Some Mathematical Studies. in Genetics

This ratio is called Mattiessen's ratio. Nilsson and Pelger's computer model homed in unerringly on Mattiessen's ratio. And so to the question of how long all this evolutionary change might have taken. In order to answer this, Nilsson and Pelger had to make some assumptions about genetics in natural populations. They needed to feed their model plausible values of quantities such as БЂњheritability.БЂ«Heritability is a measure of how far variation is governed by heredity. The favored way of measuring it is to see how much monozygotic (that is, БЂњidenticalБЂ«) twins resemble each other compared with ordinary twins. One study found the heritability of leg {82} length in male humans to be 77 percent. A heritability of 100 percent would mean that you could measure one identical twin's leg to obtain perfect knowledge of the other twin's leg length, even if the twins were reared apart. A heritability of 0 percent would mean that the legs of monozygotic twins are no more similar to each other than to the legs of random members of a specified population in a given environment ...»