Channel image: Natural Selections

Natural Selections

Conversations about the natural world with Dr. Curt Stager and Martha Foley, from member-supported North Country Public RadioMore from Natural Selections »

Most Recent Episodes

How do electric eels use their "juice"?

Aside from their properties as biological dynamos, electric eels have other peculiarities—they are not true eels, but are a kind of fish—and a kind of fish that needs to breathe air. The South American predator of river bottoms can reach 40 pounds in size and deliver a fatal shock to humans.They use electricity for a number of purposes other than shocking their prey, as a navigation aid, to communicate with others of its kind and to detect unmoving prey by making its muscles twitch.Martha Foley and Curt Stager discuss the life cycle of a shocking species.

Listen5:00

Loading…

Closet nemesis: the clothes moth

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.Martha has a personal beef with the moth and talks with Curt Stager about the life cycle of the moth, and how to fight its ruinous effects.

Listen

Loading…

Bats can sing, too!

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.

Listen

Loading…

Are porcupine quills like hairs or like feathers?

Porcupine quills are hollow, like feathers, and are made from the same material, but then so are hairs, and fingernails, and claws and scales. The quill is a unique adaptation of one of nature's commonest substances and it varies even among porcupines.African porcupines can weigh as much as 60 pounds and have quills as thick as soda straws. Martha Foley and Dr. Curt Stager talk about "prickly" matters.

Listen

Loading…

Why does the moon look bigger when it's on the horizon?

Why does the moon look bigger when it's on the horizon, than it does when it is high in the sky? Curt Stager shoots down all of Martha Foley's theories.There are a couple ways it could be a trick of the mind, but why then doesn't it work all the time? After physics, optics, geometry and psychology, what are you left with? "Wow, big moon."

Listen

Loading…