I came across an interesting set of photos which depict a toad's reaction
when presented with a late-instar Deilephila elpenor (Sphingidae) caterpillar:
http://www.warrenphotographic.co.uk/07328-toad-defensive-at-elephant-hawkmoth-caterpillar
http://www.warrenphotographic.co.uk/07327-toad-defensive-at-elephant-hawkmoth-caterpillar
According to the photographer the toad has adopted a
"snake-defensive" posture, however I'm unsure of the validity of this
statement. No doubt that snakes are important predators of frogs and toads, but
I know that large frogs and toads also attack and eat small snakes. This is
clearly an artificial setting, but it is plausible that frogs and toads might
come across a late-instar Deilephila elpenor caterpillar as they
pupate amongst leaf litter and other debris.
More information about the natural history of Deilephila elpenor can be found here.
Interesting! I wonder if a toad would react similarly to a caterpillar without eyespots? It would be neat to test if it were the general shape and size of the caterpillar that mattered, or if it needs eyespots to illicit that response.
ReplyDeleteGood question. Many caterpillars with eyespots assume a defensive posture when they feel threatened and this may enhance the fear/intimidation effect of the eyespots. I am really interested in the morphology-eyespot interaction and I am currently working on a few projects investigating that question right now - not with toads in particular though ;)
ReplyDeleteAlso check out this post by Ed Yong:
ReplyDeletehttp://blogs.discovermagazine.com/notrocketscience/2011/08/01/harmless-snakes-avoid-danger-by-mimicking-the-triangular-heads-of-vipers/