Deep-ocean microbe is closest living relative of complex cells – “A new study indicates that plants, fungi, and animals are descendants of archaea, the group of single-celled organisms that includes Sulfolobus, a resident of hot springs.” – h/t bill barendse! – see also: New Loki Microbe Is Closest Relative To All Complex Life.
A Surprise for Evolution in Giant Tree of Life – “Researchers build the world’s largest evolutionary tree and conclude that species arise because of chance mutations — not natural selection…. This controversial proposal stems from efforts by Hedges and collaborators to build the world’s most comprehensive tree of life — a chart plotting the connections among 50,000 species of Earth’s vast menagerie. Their analysis suggests that speciation is essentially random. No matter what the life form — plant or animal, insect or mammal — it takes about 2 million years for a new species to form. Random genetic events, not natural selection, play the main role in speciation.” – see also Was Charles Darwin Wrong About Speciation? from razib.
Genetic changes to basic developmental processes evolve more frequently than thought – “Newly evolved genes can rapidly assume control over fundamental functions during early embryonic development. The findings suggest that evolutionary changes to the genetics of fundamental biological processes occur more frequently than previously thought.” – h/t david bachinsky!
The First GMO Is 8,000 Years Old – “Scientists find that bacteria modified DNA in sweet potatoes millennia ago.”
Behavioral idiosyncrasy reveals genetic control of phenotypic variability [pdf] – “If we could rear genetically identical individuals from a variety of genetic backgrounds and rear them in the same environment, how much phenotypic variation between individuals of the same genotype would we see? Would different genetic backgrounds differ in their degree of variability? What would account for these differences? We used Drosophila inbred lines to address these questions focusing on variability in locomotor handedness. We show that different genotypes vary dramatically in their propensity for variability, that phenotypic variability itself, as a trait, can be heritable, and that loci affecting variability can be mapped. The genetic control of variability has received little attention in quantitative genetics despite the important role variability plays in explaining phenotypic variation between individuals.”
two tweets from the Biology of Genomes meeting re. a presentation on mutation rates:
CH: mutation rate is ~1.2e-8, w/ ~2X higher in males. ~20% de novo mutations in sperm occur during development v being inherited #BOG15
— Mark Gerstein (@markgerstein) May 8, 2015
Harland: In cow (& us??), many de novos arise in early embryo, not gamete. Hallmarks: freq != 0.5 til kid; no m/paternal chrom. bias. #BoG15
— Nathan Pearson (@GenomeNathan) May 8, 2015
Team Characterizing DNA from Ancient Human with Recent Neanderthal Ancestry [registration req.] – see also Ancient DNA from an Upper Paleolithic European with recent Neanderthal ancestry – “the male sample, Oase 1, is 37-42K years old and comes from the Pestera cu Oase site in southwestern Romania. it’s estimated to harbor 5-11% of genome-wide Neanderthal ancestry, with as much as 50% on chromosome 12. the admixture is in relatively long stretches, which suggests that the mixture took place four to six generations before Oase 1 was alive.“ – @the eurogenes blog.
The archaeology, chronology and stratigraphy of Madjedbebe (Malakunanja II): A site in northern Australia with early occupation – “The stone artefacts and stratigraphic details support previous claims for human occupation 50–60 ka and show that human occupation during this time differed from later periods.” – h/t chris stringer!
Stone bracelet is oldest ever found in the world – “Dating back 40,000 years to the Denisovan species of early humans, new pictures show beauty and craftsmanship of prehistoric jewellery.” – denisovan jewelry!!
The Old Race – from greg cochran.
Ancient DNA Tells a New Human Story – “The study of ancient DNA has challenged this view. We now know that mass migrations occurred repeatedly, overwhelming natives while absorbing some of their genes…. Joseph Pickrell of Columbia University and David Reich of Harvard University argue that ‘major upheavals’ of human population have been ‘overwriting’ the genetic history of the past 50,000 years. The result, they say, is that ‘present-day inhabitants of many places in the world are rarely related in a simple manner to the more ancient peoples of the same region.'” – from matt ridley.
The time and place of European gene flow into Ashkenazi Jews – @the eurogenes blog.
Symbolic bones and interethnic violence in a frontier zone, northwest Mexico, ca. 500–900 C.E. – “Persistent interethnic violence has affected some global regions for centuries…. In the prehispanic Northern Frontier of Mesoamerica, approximately 500–900 C.E., people of different ethnic backgrounds struggled for standing in a shifting sociopolitical landscape. Evidence is consistent with long-term social violence….” – h/t gaetan burgio!
London Conference on Intelligence 2015 Keynote – from dr. james thompson.
Three hundred years of low non-paternity in a human population – “Here we use this approach to investigate 1273 conceptions over a period of 330 years in 23 families of the Afrikaner population in South Africa. We use haplotype frequency and diversity and coalescent simulations to show that the male population did not undergo a severe bottleneck and that paternity exclusion rates are high for this population. The rate of cuckoldry in this Western population was 0.9% (95% confidence interval 0.4–1.5%), and we argue that given the current data on historical populations we have to conclude that, at least for Western human populations, cuckoldry rate is probably in the range of 1%.” – h/t debbie kennett!
Genius and autism may share genetic link, study finds – “Child prodigies and their autistic family members may share a genetic link, according to findings published online for the April issue of Human Heredity.”
The glass is half full *and* half empty: A population-representative twin study testing if optimism and pessimism are distinct systems – “Here, we addressed these questions in a genetically informative sample of 852 pairs of twins. Distinct genetic influences on optimism and pessimism were found. Significant family-level environment effects also emerged, accounting for much of the negative relationship between optimism and pessimism, as well as a link to neuroticism. A general positive genetics factor exerted significant links among both personality and life-orientation traits. Both optimism bias and pessimism also showed genetic variance distinct from all effects of personality and from each other.” – h/t stuart ritchie!
The Mask of Sanity Revisited: Psychopathic Traits and Affective Mimicry – h/t claire lehmann! who tweeted: “People with psychopathy can produce highly convincing but fake expressions of feelings.”
Behaviorism and the revival of antiracism – from peter frost.
Heterogeneity of long-history migration explains cultural differences in reports of emotional expressivity and the functions of smiles – hmmmm. really? – see also: What your smile says about where you’re from – “If you come from a country of immigrants, you’re more likely to crack a friendly smile on the street. That’s the conclusion of a new study, which may explain why Americans beam more than their Chinese and Russian counterparts.”
Is reading to your kids “unfairly disadvantaging” others? – hahahahahaha! – h/t brian boutwell! who tweeted: “The nonsense that you can believe when you’re convinced that genes don’t matter.” – see also Is having a loving family an unfair advantage?
Peter Visscher: Genomics, Big Data, Medicine, and Complex Traits – @steve hsu’s.
How can our future Mars colonies be free of sexism and racism? – (>.<) #virtuesignalling – h/t ed west!
After Nearly Claiming His Life, Ebola Lurked in a Doctor’s Eye – “Before he contracted Ebola, Dr. Ian Crozier had two blue eyes. After he was told he was cured of the disease, his left eye turned green [temporarily].” – whoa.
The Medieval Roots of Our DIY Gun Culture – “Forget 3-D printers. The first garage gunsmiths date back to the late Middle Ages.”
When Baltimore Shook With Anger, Here’s What China Saw – “Online reaction revealed much about Chinese tension with an influx of African immigrants.” – h/t holtz!
No, there’s no “hate speech” exception to the First Amendment – duh. – from eugene volokh.
bonus: The migration of the eagle hunters – awesome!
(note: comments do not require an email. kazakh eagle hunter!)