Albert B Fernandez's List: Science

• Svante Paabo
• Neanderthals
• can now study genomes that belonged to people who died 40,000 years ago
• tudy the shape of fossils to learn about how we evolve
• A million years ago, the fossil record contained evidence of human-like creatures in Europe, Asia, and Africa.
• Before the 1990s, scientists could only
• eading hypotheses for how those creatures became Homo sapiens came in two flavors. Some scientists argued that all the Old World hominins were a single species, with genes flowing from one population to another, and together they evolved into our species. Others argued that most hominin populations became extinct. A single population in Africa evolved into our species, and then later spread out across the Old World, replacing other species like Neanderthals in Europe.
• the very first Neanderthal discov
• ered in 1857
• The ancestors of humans and Neanderthals branch off from the ancestors of chimpanzees 5-7 million years ago, and then humans and Neanderthals branch off in the last few hundred thousand years. If hu
• concluded that humans and Neanderthals must have interbred after our species expanded from Africa, and that about 2.5% of the genomes of living non-Africans comes from Neanderthals.
• the scientists estimated that the interbreeding happened between 37,000 and 86,000 years ago
• DNA probably can’t last more than a few hundred thousand years before degrading beyond recognition
• about 800,000 years ago, the ancestors of Neanderthals and Denisovans diverged from our own ancestors. They expanded out of Africa, and the Neanderthals swept to the west into Europe and the Denisovans headed into East Asia. Paabo put the date of their split about 600,000 years ago. The exact ranges of Neanderthal and Denisovans remain fuzzy, but they definitely lived in Denisova at about the same time 50,000 years ago, given that both hominins left bones in the same cave.
• Humans expanded out of Africa around 100,000 years ago, Paabo proposed. (I’m not sure why he gave that age, instead of a more
• ecent on
• a “leaky
• eplacement” mode
• Some of our genes have mutations also found in Neanderthals and Denisovans, but not in chimpanzees
• They must have evolved into their current form between 5 million and 800,000 years ago.
• only 78 unique human mutations
• FoxP2
• Most mammals have a practically identical version of the protein, but ours has two different amino acid
• If Neanderthals could talk, it would be intriguing that they apparently couldn’t paint or make sculptures or do other kinds of abstract expressions that humans did. And if Neanderthal’s couldn’t talk, it would be intriguing that they already had a h
• uman versi
• on of FoxP2
• Scientists at MIT, working with Paabo, have put his mice into mazes to see how quickly they learn how to find food. Mice with human FoxP2 develop new habits faster than ones with the ordinary version of the gene.
• Paabo’s hypothesis is that a single mutation to FoxP2 rewired learning circuits in the brain of hominins over 800,000 years ago
• . Our ancestors were able to go from practice to expertise faster than earlier hominins.
• apiens almost surely left Africa around 100,000 years ago with some of the best evidence from the genetics paper b
• Alan Templeton which you reviewed (and I read thoroughly) a few years ago. Since then there is additional field data suggesting a possibly even earlier date for leaving at least East Africa (caves in South Africa along the sea coast
• eandertal engaged in art much
• we simply do not know whether or not H
• the evidence of H. sapiens doing so is rather sp
• arce before ~50 ky

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• A designer God cannot be used to explain organized complexity because any God capable of designing anything would have to be complex enough to demand the same kind of explanation in his own right.
• A designer God cannot be used to explain organized complexity because any God capable of designing anything would have to be complex enough to demand the same kind of explanation in his own right.

• major changes in our understanding of evolution over the past twenty years have gone virtually unnoticed
• major changes in our understanding of evolution over the past twenty years have gone virtually unnoticed