Meet the rat-sized common ancestor of mammals

It lived 66 million years ago, and it might be your ancestor:

Humankind’s common ancestor with other mammals may have been a roughly rat-size animal that weighed no more than a half a pound, had a long furry tail and lived on insects. In a comprehensive six-year study of the mammalian family tree, scientists have identified and reconstructed what they say is the most likely common ancestor of the many species on the most abundant and diverse branch of that tree — the branch of creatures that nourish their young in utero through a placenta. The work appears to support the view that in the global extinctions some 66 million years ago, all non-avian dinosaurs had to die for mammals to flourish.

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Modules and evolution

In "The Parts of Life," Karl Zimmer takes a close look at evolving computer networks and concludes that modules and minimal connections facility efficient evolution.

[A]s networks become more efficient, they become more modular. But once the parts of a system emerge, natural selection may then favor modules themselves, because they make living things more flexible in their evolution. Once life’s Legos get produced, in other words, evolution can start to play.

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The liberal war on science

At Scientific American, Michael Shermer points out that not all of those who are obtuse about science are conservatives. Many liberals hold views that conflict with basic science:

41 percent of Democrats are young Earth creationists, and 19 percent doubt that Earth is getting warmer. These numbers do not exactly bolster the common belief that liberals are the people of the science book. In addition, consider “cognitive creationists”—whom I define as those who accept the theory of evolution for the human body but not the brain. As Harvard University psychologist Steven Pinker documents in his 2002 book The Blank Slate (Viking), belief in the mind as a tabula rasa shaped almost entirely by culture has been mostly the mantra of liberal intellectuals, who in the 1980s and 1990s led an all-out assault against evolutionary psychology via such Orwellian-named far-left groups as Science for the People, for proffering the now uncontroversial idea that human thought and behavior are at least partially the result of our evolutionary past.

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