Ed Brayton, for example, seems to think it a highly damning critique to lampoon O'Donnell's remarks on certain sexual practices by pointing to the animal kingdom, where those same sexual practices occur, as if the reader is supposed to conclude that this is somehow morally instructive for humans.
I have dealt with this whole line of argument before in "Gay Penguins and the Inductive Argument from Hell": that if we can find animals that do something, we must therefore conclude it's okay for humans. Start down that road and it's interesting what you end up committing yourself to.
Here are ten animals we do not want to emulate:
- Komodo dragons, polar bears, crocodiles, etc. (eat their young)
- Fishing spiders (eat potential mates)
- Bachelor biting midge, female redback spider (eats opposite sex after mating)
- Spotted hyena, seabirds (murders siblings)
- Ichneumon wasp (tortures others insects)
- Hippopotamus (attracts mate by urinating & defecating)
I would also mention the female giant green anaconda, which mates with multiple males at one time, but you never can be sure what interesting inference from their own reasoning these people may already accepted. So why bother. These are people who are pretty far gone, morally speaking, so its getting harder and harder to find something that's outrageous according to their morality (and I use that term loosely)
By the way, why is it always some debased behavior we're supposed to mimic in nature? When was the last time you heard these people pigeons who mate for life, or dogs for their loyalty or bees for their industriousness and arguing that we should emulate them. Why is vice, rather than virtue, the only thing we can learn from nature?