Conservation and restoration of fur objects made from keratin, which is also the protein that makes up skin, feathers, nails, hooves, claws, and horns. "The way I think a lot of people understand fur versus hair is in the density of follicles," says Ross McPhee, Curator of the Department of Mammalogy at the American Museum of Natural History. "So for fur-bearing animals—which were converted into coats and so-forth—people always wanted it to be something that was very dense, so there’s the idea therefore that fur is dense, and it certainly is in [the] kinds of fur-bearers that we use for this purpose. Whereas hair is not
Hair cell They have also improved frequency selectivity (frequency discrimination), which is of particular benefit for humans, because it enabled sophisticated speech and music. Outer hair cells are functional even after cellular stores of ATP are depleted. The effect of this system is to non-linearly amplify quiet sounds more than large ones so that a wide range of sound pressures can be reduced to a much smaller range of hair displacements. This property of amplification is called the cochlear amplifier. The molecular biology of hair cells has seen considerable progress in recent years, with the identification of the motor protein (prestin) that