Question

Feeding habits are indicated on the phylogeny shown below for each species in a clade of birds. The outgroup species eats fruit. According to parsimony, which feeding habit was probably present in the ancestor at node 3? Node 1 Node 2 Node 3 Fruit Fruit Insects Insects A. fruit B. insects no prediction possible using parsimony

Answer 1

Parsimony is the idea which tells about lowest evolutionary changes to satisfy the probable phylogenetic tree. Here birds which are evolving from Node 3, feed on insects. So we can say the evolution of the habit of insects feeding is probably occurred at the Node 3 (immediate common ancestor) level or previously at any time when Node 2 was evolving to Node 3. So, according to the parsimony, the ancestor at Node 3 had a feeding habit depending upon insects.