rfmcdonald: (Default)

  • Centauri Dreams notes new studies suggesting the flares of red dwarf stars damage potentially habitable planets.

  • The Crux notes that the wild apple is going extinct.
  • D-Brief notes that recent high winds in Europe helped push energy prices there to negative territory.

  • The Frailest Thing considers Neil Postman's thoughts on the intersection of mass media and childhood.

  • Inkfish argues in favour of accidental wetlands in urban areas.
  • Language Log looks at the trope of the repeated character in some recent Chinese advertising.

  • The LRB Blog considers the costs, environmental and otherwise, to the United States' leaving the Paris climate agreement.

  • Marginal Revolution wonders what assumptions about deep history the news of Homo sapiens' longer history overturn.

  • The Power and the Money's Noel Maurer notes that, in the area of energy costs, mid-20th century Uruguay was worse off than New Zealand.
  • The Russian Demographics Blog looks at polling on Russian opinions about the Russian Far East and its future.

  • Yorkshire Ranter Alex Harrowell is skeptical about Jeremy Paxman's claims about privacy in modern journalism.

rfmcdonald: (Default)

  • The Atlantic's Ed Yong notes the discovery of dated Homo sapiens fossils 300k years old in Morocco. (!)

  • The Atlantic reports on Twitter-driven science that has highlighted the remarkable visual acuity of the spider.

  • The Economist notes that multilingual societies can encounter more difficulties prospering than unilingual ones.

  • Torontoist notes a Thunder Bay park devoted to the idea of First Nations reconciliation.

  • The Inter Press Service reports on how gardens grown under solar tents in Bolivia can improve nutrition in poor highland villages.

  • The Toronto Star's Christopher Hume trolls Rob Ford's supporters over the new, well-designed, Etobicoke Civic Centre.Metro Toronto calculates just how many avocado toasts would go into a mortgage in the GTA.

  • MacLean's hosts a collection of twenty photos from gritty Niagara Falls, New York.

  • The National Post shows remarkable, heartbreaking photos from the flooded Toronto Islands.

  • Edward Keenan argues that the Toronto Islands' flooding should help prompt a local discussion on climate change.

rfmcdonald: (Default)

  • Anthropology.net reports on new evidence that Homo naledi may have used tools, buried their dead, and lived alongside Homo sapiens.
  • Centauri Dreams remembers an abortive solar sail mission to Halley's Comet.

  • Dangerous Minds shares photos of the "Apache" dancers of France.

  • Cody Delistraty writes about Swedish futurist Anders Sandberg and his efforts to plan for humanity's future.

  • At the Everyday Sociology Blog, Karen Sternheimer talks about her day as a sociologist.

  • Joe. My. God. notes the good news that normal young HIV patients can now expect near-normal life expectancies.

  • Language Hat looks at a recent surge of interest in Italian dialects.

  • Language Log looks at the phenomenon of East Asians taking English-language names.

  • The LRB Blog considers the dynamics of the United Kingdom's own UDI.

  • Marginal Revolution looks at the existential issues of a growing Kinshasa still disconnected from the wider world.

  • Steve Munro notes that Metrolinx will now buy vehicles from France's Alstom.

  • The New APPS Blog uses Foucault to look at the "thanatopolitics" of the Republicans.

  • The NYRB Daily looks at Trump's constitutional crisis.

  • Out There considers the issues surrounding the detection of an alien civilization less advanced than ours.

  • The Planetary Society Blog looks at the United States' planetary science exploration budget.

  • The Power and the Money's Noel Maurer looks at Argentina's underrated reputation as a destination for foreign investment.

  • Progressive Download shares some thinking about sexual orientation in the context of evolution.

  • Peter Rukavina looks at the success of wind energy generation on the Island.

  • Understanding Society takes a look at the dynamics of Rome.

  • Window on Eurasia shares a lunatic Russian scheme for a partition of eastern Europe between Russia and Germany.

rfmcdonald: (Default)

  • blogTO lists seven hidden beaches in the Toronto area.

  • The Dragon's Gaze notes the discovery of a Solar twin, Inti 1.

  • Joe. My. God. observes that this weekend was the time for Manhattanhenge in New York City.

  • Language Hat reports on the 1950s travels of Nabokov and describes the effort to preserve the languages of the Arctic.

  • The LRB Blog notes political protest in Madrid.

  • Marginal Revolution worries about the premature deindustrialization of China and its effect on Chinese workers, and notes the dominance of the New York City subway system in American transit numbers.

  • Personal Reflections' Jim Belshaw describes Homo sapiens sapiens tangled family history, Denisovans and Neanderthal and all.

