The gene manipulation procedure does appear to work in cells taken from the pulpy tissue of extracted wisdom teeth. Scientists in Japan working with wisdom teeth from three donors were able to create several stem cell lines. In the lab, many of the c...
But whats true for mammals isnt always true for the rest of the animal kingdom. The sex of baby birds is also determined by two different sex chromosomes, but in birds, its the male that has two of the same-shaped sex chromosomes and the female that...
Wisdom teeth can be a nuisance. They may have once served a purpose way back in human prehistorybut today many people simply get rid of them. According to one study, though, wisdom teeth may be more useful than we realize at least when it comes to st...
Okay, so why not do what Galileo did when he first demonstrated this fact? Use a ramp instead of a building. Start your bowling ball and your golf ball at the same spot on the ramp and let go at the same time. If our intuitive sense of this situation...
Another sexual difference among mammals that doesnt hold with other animals is size. In most mammals the male is larger than the female, but in most other animals where there are two distinct sexes, the female is the larger one. Today scientists defi...
Why not? You cry.Well,ask yourself this question: which one is easier to move in the first place? The golf ball. So it takes more force to move the bowling ball. And the bowling ball is also the one gravity pulls on more. See the connection? A more m...
Heres a physics classic. Suppose you drop a golf ball and a bowling ball from the Empire State Building. Which hits first? Answer? They hit at the same time. You could also have used a marble and a piano and a banana, or any two objects for which air...
Finally, it can sit down and cover all the bases. Many birds are able to control the amount of blood flow through their legs, which increases their ability to regulate temperature. The only danger comes in standing around on a cold day: with one foot...
Most birds you see standing on only one leg are doing an impressive balancing act while tucking the second leg into their feathers. This is much easier to recognize in large birds, such as flamingos, but the behavior itself is common to most birds. S...
You might wonder about the chemicals other function thoughto attract more pike. A minnows skin is most likely to be damaged in an attack from a relatively small pike. Larger pike simply swallow their minnows whole. Because of this, the alarm substanc...
Beneath the surface of a pond or stream its a fish-eat-fish world, and the tiny minnow is often lunch for larger fish such as pike. Youd think a tasty minnow would try to remain inconspicuous, but this isnt always the case. If a minnows skin is damag...
In theory, if a subject lies on an important question, his polygraph response will be different from the truthful responses to the neutral questions. Does this really work? Its true that a polygraph can measure emotional stress, and its also true tha...
In an ideal world, a lie detector machine would measure some involuntary response which everyone has when they lie, but not when they tell the truth. Unfortunately, there is no such response and, because of this, no such thing as a perfect lie detect...
The big culprit on faces, though, isnt dirt so much as an internally-produced substance called sebum that makes the skin cells shed inside the pores. These dead cells, unable to flake away, collect until they become an irritation to the pore. At this...
Heres a great story of someone using their noggin to figure out something about nature. For a long time people have been fascinated by comets passing by the earth. But nobody knew how far away they were. Aristotle, for example, figured that comets we...