In the 1960’s the noted Smithsonian photographer Kjell
Sandved had fanciful interpretations of butterfly wings. His calendars were
very popular at the time. I’m sure he would concede that his interpretations of butterfly wings were not really what nature had intended! But
it does beg the question of messages and interpretation.
On the light sheet, all bets are off. Every species is
present on an equal basis. camouflage, odd resting postures all mean nothing or very little to potential predators. It’s instructive to observe which creatures (mostly moths are used here) are
taken and which are not. Birds find the light sheet opportune for easy pickings
but the insect-eating marsupial Antechinus and lizards (mostly geckos) can
often be seen harvesting the bounty.
The hungry vertebrates are not influenced by patterns on the
moth wings as they view them on the light sheet—or are they. Those moths that would
be camouflaged on trees or leaves are the ones that are taken first. More brightly coloured and
non-camouflaged species are left alone. They are there all day. I’ve never seen
a bird attempt to eat one of these moths. Whatever it is that influences their
judgement, it is fairly well fixed and these creatures are left alone
(avoided?). [My mothologist friend, the word merchant, is very careful about
the use of words in our interpretation of natural observations].
Two moths that are not eaten by birds and lizards
This arctiid is also left alone by birds but the Green Tree Ants have no problems tearing it to shreads
Patterns and postures are probably genetically set and learned by birds and lizards early in their lives. They seem to know what to avoid and what to try. Colours play a big role. In many groups there are mimics that are edible but possess patterns that resemble the distasteful ones. As long as their numbers are lower than those of the "models" their protection is assured. I have not observed this situation with respect to the moths above.
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