  • Towleroad notes an anti-gay Vatican official charged with seducing young men.

  • Window on Eurasia notes the new Kalmyk republic mission in Moscow and describes the import of Russia's Ust-Luga port on the Baltic.

rfmcdonald: (Default)
The Australian Broadcasting Corporation reports on the confirmation of the existence of Homo floresiensis as a distinct human subspecies.

Fossils of Homo floresiensis, dubbed "the hobbits" due to their tiny stature, were discovered on the island of Flores in 2003.

Controversy has raged ever since as to whether they were an unknown branch of early humans or specimens of modern man deformed by disease.

The study, based on an analysis of the skull bones, shows once and for all that the pint-sized people were not Homo sapiens, according to the researchers.

[. . .]

One school of thought holds that so-called Flores Man descended from the larger Homo erectus and became smaller over hundreds of generations.

The proposed process for this is called "insular dwarfing".

Animals, after migrating across land bridges during periods of low sea level, wind up marooned on islands as oceans rise and their size progressively diminishes if the supply of food declines.

An adult hobbit stood one metre tall and weighed about 25 kilograms.
rfmcdonald: (Default)

  • Centauri Dreams considers gravitational waves.

  • Discover's D-Brief notes our Neanderthal genetic legacy.

  • The Dragon's Gaze looks at an inflated hot Neptune.

  • The Dragon's Tales considers how much sulfur dioxide Mars had.

  • Joe. My. God. notes Dan Savage's criticism of Log Cabin Republicans.

  • Marginal Revolution considers ways to be happy.

  • The Planetary Society Blog looks at Ok Go's new zero-gravity music video.

  • pollotenchegg notes trends in urban population growth in Ukraine, the Donbas faring particularly badly.

  • The Power and the Money's Noel Maurer wonders, after Ross Douthat, about the durability of stereotypes of American militarism and European pacifism.

  • Strange Maps notes a map of xenophobia, tracking rumours.

  • Torontoist notes that Drake got the keys to the city of Toronto.

rfmcdonald: (Default)
Drawing on recent papers simulating ancient demographics and Neanderthal cognition, Adam Benton at EvoAnth describes how easily Neanderthals could have been driven into extinction by human beings, even if they were as capable as us.

A series of computer models have shown how even if humans and Neanderthals were equally smart, we still could have beaten them.

It all boils down to our technological advantage. Humans rolled up to the Neanderthal club with some very fancy tools. We would both have hunted the same prey; so whoever had the best tools for the job would outcompete the others. Crucially, this new study shows that this would happen even if the Neanderthals outnumbered the first humans (which they likely did, given it was their home turf). And if humans only had a small technological advantage. Even a slight edge would allow us to reproduce a little bit better, soon allowing us to outnumber the Neanderthals. We could really give them a good kick whilst they were down.

Now to be fair, the Neanderthals had those fancy tools too. However, they seemed to produce them a lot less frequently. In some cases they only seem to have adopted them a few thousand years after humans arrived in the joint (which has led some to speculate they stole them from humans). Thus, even if Neanderthals were as smart as us and making the same tools as us; we brought the better tools to more parties. This would have given us the advantage in hunting resources, allowing us to outcompete the Neanderthals.

Of course, this points rest on the idea that our tools were actually better for hunting than theirs’. Sure they were fancier, but how much does that translate into better hunting ability? Can we really quantify the technological level of the two groups? We can measure a lot of variables about these tools. Some were a more efficient use of raw materials. Others could be repaired quicker. Which of these variables, if any, is the one that gave us the edge? These simulations don’t really tell the answer.

[. . .]

These simulations also identified some other ways that a small group of humans could have gained an advantage over the Neanderthal.

The most significant of these was learning ability. If it turns out we were a bit smarter than Neanderthals (or at least, a bit better at learning) then we could drive them extinct in almost any scenario. No matter how many Neanderthals were living in the region initially, or how few humans turned up, if we could learn better they would all go extinct.

This ultimately works for the same reason that having better culture works. If we can learn we can adapt, innovate, and gain that same cultural edge that would have allowed us to outcompete the Neanderthals.
rfmcdonald: (Default)
The Atlantic's Ed Yong describes how big data is being used to tease out the complicated genetic legacy of the Neanderthals in the contemporary human population.

Since 2007, Vanderbilt researchers have been coordinating an 12-institute initiative called eMERGE (short for Electronic Medical Records and Genomics), analyzing the DNA of 55,000 volunteers and comparing those sequences to the patients’ medical records. Those records are goldmines of untapped data about the participants’ phenotypes—the full collection of their traits, including things like height, weight, cholesterol levels, heart function, cancer risk, and depression symptoms. Rather than looking for genes that are related to specific traits or diseases, as many large genetics studies do, eMERGE allows researchers to look for genes related to, well, pretty much anything in those records.

