On this episode of ID the Future, Casey Luskin takes a look at recent papers that challenge the Darwinian concept of a single, coherent "tree of life." As one paper from the journal Biological Reviews of the Cambridge Philosophical Society states, mounting evidence shows that "phylogenetic conflict is common, and frequently the norm rather than the exception." Luskin examines echolocation in bats and whales and asks--does biological similarity imply inheritance from a common ancestor?