Q. When we studied high school biology, our teacher said more than 99 percent of animals lay eggs and only a few give live birth. That percentage seems too high. Humans, dogs, cats and cows are ...

Should men trying to have kids avoid hot tubs? Do boxers vs. briefs impact sperm counts? Here's the real science behind male fertility.

A tree frog: female (larger individual below) laying eggs, which are protected by the 'foam nest' and male (smaller individual above). When it comes to laying eggs, tree frogs have some unusual habits ...