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Natural Selections: The Treeline

Thu, Nov 19 Listen

Martha Foley and Dr. Curt Stager talk about the timberline, the usually abrupt termination of forest growth above a certain altitude. While it results from a combination of unfavorable factors, the final straw seems to be the length of time free of hard frost. When the growing season is too short to overcome damage from the harsh climate, the trees die out.

Natural Selections: One small change can greatly affect an ecosystem

Thu, Nov 12 Listen

Why do ponds with fish have more plants around them? When just one small part of an ecosystem is changed, everything is affected. Dr. Curt Stager and Martha Foley discuss some examples.

Natural Selections: Northern Shrike

Fri, Nov 6 Listen

Sometimes the bird at your feeder is looking to feed on other birds. Dr. Curt Stager tells Martha Foley about a recent rare visitor outside his window, the northern shrike.

Natural Selections: Camel Spiders

Fri, Oct 30 Listen

Like Martha Foley, you, too, may have seen a picture of this spider in your e-mail inbox. Is it real, or an imaginary creature come-to-life on the computer? Dr. Curt Stager gets the facts.

Natural Selections: Burl wood

Thu, Oct 22 Listen

Burl wood, the knobs of complex grain that some trees form, is prized by woodworkers for its beauty and utility. What causes wood grain to deviate from the straight and narrow in this way is something of a mystery. Martha Foley and Curt Stager try to untangle the knot.

Natural Selections: Whale anatomy

Thu, Oct 15 Listen

From the bones of their fins to the free-floating and functionless pelvis, the bodies of cetaceans show clear signs of having once lived on land. Why go back to the sea? Dr Curt Stager and Martha Foley examine the tale of the whale.

Natural Selections: Tree growth

Thu, Oct 8 Listen

Trees may live for hundreds, thousands of years, but there are limits on their growth. Trees can only move so much water, and only to a certain height. Martha Foley and Dr. Curt Stager discuss the hydrology of trees.

Natural Selections: Buckwheat

Thu, Oct 1 Listen

Although we use buckwheat flour for many of the same purposes as wheat flour, the plants they originate from are not even closely related. And thats a good thing for those suffering gluten allergies. Martha Foley and Dr. Curt Stager on kitchen science.

Natural Selections: Hover Flies

Thu, Sep 24 Listen

A common invasive species, the hover fly, or drone fly, looks remarkably like a honeybee. But in its youth, it carries the loathsome monicker, the rat-tailed maggot. Martha Foley and Dr. Curt Stager discuss Batesian mimicry?innocuous creatures who imitate more dangerous species.

Natural Selections: Adirondack Anorthosite

Thu, Sep 17 Listen

Anorthosite, the signature grey rock familiar to climbers and hikers in the Adirondacks is an ancient form of granite formed 15 miles below the surface more than a billion years ago. Pushed to the surface by recent mountain building activity, its deep cracks form the valleys and deep lakes of the region. Martha Foley and Curt Stager talk about the areas "ancient bones."

Natural Selections: Red-backed Salamanders

Thu, Sep 10 Listen

This northern forest species is so common that its biomass would outweigh all the large mammals and birds in its habitat combined. Martha Foley and Dr. Curt Stager look at forest amphibians.

Natural Selections: Guppies, Bright and Drab

Thu, Sep 3 Listen

If male guppies use bright colors to attract mates, why are there still lots of drab guppies? Bright colors may attract the attention of more than just potential mates. Dr. Curt Stager and Martha Foley discuss the upside and downside of male flash.

Natural Selections: Fallout and carbon dating

Thu, Aug 27 Listen

Curt Stager and Martha Foley discuss radiocarbon dating. Fallout from atmospheric testing of nuclear weapons has distorted the background levels of the radioactive isotope carbon-14, used by archaeologists to date organic materials. But it has an upside, providing a new scale by which to date more recent events, helping researchers track cell turnover in different parts of the body, and in testing the age of everything from vintage wine to elephant ivory.

