Epochs Underfoot

i-cb7243ea8b816289078bac7a48adb376-fossilbuzz.jpgFossils offer a rare glimpse into the past, as lifeforms we could scarcely imagine are preserved long after their day in the sun. But fossilization requires very specific conditions, and few things that die are turned to stone. On Living the Scientific Life, GrrlScientist presents Haplocheirus, a theropod with “three toes, a birdlike keel-shaped chest and a long beak,” but also “small teeth, like a dinosaur.” This creature bolsters the idea that birds evolved from dinosaurs through independent lines. On Not Exactly Rocket Science, Ed Yong discusses fossilized dinosaur fuzz, which contains “the distinctive signs of melanosomes, small structures that are partly responsible for the colours of modern bird feathers.” Not only does this discovery strengthen the bird-dinosaur link, it also means we can fill in our Jurassic coloring books with a little more authority. And on Highly Allochthonous, Anne Jefferson describes the “verdant forests” of the Eocene epoch, which prospered in now-desolate polar regions when the Earth was a few degrees warmer. Canadian authorities may soon allow mining of “coal beds in one of the most spectacular of all the fossil localities in the High Arctic,” which Anne encourages us to oppose. When we dig up something new, it can change our understanding of everything.

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Cause and Effect

i-ef376aa01674d7e92fdfcf87b80dc9b3-causebuzz.jpgEvolutionary change responds to all kinds of pressures, and sometimes, the results can be surprising. On Gene Expression, Razib Khan challenges the idea that human evolution has stopped since “the vast majority of humans reach the age of potential reproduction.” He explains that differential mortality is not a precondition for natural selection, and supports his claim with data on human height and reproduction. In a separate post, Razib considers the feral dogs of Moscow, a pack of 35,000 with unique characteristics, such as the savvy to ride the subway. On Living the Scientific Life, GrrlScientist asks why some birds suffer the “tremendous sacrifices demanded by migration,” when suitable nesting ground is often closer at claw. New research suggests these birds may brave the inhospitable latitudes precisely because these harsh climes are less likely to support ravenous predators. And on Guilty Planet, Jennifer Jacquet wonders if Somali piracy has improved the catch by discouraging commercial fishing, a phenomenon which was previously witnessed after WWII. While wars and piracy may have unexpected upshots, Jennifer writes that if we just “left the ocean alone, fisheries would likely rebound.”

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Under Seas New and Old

i-c9274ffd863f87f18b0e4ae4f14fba75-seabuzz.jpgDarren Naish inspects “trace fossils” on Tetrapod Zoology, geologic records of footprints and other indentations left behind by animals. Although these telltale signs can “provide excellent information on behaviour and lifestyle,” it can sometimes be hard to tell what kind of creature made them in the first place. Such is the case with a set of mysterious parallel grooves preserved in a Jurassic sandbar, which may have been formed by the snouts of ancient sea monsters trolling for snacks. On Laelaps, Brian Switek reconsiders unilinear assumptions of cetacean evolution, citing “a particularly rich fossil site” in Pakistan which has revealed a broad diversity of early whale species. And on Neurotopia, Scicurious outlines the sexual proclivities of diatoms, prolific photosynthesizers which often reproduce asexually but were recently caught doing it with each other by the millions. Finally, visit Eric Klemetti for an incredible video of an underwater volcano spewing ire on Eruptions.

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Living This Way

i-0e04765eca436db089c33d7650d20208-natbuzz.jpgWhen it comes to human nature, everyone’s an expert—so let’s argue about it, shall we? On Cognitive Daily, Dave Munger reviews an investigation into the truly fairer sex which suggests that “men are more tolerant of their friends’ failings than women.” Not convinced? Then counter your intuition on The Frontal Cortex, where Jonah Lehrer writes “nothing destroys a luxury brand like a sale.” Consider the possibility of pulling yourself up by the bootstraps on Laelaps, where Brain Switek discusses Louis Leakey’s “fuzzy” postulation that “the invention of stone tools allowed humans to domesticate themselves and accelerate evolution.” Go on and question the innateness of Good and Evil with Razib Khan on Gene Expression, in light of the finding that eighteen-month-olds don’t hesitate to lend strangers a helping hand. Finally, if you missed it, see David Sloan Wilson’s fascinating series about group selection on Evolution for Everyone, where he speculates that our ancestors used their rock-throwing prowess to “suppress bullying and other domineering behaviors within-groups.” Now write up some comments and let us know where we got it all wrong.

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Happy Birthday, Origin!

i-37e9a7ef499187063d96ca72d2409312-originbuzz.jpgCharles Darwin’s Origin of Species was published 150 years ago today, and it continues to inform, illuminate, and stir up controversy. Of course, some tortoises live longer than that, but Darwin’s lasting legacy seems assured. On Gene Expression, Razib Khan tackles a study on the Fore, a cannibalistic people who ate their dead up until 1960. This diet left an imprint on their genes: a deadly prion-caused illness called Kuru led to selection against homozygosity in key alleles. Elsewhere, ERV explores invasive species and their fitness versus native species when both are infected with the same pathogen. In the case of Northern California grasses, although the native perennials are more fit than the invasive annuals, the pathogen hits the natives harder, and so the invaders become more successful. Finally, James Hrynyshyn on The Island of Doubt reviews a new coffee-table book on Darwin that “tells us at least as much about Darwin the man as it does his revolutionary idea.” Get one now, as Hrynyshyn suggests oversize books may be a dying species.

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The Great Debate

i-4daf3576fe3d9c6441642c5541cb6f8a-idbuzz.jpgThe pitched battle between evolutionary theory and Intelligent Design has become one of the signature conflicts of the decade. On Pharyngula, PZ Myers picks up the pieces after his debate with Jerry Bergman on whether ID should be taught in schools. Unambiguously he writes, “creationists are not the heralds of a coming paradigm shift; they are the rotting detritus of the old regime of unreason.” Elsewhere, on Gene Expression, Razib Khan crunches some numbers which show that 10-20% of people in certain Muslim countries believe in evolution, versus 80% in certain European countries. The support for evolution in the U.S.? 40%. Finally, on The Primate Diaries, Eric Michael Johnson parses centuries of anthropocentric thought which placed man atop the “great chain of being,” with other forms of life transitioning smoothly into the inanimate. As Johnson writes, “this vision of divinely ordered perfection was dramatically ripped apart, link-by-link, on November 24, 1859,” a date we will observe next week on the sesquicentennial of Darwin’s Origin of Species.

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New Twists on the Double Helix

i-f8154d0a659650961de81dff61d67948-helixbuzz.jpgForget fashion; when it comes to expressing yourself, it’s your genes that wear you! On Not Exactly Rocket Science, Ed Yong discusses the explosive evolution of AEM genes in humans and elephants—two long-lived, social animals with “very, very large brains.” Big brains need more juice to function, and AEM genes, which govern how mitochondria metabolize food energy, may be a key to evolving intelligence. On Gene Expression, Razib Khan explores the links between gene transmission and language transmission, writing that “linguistic affinity” could modulate gene flow, and vice versa. On Mike the Mad Biologist, Mike flays proponents of “genetic conservatism,” who believe that IQ is highly heritable and educating everyone is a waste of money. This attitude leads Mike to wonder, “What is the genetic heritability of being an ***hole?” Finally, Daniel MacArthur on Genetic Future reports the bankruptcy of deCODE Genetics and the revamped product lineup at 23andMe, suggesting that personal genomics may need a new business model.

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