Tackling one of the most difficult and delicate of the evolutionary questions, this challenging book summarizes the more recent results in phylogenetics and developmental biology that address the evolution of key innovations in metazoans. Divided into three sections, the first considers the phylogenetic issues involving this area of the tree of life and the elucidation of those relationships that continue to trouble taxonomists. The second section considers the developmental biology of metazoan evolution including the development of the nervous system, sensory organs, and physiological...

Ever since the recognition of the Neanderthals as an archaic human in the mid-nineteenth century, the fossilized bones of extinct humans have been used by paleoanthropologists to explore human origins. These bones told the story of how the earliest humans--bipedal apes, actually--first emerged in Africa some 6 to 7 million years ago. Starting about 2 million years ago, the bones revealed, as humans became anatomically and behaviorally more modern, they swept out of Africa in waves into Asia, Europe and finally the New World.
Even as paleoanthropologists continued to make important...