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Following up his comments on the stunning half billion years of changelessness (stasis) demonstrated by the pterobranch, David Tyler now addresses the unchanging cricket, one of whose fossils was found from 100 million years ago: He comments on howthe fact that many life forms seem motionless in time is handled in the science literature:
It is of interest to note how living fossils are described. Sometimes, they are “some of evolution’s greatest survivors”, and the splay-footed cricket is “obviously doing something right”. The Economist reporter says that the insect illustrates the “first rule of natural selection”: “If it ain’t broke, don’t fix it.” LiveScience took a different view, making the point that the animal has been “stuck in time for the past 100 million years or so”. Evolutionary theory wins all ways: if the animals document stasis, then they are fit for their environment and the environment has not changed with time. If they document change, then natural selection is at work, acting on natural variations. Images of the modern cricket are here and here.The problem with evolutionary theory today is that it finds nothing significant to learn from these examples of stasis. “If it ain’t broke, don’t fix it” seems to exhaust their mental powers. However, there are a host of issues waiting to be explored: What do these organisms tell us about limits to variation? What can be learned about biological innovation? Can microevolution be extrapolated to macroevolution? Is it realistic to expect environments to show the same stasis as these animals and plants? Living fossils are not just quirky – they are telling us something significant about the biological world. More here.