Quoting "Mickey Rowe;893-2446" <mrowe@lifesci.ucsb.edu>:
Tom (or Dawkins?) is referring only to genetic structure and not to functionality, then you could say that all mammals are at least dichromats. The marine mammals, owl monkeys, and procyonids I mentioned in a previous post all have genes for two opsins. It's just that the S-cone opsin genes have premature stop codons which render them non-functional. Just like the opsin genes of humans with severe forms of color deficiency.
-- Nick Pharris Department of Linguistics University of Michigan
"Creativity is the sudden cessation of stupidity." --Edwin H. Land