Are elephants the only source of ivory? No. Ivory comes from many other animals, besides elephants. It is also possible to make synthetic ivory. Ivory is a hard, white substance that forms the teeth and tusks of a lot of animals. It is made of dentine, which is a form of bone. The inside of […]
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Why does walking become harder as we get older? It is a combination of age-related factors, such as stiff joints, brittle bones, lack of balance, deteriorating muscles, shortening ligaments, deteriorating nerves, and even neurological factors. As we age, our bodies start to deteriorate and that results in a changed way of walking. That is unavoidable,
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How can you tell if a planet has life? The light coming to us from the planet’s star would show signs of oxygen, water, or some other chemical that we associate with life. The first problem with trying to find life on other planets is that we tend to look for the signs that our
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Why do we die so quickly without water? Our bodies need water for so many processes and that means it needs a steady supply of water going in to balance the water going out. There is a saying that a human can go three minutes without oxygen, three days without water, and three weeks without
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Can we eat insects? Yes. In fact, not only can we eat insects, but we should eat insects. They are nutritious, easy to grow, and not bad for the environment. The average human needs between 1,600 calories to 3,000 calories, depending on our gender and our body size. Those calories need to be roughly 60%
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Why do salmon swim upstream? They return to the place they were born to lay their eggs. Salmon are born in freshwater streams. The adult salmon lay eggs in the sand and gravel at the bottom of the river, which hatch and become baby salmon, which are called alevins. The alevins still have a yolk
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What did the peppered moth do? It changed from a light color to a dark color during the Industrial Revolution. The peppered moth is native to most places in the northern hemisphere. They are about 5.5 cm with their wings spread out. They fly at night and they are generally a mix of light colors
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How many different eye colors do people have? There are only 6 different eye colors. They are amber, blue, brown, gray, green, and hazel. There are many different colored eyes in the animal kingdom, but humans are far more limited in eye color than we think. Out of the six colors, brown is the most
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What is DDT? It stands for dichloro-diphenyl-trichloroethane and was the first synthetic pesticide. It was banned in 1972. DDT didn’t start being used in large quantities until after the Second World War, but it had been discovered quite a while earlier. Othmar Zeidler, an Austrian chemist, first synthesized DDT in 1874. Nobody realized that it
How does a cheetah run so fast? It is a combination of their body weight, their claws, their spine, their joints, the type of muscles they have, their tail, their organs, and the size of their head and skeleton. Cheetahs are the fastest land animals. They have a top speed of approximately 113 km/h and
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