toes can hold on very tightly. It’s difficult to pry one off of something without hurting it, and if one decides to stick to your hand, you can shake your hand all you want - they won’t come off.
I’ve found that when they are stuck to perfectly smooth surfaces, however, water will interrupt the adhesion.