“We realized that it would be relatively straightforward to identify Neanderthal DNA in all these patients and analyze their [records] for a large range of phenotypes, which could speak to all kinds of traits and effects,” says Tony Capra from Vanderbilt University, who led the new study.

And so they did. They started with 13,700 people from the eMERGE Network, and looked for associations between 135,000 Neanderthal genetic variants and 1,689 different traits. They then checked any links they found against a second group of 14,700 eMERGE volunteers. “It is an exciting study—the first systematic assessment of the phenotypic impact of Neanderthal ancestry,” says Sriram Sankararaman from Harvard Medical School, who led an earlier study on Neanderthal DNA.

Capra and his colleagues found significant associations between Neanderthal variants and a dozen phenotypes, including actinic kerastoses (patches of dry, scaly skin caused by sun exposure) and a hypercoagulable state (where blood clots form too readily in the body).

Neither of these connections were particularly surprising: “Neanderthals had been living in central Asia and Europe for several hundreds of thousands of years before modern humans, so they were better adapted to the local climate, pathogens, and diets,” Capra says. “Perhaps interbreeding gave them a heads-up on adaptations to these challenges.” For example, Neanderthal variants could have shaped the skin cells of our ancestors, allowing them to cope with varying levels of ultraviolet radiation in new parts of the world; perhaps that is why such variants affect the risk of actinic kerastoses today. Similarly, blood clots close wounds and physically trap invading microbes; by influencing clotting, Neanderthal variants could have helped early humans to cope with new diseases.
rfmcdonald: (Default)
The Dragon's Tales linked to the Cell paper "Pleistocene Mitochondrial Genomes Suggest a Single Major Dispersal of Non-Africans and a Late Glacial Population Turnover in Europe". The abstract is eye-catching.

How modern humans dispersed into Eurasia and Australasia, including the number of separate expansions and their timings, is highly debated. Two categories of models are proposed for the dispersal of non-Africans: (1) single dispersal, i.e., a single major diffusion of modern humans across Eurasia and Australasia; and (2) multiple dispersal, i.e., additional earlier population expansions that may have contributed to the genetic diversity of some present-day humans outside of Africa. Many variants of these models focus largely on Asia and Australasia, neglecting human dispersal into Europe, thus explaining only a subset of the entire colonization process outside of Africa. The genetic diversity of the first modern humans who spread into Europe during the Late Pleistocene and the impact of subsequent climatic events on their demography are largely unknown. Here we analyze 55 complete human mitochondrial genomes (mtDNAs) of hunter-gatherers spanning ∼35,000 years of European prehistory. We unexpectedly find mtDNA lineage M in individuals prior to the Last Glacial Maximum (LGM). This lineage is absent in contemporary Europeans, although it is found at high frequency in modern Asians, Australasians, and Native Americans. Dating the most recent common ancestor of each of the modern non-African mtDNA clades reveals their single, late, and rapid dispersal less than 55,000 years ago. Demographic modeling not only indicates an LGM genetic bottleneck, but also provides surprising evidence of a major population turnover in Europe around 14,500 years ago during the Late Glacial, a period of climatic instability at the end of the Pleistocene.
rfmcdonald: (Default)
I came across very recently Ann Gibbons' September 2015 Sciencemag article noting yet another remarkable turn in the history of the hominid family.

In a remarkable technical feat, researchers have sequenced DNA from fossils in Spain that are about 300,000 to 400,000 years old and have found an ancestor—or close relative—of Neandertals. The nuclear DNA, which is the oldest ever sequenced from a member of the human family, may push back the date for the origins of the distinct ancestors of Neandertals and modern humans, according to a presentation here yesterday at the fifth annual meeting of the European Society for the study of human evolution.

Ever since researchers first discovered thousands of bones and teeth from 28 individuals in the mid-1990s from Sima de los Huesos (“pit of bones”), a cave in the Atapuerca Mountains of Spain, they had noted that the fossils looked a lot like primitive Neandertals. The Sima people, who lived before Neandertals, were thought to have emerged in Europe. Yet their teeth, jaws, and large nasal cavities were among the traits that closely resembled those of Neandertals, according to a team led by paleontologist Juan-Luis Arsuaga of the Complutense University of Madrid. As a result, his team classified the fossils as members of Homo heidelbergensis, a species that lived about 600,000 to 250,000 years ago in Europe, Africa, and Asia. Many researchers have thought H. heidelbergensis gave rise to Neandertals and perhaps also to our species, H. sapiens, in the past 400,000 years or so.

