Reason for BST chrysalis color
I have 6 BSt chrysalides, and 5 are green, and one just needs to be different, and is brown.
They all are using the same materials to pupate on--I have one of those butterfly cages. Three are on top--2 are green, one is brown (the rest have pupated on stems down below).
I remember this being discussed here--and there questions about whether it related to whether the butterfly would overwinter or it was related to what the caterpillar pupated on.
I did a little internet search, and found this bit on Wikipedia (Wiki's source is Butterflies of Canada). Article states that it has to do with "genetic balance that ensures the majority of pupae will blend" into the background.
Makes sense--if caterpillar pupates somewhere brown, then it's likely to survive.
What do you all think? Any other reasons? I like learning these things. :)
Here is a link that might be useful: Wiki article