Watch "Law & Order" for all the oh-so-obvious signs that that the killer is lying – eyes darting like crazy, shifting in the seat, sweat beads on the forehead.

Certain facial expressions also are a giveaway, though they may be harder to pick up, according to a new study from Dalhousie University in Halifax, Nova Scotia.

Researchers followed the case of Michael White, an Edmonton man convicted of killing his pregant wife - Canada's version of Scott Peterson. He initially generated a lot of public sympathy with his tearful pleas for help in finding his wife.

But in an analysis of White's T.V. appearances, frame by frame, researchers found traces of anger and disgust – so fleeting that many in the public never noticed.

Researchers went on to test subjects in the lab. They were showed images that elicit happiness (puppies frolicking), fear (open-mouthed rabid dog, a close-up to boot) and ewwws (a severed hand), and videotaped subjects' reactions.

The researchers' findings, published in Psychological Science, showed that happiness is easier to feign than fear or disgust. But none of their subjects were able to fake their feelings perfectly.

Researchers said certain facial muscles cannot be controlled, and that some muscles are not activated in the absence of genuine emotion.

The “risk-taker” personality has come up a lot this week as people try to wrap their heads around the Spitzer scandal.

What served the outgoing N.Y. governor well in his professional career clearly did little for his interpersonal relationships.

One psychology professor, Marvin Zuckerman of the University of Delaware, has indicated in an interview the happiest marriages are between non-Spitzer like people. Meaning, people who "have great tolerances for boredom" and won't be itching for a new partner.

He's developed a scale that measures people's need for thrills.

Sample True/False statements include:
•I sometimes do "crazy" things just for fun.
•I prefer friends who are excitingly unpredictable
•I like to explore a strange city or section of town by myself, even if it means getting lost.

How do you score? How does your partner?

Research from the University of Maine suggests that women are OK with their mates taking risks when they deem it necessary, but are not that into thrill-seekers.

For his study, "Neither Daredevils nor Wimps: Attitudes toward Physical Risk Takers as Mates," psych prof William Farthing surveyed UMaine undergraduate women to assess men's response to scenarios involving physical risk. He found that women are attracted to men who take risks for altruistic reasons (like saving somone's life) and less so to men who have non-heroic reasons (whitewater kayaking, for example.)

Do you avoid the snake exhibit at the zoo? Did you turn away from watching Snakes on a Plane...the trailer?

You may have wondered whether you were being irrational about snakes. (When's the last time you saw a live one, anyway?) Research from the University of Virginia, though, suggests that snake phobia became hardwired in humans thousands of years ago as a survival tool.

A study published in this month's Psychological Science found that its subjects – who included preschool children with no prior experiences with snakes – appear to have a natural ability to quickly detect a snake from other things.

In one experiment, subjects were asked to find the image of a snake on a computer screen cluttered with photos of eight flowers, frogs or caterpillars. Another experiment called on subjects to look for the non-threatening item among a screen full of snake photos.

In each scenario, snakes were ID'd faster, with children picking the reptiles out as rapidly as the adults, despite the difference in age and experiences.

Researchers say this backs evolutionary theories that humans who mastered survival skills were able to reproduce and pass their abilities on in the gene pool.

(A cartoon snake for the ophidiophobes out there)