You can't see the Sun's ultraviolet rays with your eyes—you just see their results on your freckled, tanned, or sunburned skin. Build a bracelet that immediately detects these invisible rays.
When does mixing every color under the rainbow create pure white rather than a murky brown or black? When light, not paint, is the medium—and you're subtracting, not adding, color.
Are those sharp, pointy dinosaur teeth all the better to eat you with? Or are they designed for tough vegetation? Examine dinosaur teeth as a paleontologist would.
It probably comes as no surprise that telescopes do a better job of collecting light and observing outer space than your eyes. But do you know why? (Hint: the answer is NOT magnification!)
Living on land as we do, it's easy to forget this is a water planet. Yet life appeared about 3.5 billion years ago in the ocean, and instead of leaving, most things stayed there.
When in comes to breathing under water, marine organisms breathe in different ways. Some absorb oxygen through their skin, some rely on gills, and others gulp air into their gas bladders.
Classroom Activity, Hands-on Activity
Natural selection plays a large role in the evolution of a species. The following activity demonstrates this concept.
It's not what they ate or when they lived that distinguishes dinosaurs from other reptiles. It's the hole in their hip socket. Find out how this feature affected the way dinosaurs walk.
Can you walk like a dinosaur? Hint: The movement is not like lizards, crocodiles, and other reptiles; instead, it's more like birds. Investigate what else birds and dinosaurs have in common.
What kind of fossil is a tooth—body or trace? How about a nest of eggs? Or a skin impression? Examine the differences between body and trace fossils with these eight high-quality photographs.