Q. In a math competition between babies and birds, who wins? Could a 5-month-old infant outfigure a crow?

A. It's known that crows in a field with a watchshed nearby are able to keep track of how many watchmen are inside: When one person goes in, the crows know to keep their distance. When the person comes back out, the crows return to the field.

But what if two people go in and only one comes back out? Crows are no bird brains: They know two minus one leaves one still in the shed. And if three watchmen go in but only one or two exit; or if one goes in, then another, then one of the two comes back out, this still won't fool the birds. Not until the number of watchmen reaches five or six will the crows lose count.

Can babies do as well? Enter Karen Lynn and her "looking time" experiments, based on the premise that an infant will look a little longer than normal at something that seems wrong or perplexing.

Test #1: Show Baby a doll, then put it behind a screen, then remove the screen. Result: Baby sees one doll as expected and gives it only a brief look.

Test #2: Put one doll behind the screen, then another, then unveil two dolls. Result: Still OK by Baby.

Test #3: Place one doll, then a second, then show only one doll (the other was removed through a trap door). Result: Not OK by Baby - a longer stare.

As it turns out, both simple addition and subtraction are within Baby's ken, but numbers beyond two or three probably overtax visual capacity. So at this stage of the math race, the crows lead by a beak.

Q. When throwing up, have you ever felt like croaking?

A. Frogs and toads certainly must, if you can believe what they go through: After ingesting toxins from an ant or wasp, a frog disgorges its entire stomach, which hangs outside by a couple of membranes.

Now the frog cleans the organ with a "hand" - always the right hand, probably due to the position the stomach winds up in - then stuffs it back in.

Q. When hypnotism is used as anesthetic during a medical procedure, where does the pain go?

A. When hypnotized volunteers were asked to put an arm into a bucket of icy water that would ordinarily feel painful, many said they felt little pain. But asked if "some part of them" was feeling the pain, they said "yes."

So what was going on here? Was the pain in some sense really diminished or was it still there but "roped off" into a part of consciousness that could somehow be ignored? There is no definitive answer, say John M. Darley et al in "Psychology." But hypnosis clearly works, ranking in some situations ahead of morphine and acupuncture as a pain killer.

Q. How is sleep like love and happiness?

A. If pursued too ardently, sleep too will elude you, says psychologist Wilse Webb. One experimenter invited volunteers to spend two consecutive nights in a sleep lab, and on the second night offered them $10 for every minute they fell asleep faster than the night before.

Nobody collected.