MartinV writes:
What I claimed is that mutation and natural selection/neutral drift do not lead to speciation. It would be observed if it were true.
Fascinating, I guess you disagree with this
Observed Instances of Speciation
Dawkins mentioned only mutation in dogs. The other question is why we can't breed lizards or tigers. Either there are not alleles that can be used for domestication or these species do not mutate.
Perhaps the question is not so much can't but rather why. Why would our ancestors want to breed tigers, which are not communal hunters like dogs? After all, even the most nature-isolated person should be able to see that hunting dogs and humans are a serendipitous combination.
Ever heard of a hunting lizard that puts food on a human plate?