Professor Ceiling Cat continues to be distressed at the lack of interest (reflected in comments, at least) on the science posts: those posts that are the hardest to write. Nevertheless, he persists.

Here is a likely example of aposematic (warningly colored) mimics in different orders of insects having evolved to resemble each other (tweet courtesy of Matthew Cobb).  This phenomenon is well known in biology, and is known as Müllerian mimicry after the German zoologist Fritz Müller.

If distasteful, noxious, or dangerous species share a common predator, they may evolve a convergent pattern or color that the predator recognizes and avoids. The presumed advantage is that if these species have a common pattern, the predator has to undergo less “learning” to recognize and avoid the shared pattern. What that means to one of these insects like those below is that if an individual of species 2 gets a mutation that somehow resembles a pattern that predators have already learned to avoid in species 1, it has a reproductive advantage over individuals of species 2 with some other aposematic mutation. Do you see why that is? It’s because the first few individuals of species 2 with a different aposematic pattern stick out in the environment, and the predator hasn’t yet learned to avoid them. Learning means that it has to sample the insect (likely killing it) before it learns to avoid the new pattern. You have a survival advantage if you fit in to an already-evolved/learned system rather that starting another one with a mutation that hasn’t been “learned.”

This, biologists presume, is the reason why members of different species evolve to resemble each other when they’re all noxious to predators.

Here we have species from three different insect orders—Coleoptera, Diptera, and Lepidoptera—which have evolve a common orange and black striped pattern.

A really fascinating case of mimicry between lycid beetles, flies, and moths. Specimens collected by Robin Andrews @VT_Biology and identified by Grant Schiermeyer @VT_Entomology #naturalhistory https://t.co/h7pIQgmoq6 pic.twitter.com/VTen0mLsFO

— VT Insect Collection (@VTBugCollection) January 8, 2018

While we can’t observe the evolution of this convergent pattern, we can make predictions from our evolutionary scenario.

First, these insects have to share a common predator: that is, there should be one or more species of predator that lives in the area that all these species inhabit, and has learned to recognize and avoid the pattern. That, of course, can be tested. (There are some twists here, but not important enough to mention.)

Second, that common predator has learned or can be taught to learn to avoid the pattern.

Third, if you have trained a predator (say, a naive, hand-reared bird) to avoid the pattern, introducing the predator to a different species with the same pattern should show that it’s avoided more often than a brightly colored species with a different pattern.

I know that the second prediction has been tested and confirmed for some aposematic insects, but I’ve no idea whether the first and third have been for members of Müllerian mimicry rings. (Hypothesis three has been tested and confirmed for members of singe aposematic species.)

The important thing is that the evolutionary hypothesis is testable. Creationists, of course, could just say “God made a group of insects this way so they’d survive”, but that assertion can lead to different predictions. I won’t go into those, but perhaps you can think of some.

Julius Csotonyi, described by Wikipedia as a Canadian “paleoartist” (illustrator of ancient life) and a natural history illustrator, has done some fantastic artwork, including producing dinosaur images for Canadian coins. You can see a lot of his art at his website. But now Csotonyi may have detected a case of Batesian mimicry between a tree frog and a predatory snake (an emerald tree boa).

I’ll just show you his Facebook posts on the issue, which I have permission to put up. Julius sees a striking resemblance between the waxy monkey tree frog and a coiled emerald tree-boa, including the eyes, the folding of the skin, the color, and the white stripes.

The range overlap is some evidence for his thesis, though mimicry of a model can still have evolved when both now live in different places if the predator is migratory or if the mimicry is an evolutionary relic of a bigger range overlap that occurred long ago.  To me, the frog’s eyes, its posture, and the weird shape of the top of the head also resemble the snake.

I’m calling this a putative case of mimicry, but of course to be sure of this one would have to test it. For one thing, this is usually thought to work when the frog predator learns to avoid the snake through bitter experience, and then transfers that learning to avoiding the frog. If encounters of the frog predator with the snake were always fatal, no learning to avoid the snake appearance would be possible But predator avoidance could also be an innate response. That is, those frog-eaters who lived because they had genes that made them avoid approaching the snake because of its pattern,  and thus more likely to run away when they saw it, would be less likely to be eaten. That would produce an evolved rather than learned fear of things that look like this boa. Batesian mimicry need not always require a learned avoidance.

What do you think? Does this look like mimicry?  Put your answer below (we don’t know the truth, but herp people might take a guess). This may be the first case of Batesian mimicry involving an amphibian as the mimic and a snake as the model, but I’m not sure if other cases are already known.

As your reward for guessing, here’s another mimicry cartoon from SMBC (artist Zach Weinersmith) found by reader David.

Now what’s the erroneous assumption of this case of mimicry.?