For thousands of years, the Maya, in what is now Central America, have planted their fields with alternating rows of corn and beans. Together corn and beans provide all the protein needed for a human diet. But thats not the only reason this combinati...
To understand why a plant would grow such heavy thorns, we need to look back ten or fifteen thousand years to a time when mastodons, mammoths, ground sloths, tapirs, and peccaries browsed from trees and bushes all over North America. Unlike todays sm...
Extinct animals are gone for good, but living species can sometimes tell us about the food chains that existed long ago. Hawthorns are members of the rose family with thorns up to five inches long. Like the thorns of other roses, these long thorns ev...
Do flying fish really fly? Or do the y just kind of jump out of the water? Great question， and the answer is Yes. There are around sixty-four species of flying fish, and they really do fly. Well, actually, they glide. Right，but they glide like bi...
Then, in 1676, a Danish astronomer named Ole Roemer saw something interesting in the sky. He was watching the moons of Jupiter go around something fairly easy to see even with a primitive telescope. He started marking down the exact times when one mo...
How fast does light travel? What could you do to find out? One natural thing to try is to have someone send some light your way and see how long it takes to reach you. How about if you got a friend to shine a flashlight at you from a distant hill, ex...
Researchers wondered if corticosteroid variability was somehow related to life strategies. Would birds like the short lived great Tit, which lays twelve eggs at a time, have different hormone levels than the Spotted Ant bird which lays only two eggs...
In the race of life, some animals are hares, running at top speed, producing lots of young and dying quickly. Others are tortoises, maturing slowly, producing few offspring, and living a long time. There must be physiological mechanisms that regulate...
Food Allergy A true food allergy has little to do with digestion instead, its an immune system response. Your body treats the food like a foreign invader, and manufactures antibodies to fight it. Any contact with the foodeven touching it or kissing s...
In the 1890s a young scientist, named Felix Hoffman, was looking for a cure for his fathers terrible arthritis. Hoffman noticed that acetylsalicylic acid produced the benefits of the earlier drug without the side effects. In 1899, the new compound wa...
A skydivers body is in a delicate balance. Gravity tugs her downward with a constant, relentless force, while air resistance pushes her upward. The faster she falls, the more air resistance there is, so eventually these two forces cancel out. Then sh...
Why not? She has reached whats known as terminal velocity. This is when the upward push of air resistanceor the friction she experiences as she falls through the airis enough to exactly counterbalance the force of gravity. When she first jumped out o...
Why would you want to jump out of a perfectly good airplane? Well, you get to the ground much faster, and the trip down is a whole lot more interesting. Skydiving has become an increasingly popular sport, although most of us havent yet taken the plun...
Dehydration is big problem in all the se sports because you dont feel like youre losing water. If you run or lift weights, the sweat acts as a psychological reminder to drink, but as you climb out of a swimming pool, your first thought may not be of...
After a day of skiing, bicycling, or swimming, some people find they get headaches something like a hangover from drinking too much the night before. Even though exercise is healthy and excessive drinking is not, the headache in either case is your b...