Natural Selections: Pitcher Plants

Thu, Aug 20 Listen

Most carnivorous plants, such as the pitcher plant commonly found in Adirondack bogs, live in poor soils. Unwary insects are drawn to a sweet bait to supplement their diet. Curt Stager and Martha Foley discuss these botanical oddballs, which may live as long as fifty years.

Natural Selections: Hamsters

Thu, Aug 13 Listen

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.

Natural Selections: stellar distances

Mon, Aug 10 Listen

Martha Foley and Dr. Curt Stager talk about stars and the very clever ways we can tell their distance from the earth.

Natural Selections: Black squirrels

Thu, Jul 30 Listen

Black squirrels are becoming more common throughout the St. Lawrence Valley. They are a normal variation of the more familiar gray squirrel species. Martha Foley and Dr. Curt Stager discuss melanism, an increase in the pigmentation of some species that can be a response to environmental factors.

Natural Selections: Emerald Ash Borer

Fri, Jul 24 Listen

Martha Foley and Dr. Curt Stager talk about the Emerald Ash Borer, the insect behind those purple traps were seeing hanging from trees all over the North Country.

Natural Selections: the Pleaides

Thu, Jul 16 Listen

The Greeks called them "The Seven Sisters," but a look at the Subaru logo shows the Japanese saw them differently. This familiar star cluster constellation actually contains thousands of stars when viewed through a telescope, as well as brown dwarf proto-stars and dust nebulae and newly-forming solar systems. Martha Foley and Curt Stager look at the night sky.

Natural Selections: Turtle anatomy

Thu, Jul 9 Listen

Turtles breathe backwards; that is, when they relax their diaphragms, they inhale rather than exhale. Martha Foley and Curt Stager discuss the oddities of anatomy that arise from living in armor.

Natural Selections: Turtle Crossing

Thu, Jul 2 Listen

For turtles, crossing the road is a common danger, and it can also be one for the good Samaritan who tries to shepherd a snapper through traffic. Martha Foley and Curt Stager share safe technique, and try to answer the immemorial question, "Why did the turtle cross the road?"

Natural Selections: Wintergreen Oil

Thu, Jun 25 Listen

Wintergreen oil is best known for its fresh minty flavor, but it also has a long history as an effective herbal painkiller. Dr. Curt Stager and Martha Foley talk about this home remedy which, like its chemical cousin aspirin, can be hard on the stomach, and is toxic in high doses or with prolonged use.

Natural Selections: Extreme bacteria

Thu, Jun 18 Listen

Some bacteria like it hot, geyser hot, and some like it cold, refrigerator cold. Dr. Curt Stager and Martha Foley look at bacteria that thrive in extreme environments.

Natural Selections: Plant blood

Thu, Jun 11 Listen

Do plants have blood? How does the human circulatory system compare to that of plants and trees? Martha Foley and Dr. Curt Stager tackle the question.

Natural Selections: Adirondack Trout, pt. 1

Thu, Jun 4 Listen

Martha Foley and Dr. Curt Stager talk about trout biology and habitat in the Adirondacks.

Natural Selections: Exploring cave life

Thu, May 28 Listen

Curt Stager and Martha Foley do some imaginary spelunking and talk about the peculiar variations of animal life in caves.

Natural Selections: Foxes

Thu, May 21 Listen

Join Dr. Curt Stager and Martha Foley for a discussion about foxes?their homes, their diets and other fox facts.

Natural Selections: American robins

Thu, May 14 Listen

Martha Foley and Dr. Curt Stager discuss the varieties and habits of American robins. There are half a dozen different kinds, including albinos. How do they arrive so early in the spring? Sometimes its because they never leave.

Natural Selections: Leaf Cutter Ants

Thu, May 7 Listen

Why do Leaf Cutter Ants cut leaves? Nesting material, food? As Martha Foley and Curt Stager explain, these ants are composting. What they actually eat grows on rotting leaves.

Natural Selections: Tent Caterpillars

Thu, Apr 30 Listen

Dr. Curt Stager and Martha Foley take a look at the voracious caterpillars that make their homes in silky "tent" structures in trees.

Natural Selections podcast (Environment)