Over the past 35 years, scientists have made several curious discoveries about Huntington’s disease. First, individuals with the neurological disorder are less likely than others to suffer from cancer; second, they tend to have more children than average—about 1.24 children for every one child born to unaffected siblings. Although no one yet knows what is behind these seemingly unconnected find...

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Evolutionary models of cultural change have acquired an important role in attempts to explain the course of human evolution, especially our specialization in knowledge-gathering and intelligent control of environments. In both biological and cultural change, different patterns of explanation become relevant at different 'grains' of analysis and in contexts associated with different explanatory ...

also there was a tendency to borrow heavily from the evolutionary theories of Herbert Spencer and Charles Darwin (‘survival of the fittest’ is a vulgarisation of a more complex theory); especially, they drew on the idea of struggle and survival as the natural mechanisms for maintaining and improving the ‘stock’—i.e., genetic characteristics—of human beings. This was the origins of so-called ‘sc...