A more cynical soul than Cate Gable once said that the chicken crossed the road to show the possum that it could be done. But jokes aside, road kill is never funny, even for non-native animals. Ms. Gable's "Coast Chronicle" wrought a thoughtful meditation on biodiversity from the sad spectacle of a mother possum and its young killed on the highway: well done.
However, Cate, may I suggest that you seek a sounder source for your biological fact-checking than your friend - Google would do nicely, the library even better. Yes, possum mammaries are teats, and possums are of course mammals. To say that marsupials are not mammals is akin to saying that hawks or penguins are not birds.
Marsupials are mostly confined to Australia, but the opossum, or possum,is native to North America. It was introduced to the West Coast in the 1940s. Of the three infraclasses of mammals, one includes the egg-laying echidna and platypus; another, the pouched marsupials; and the third comprises the placental mammals, which are all the rest. Possums belong to one of several orders of marsupials.
Other orders of mammals include, for example, rodents, carnivores, and primates. Being vertebrates, if possums were not mammals, they would have to be fish, reptiles, amphibians, or birds - in which case, they probably wouldn't get hit so often.
Finally, you write that "I was either a mammal in another life ...or simply have an extra dose of 'biophilia.'" I very much hope you are a mammal in this life, Cate. Since your columns show that you definitely have backbone, your only other choices, as with possums, would be fish, reptile, amphibian, or bird. I don't picture you as any of these.
Biophilia is a fine thing, and we earnestly hope for greater display of it among our more callous neighbors. But I worry more about the people's lack of ordinary natural history awareness. If we forget that we humans are mammals too, just like possums, sea lions, bats, and orcas, then surely all is lost.
ROBERT M. PYLE