Cousin opossum:
There is more wildlife in our yard than there was when I was a child. There were a number of energetic dogs that kept anything but squirrels out of site. Our own dog once pursued an opossum into a fifty gallon drum in the garage, where it turned at bay. When we investigated the barking it was a simple matter of setting the drum up on end and we had captured the opossum. Then came the question of what the beast might be happy to eat. Table scraps seems rather obvious but in my excitement I ran inside to look the animal up in the encyclopedia. I could not find it under “p.” It now seems that usage has changed. Possum is an acceptable word.
If animals must mate with kin to survive, then it makes sense that they should be able readily to recognize kin. It turns out that the opossum can. (SNV Brother Can You Share a Hollow? SCIENCE vol. 331 no. 6019 February 18, 2011 page 823 reviewing Proc. R. Soc. London Ser. B 278, 10.1098/rsb.1020.2657 (2011)) These beasts tend to share their tree hollows with unrelated opossums except when times are hard and hollows are in short supply, when they prefer relatives.
So yes, they can tell relatives. And indeed they have continued to flourish while most species that need hollows have declined. “Modern forest management” means taking out the nice old trees. So the cousin thing has worked for opossums.
Hmm.
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