Natural Selections NCPR: North Country Public Radio

The pressure to keep billions of humans fed can have a transformative impact on amimal populations. Overharvesting that targets the largest animals can result in reduction of the average size of species, as seen in Caribbean conch snails. And sport-fishing pressure on large mouth bass can winnow out the most agressive in the gene pool, resulting in a "lazier," more passive remnant population.

Martha Foley and Curt Stager talk about the human factor in animal evolution.

Keratin, the substance wool, hair, and feathers are made from, makes a pretty thin diet, but the clothes moth has been dogging humanity's closets and drawers for hundreds of years, unravelling the work of generations of knitters and weavers to feed its larvae.

Of all the places a cat can hang out, why do do many of them want to hang out in boxes? According to researchers, cats that spend time in close confines are measurably less stressed than those remaining in the open. As Curt Stager tells Martha Foley, it's not just house cats who feel this way.

Martha Foley has never succeeded in keeping a nature journal long-term, but Curt Stager finds them invaluable in his work. He records his observations on paper, but also finds great data through researching the journals of past observers, from Samuel de Champlain to Thomas Jefferson, to ordinary little-known North Country folk.

His hint - always put it on paper. Whatever became of all that stuff on your floppy diskettes?

Humans, birds, and whales are not the only creatures who can sing. Martha Foley and Dr. Curt Stager discuss recent research that uncovered bats also use learned songs to communicate.

We tend to think that dogs do this, and that cats do that. We think animal species have a recognizable set of behaviors that define the nature of their kind. But what about individual animals? Does each have something we could understand as a unique personality?