All the pet hamsters in the world derive from a small wild population collected in Syria in the 1930s. Martha Foley and Curt Stager talk about hamsters, in the wild and working the wheel.

Martha Foley and Dr. Curt Stager discuss Betsey Dexter Dyer's book, A Field Guide to Bacteria, and the distinctive traits of individual bacteria that are visible to the naked eye.

"Old as the hills" is a relative term. The Adirondacks may be relatively young mountains, but their distinctive grey granite, anorthosite, originated 1.1 billion ago, so deep in the earth's crust that only continental collision could have formed it.Dr. Curt Stager and Martha Foley discuss Adirondack geology.

Watching whirligig water beetles, found in circling clumps on the surface of calm fresh water, is a favorite childhood activity of many, including one-time child Martha Foley. Dr. Curt Stager explains the method behind their madcap collective behavior.

Diatoms are fascinating creatures that share some qualities of both plant and animal. Dr. Curt Satger and Martha Foley talk about these water-borne oddities that inhabit the base of the food chain in geometric "glass houses" of their own construction.

The barred owl is often heard but seldom seen. Dr. Curt Stager and Martha Foley discuss the habits of this nocturnal hunter, and Curt demonstrates his own highly-regarded version of its distinctive call.

The first warm, rainy night of spring is the best time to spot this amphibian, while they migrate to forest pools for mating. Martha Foley and Dr. Curt Stager discuss this northern forest native and its curious boreal nuptials.

A common (if unwelcome) sight on trees in the apple and cherry family is the nest of the tent caterpillar, whose voracious appetite can completely strip a tree of foliage. These moth larvae are unusual, both in their engineering feats and their social organization.

A common (if unwelcome) sight on trees in the apple and cherry family is the nest of the tent caterpillar, whose voracious appetite can completely strip a tree of foliage. These moth larvae are unusual, both in their engineering feats and their social organization.

Some people claim immunity from tickling, and no one seems to be able to tickle themselves. The ribs, underarms and feet are the most effective tickle targets. Dr. Curt Stager and Martha Foley continue their discussion with the anatomy of tickling.