BI111 Lecture Notes - Lecture 10: Ecological Niche, Cardiac Glycoside, Monarch Butterfly
Document Summary
Several ways to describe this diversity in ways that integrate information on species richness and relative abundances. Shannon"s diversity index: accounts for both abundance and evenness of the species present. Genetically-based, reciprocal adaptations in species that interact ecologically. 2 unpalatable species with similar appearance relies on aposematism: warning signals. Batesian mimicry appearance resembling a poisonous/dangerous species due to random mutation. Second species evolved a second pattern of similar appearance trying to resemble the original poisonous species, in order to make the neutral species appear dangerous to predators. The host, poisonous animal suffers at a cost as others imitating them are decreasing the effectiveness of their phenotypes. Monarch butterflies are poisonous/unpalatable to predators as they retain cardiac glycosides from milkweed consumed as larvae. Viceroy larvae feeds on trees such as willows, poplars and cottonwoods which produce salicylic acid. It was found that if you eat viceroy, they are unpalatable as well and possess toxins.
