I have an idea for an alternate world where "mythical" creatures exist, but are based on biology. For instance a unicorn is more closely related to ovines (sheep/goats/deer) than to horses and dragons/drakes are similar to prehistoric proto-mammals than say Komodo dragons. Assuming that cockatrices are arboreal theropds, is there any reason why a species of them might have developed the ability to mimic venoms of other creatures and/or helpful/harmful chemicals produced by local flora?
- What would the drawbacks to this be?
- How would this particular species "sample" the compound/venom in order to produce it?
- What other considerations might I have overlooked?