Introducing Evolution: A Graphic Guide
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Introducing Evolution explores evolutionary theory from its origins to its reception across history and how it has been developed and refined. Drawing on the latest findings from genetics, ecology, and animal behavior, it unravels the central and often misunderstood concepts, notably natural selection and the selfish gene.
brains than other kinds of bat. But there are not many other species that seem to practise tit-for-tat. Since tit-for-tat is the most plausible basis for reciprocal altruism, it seems likely that reciprocal altruism is not widespread in nature. Most biological altruism, it seems, is due to kin selection, not reciprocity. The Peacock’s Tail The existence of altruism among animals was not the only problem that baffled the first evolutionary biologists. The peacock’s tail was another. What
organism, the mutations have to occur in the same family, one after the other. In a sexual species, however, beneficial mutations can end up in the same organism even if they first occur in different families. Sex enables different families to swap genes. Reproductive Isolation Sometimes, a sperm meets an egg but cannot fuse with it. When this happens, no offspring is conceived. The male whose sperm it was, and the female whose egg it was, do not become parents. When organisms from two
How the Mind Works, Steven Pinker focuses on pragmatic capacities such as vision and child-rearing… …the things we prize most highly, such as art, morality and creativity are relegated to a speculative final chapter. One of the few evolutionary psychologists to address the issue directly is Geoffrey Miller. Art and morality are not side-effects of adaptations designed for survival purposes, but adaptations shaped by sexual selection. In Miller’s view, all the most distinctively human
Simple, yet so Powerful Three Conditions Animal and Plant Copies A Tale of Butterflies A Change in Environment Multicoloured Butterflies Evolution by Natural Selection Darwin’s Dangerous idea The Argument from Design Animals and Artefacts Adaptations Another Explanation for Biological Design A Single Step Many Small Steps Start the Story Again Cumulative Selection What Good is Half a Wing? The Blind Watchmaker Occam’s Razor No Need for that Hypothesis Natural Selection
with the watch, he thinks carefully about what changes will make the watch better. Evolution is very different. As we have already seen, natural selection is not like a normal human watchmaker, but like a blind watchmaker. The mutations that appear from time to time in every species are completely random. Just because a mutation is beneficial does not make it more likely to occur. We saw this in the story of the butterflies. When the branches became grey because of pollution, the best colour