Still working on my review of Science and Human Origins (yes, I have been somewhat lazy when it comes to blogging) in the meantime enjoy the following items.
The title of this post are two common remarks one hears when the press covers evolution. Drives me straight up the wall. A study published in the Proceedings of the Royal Society B looks at these claims from the standpoint of paleontology and paleoanthropology.
On my view of descent with modification, the origin of rudimentary organs is simple. We have plenty of cases of rudimentary organs in our domestic productions,—as the stump of a tail in tailless breeds,—the vestige of an ear in earless breeds,—the reappearance of minute dangling horns in hornless breeds of cattle, more especially, according to Youatt, in young animals,—and the state of the whole flower in the cauliflower. We often see rudiments of various parts in monsters. But I doubt whether any of these cases throw light on the origin of rudimentary organs in a state of nature, further than by showing that rudiments can be produced; for I doubt whether species under nature ever undergo abrupt changes. I believe that disuse has been the main agency; that it has led in successive generations to the gradual reduction of various organs, until they have become rudimentary,—as in the case of the eyes of animals inhabiting dark caverns, and of the wings of birds inhabiting oceanic islands, which have seldom been forced to take flight, and have ultimately lost the power of flying. Again, an organ useful under certain conditions, might become injurious under others, as with the wings of beetles living on small and exposed islands; and in this case natural selection would continue slowly to reduce the organ, until it was rendered harmless and rudimentary.
Any change in function, which can be effected by insensibly small steps, is within the power of natural selection; so that an organ rendered, during changed habits of life, useless or injurious for one purpose, might easily be modified and used for another purpose. Or an organ might be retained for one alone of its former functions. An organ, when rendered useless, may well be variable, for its variations cannot be checked by natural selection. – Charles Darwin, On the Origin of Species
Science Daily mentions an interesting paper on Core Nuclear Pore Elements Likely Shared By All Eukaryotes:
But, it doesn’t link Great Whites and Megalodon. Longtime readers may remember this three part series on the subject. An interesting new fossil has been discovered that sheds some more light on the subject.