I suppose if you asked a class of young children to paint a picture of a caterpillar, most would make it sausage-shaped and green.
That is the way we tend to think of caterpillars because those are the ones we see.
But what of those we never see? Here is an example of a stick mimic caterpillar.
Many moths have this type of caterpillar but we very rarely see them.
This particular one is the caterpillar of the Swallow Tailed Moth.
Adult Swallow Tailed Moths are gorgeous, very pale, almost transparent creations.
In contrast their caterpillars are more twig like than twigs, holding themselves rigid at an angle to a real twig and totally disappearing in the process.
Twig mimic caterpillars have evolved bud like growths and all the other charcateristics of real twigs.
Not for them mere camouflage based on cryptic colouration.
Evolution has taken camouflage several steps further with the leaf mimics.
Sure you can see this one as clear as day, but I would challenge you to find it a couple of minutes after I released it onto a bare winter shrub.
So kids, next time you are asked to paint a caterpillar, just paint a twig!