Description
Haldaneās rule applies to the vast majority of heterogametic organisms examined. These include both male heterogametic (XY or X0-type sex determination, such as found in mammals and Drosophila) and female heterogametic (ZW-type sex determination, such as found in birds and Lepidoptera) animals, and some dioecious plants such as Silene. It appears to be a general pattern associated with heterogamety.
Hybrid sterility and inviability increase reproductive isolation, which leads to speciation. The fact that evolution can produce such a similar pattern of isolation in a vast array of different organisms is striking. However, the actual mechanisms leading to this result in divergent taxa appear to vary. The basis by which the heterogametic sex becomes more susceptible to hybrid inferiority (sterility or inviability) has been a focus of theoretical and empirical explorations that have greatly enriched our understanding of sexual reproduction and speciation.
Read more about this topic: Haldane's Rule
Famous quotes containing the word description:
“Why does philosophy use concepts and why does faith use symbols if both try to express the same ultimate? The answer, of course, is that the relation to the ultimate is not the same in each case. The philosophical relation is in principle a detached description of the basic structure in which the ultimate manifests itself. The relation of faith is in principle an involved expression of concern about the meaning of the ultimate for the faithful.”
—Paul Tillich (18861965)
“The great object in life is Sensationto feel that we exist, even though in pain; it is this craving void which drives us to gaming, to battle, to travel, to intemperate but keenly felt pursuits of every description whose principal attraction is the agitation inseparable from their accomplishment.”
—George Gordon Noel Byron (17881824)
“As they are not seen on their way down the streams, it is thought by fishermen that they never return, but waste away and die, clinging to rocks and stumps of trees for an indefinite period; a tragic feature in the scenery of the river bottoms worthy to be remembered with Shakespeares description of the sea-floor.”
—Henry David Thoreau (18171862)