I responded to this on Clark's forums but I'll add it here too.
Bennet is one of (Possibly THE) most educated and respected field biologists in the world, he's done some truly amazing work with varanids which automatically takes him into contact with other species. There aren't all that many people, even well respected ones, where I accept anything they have to say at face value, even if it contradicts established beliefs or avaliable circumstantial evidence- Bennet is one of them though.
"Genes, Like Leibnitz's monads, have no windows; the higher properties of life are emergent... And once assembled, organisms have no windows." - Edward Wilson, Sociobiology