But in 2013, the Sima fossils’ identity suddenly became complicated when a study of the maternally inherited mitochondrial DNA (mtDNA) from one of the bones revealed that it did not resemble that of a Neandertal. Instead, it more closely matched the mtDNA of a Denisovan, an elusive type of extinct human discovered when its DNA was sequenced from a finger bone from Denisova Cave in Siberia. That finding was puzzling, prompting researchers to speculate that perhaps the Sima fossils had interbred with very early Denisovans or that the “Denisovan” mtDNA was the signature of an even more ancient hominin lineage, such as H. erectus. At the time, researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, who had obtained the mtDNA announced that they would try to sequence the nuclear DNA of the fossils to solve the mystery.

After 2 years of intense effort, paleogeneticist Matthias Meyer of the Max Planck Institute for Evolutionary Anthropology has finally sequenced enough nuclear DNA from fossils of a tooth and a leg bone from the pit to solve the mystery. The task was especially challenging because the ancient DNA was degraded to short fragments, made up of as few as 25 to 40 single nucleotides. (Nucleotides—also known as base pairs—are the building blocks of DNA.) Although he and his colleagues did not sequence the entire genomes of the fossils, Meyer reported at the meeting that they did get 1 million to 2 million base pairs of ancient nuclear DNA.

They scanned this DNA for unique markers found only in Neandertals or Denisovans or modern humans, and found that the two Sima fossils shared far more alleles—different nucleotides at the same address in the genome—with Neandertals than Denisovans or modern humans. “Indeed, the Sima de los Huesos specimens are early Neandertals or related to early Neandertals,” suggesting that the split of Denisovans and Neandertals should be moved back in time, Meyer reported at the meeting.

Researchers at the meeting were impressed by this new breakthrough in ancient DNA research. “This has been the next frontier with ancient DNA,” says evolutionary biologist Greger Larson of the University of Oxford in the United Kingdom.
rfmcdonald: (Default)
The Dragon's Tales linked to this Nature piece by Heidi Ledford noting the imminence of human genetic engineering. The only question is where it will occur.

Concerns over the manipulation of human embryos are nothing new. Rosario Isasi, a legal scholar at McGill University in Montreal, Canada, points to two key waves of legislation over the years: one sparked by concerns about the derivation of embryonic stem cells, which was largely deemed acceptable; the other about reproductive cloning, which was largely prohibited for safety reasons.

The current regulatory mosaic is their legacy. Tetsuya Ishii, a bioethicist at Hokkaido University in Sapporo, Japan, spent nearly a year analysing relevant legislation and guidelines in 39 countries, and found that 29 have rules that could be interpreted as restricting genome editing for clinical use (M. Araki and T. Ishii Reprod. Biol. Endocrinol. 12, 108; 2014). But the 'bans' in several of these countries — including Japan, China and India — are not legally binding. “The truth is, we have guidelines but some people never follow them,” said Qi Zhou, a developmental biologist at the Chinese Academy of Sciences Institute of Zoology in Beijing, at a meeting hosted by the US National Academy of Sciences in Washington DC last week. Ishii considers the rules in nine other countries — among them Russia and Argentina — to be “ambiguous”. The United States, he notes, prohibits federal funding for research involving human embryos, and would probably require regulatory approval for human gene editing, but does not officially ban the use of the technique in the clinic. In countries where clinical use is banned, such as France and Australia, research is usually allowed as long as it meets certain restrictions and does not attempt to generate a live birth (see 'CRISPR embryos and the law').

Many researchers long for international guidelines that, even if not enforceable, could guide national lawmakers. Developing such a framework is one of the aims of ongoing discussions; the US National Academy, for example, plans to hold an international summit in December and then produce recommendations for responsible use of the technique in 2016.

But the research has already begun, and more is coming. Scientists in China announced in April that they had used CRISPR to alter the genomes of human embryos, albeit ones incapable of producing a live baby (P. Liang et al. Protein Cell 6, 363–372; 2015). Xiao-Jiang Li, a neuroscientist at Emory University in Atlanta, Georgia, who has used the technique in monkeys, says he has heard rumours that several other Chinese laboratories are already doing such experiments. And in September, developmental biologist Kathy Niakan of the Francis Crick Institute in London applied to the UK Human Fertilisation and Embryology Authority for permission to use the technique to study errors in embryo development that can contribute to infertility and miscarriage. No one so far has declared an interest in producing live babies with edited genomes, and initial experiments would suggest that it is not yet safe. But some suspect that it is only a matter of time.
rfmcdonald: (Default)
CBC carries the Thomson-Reuters article describing the discovery, in a southern Chinese cave, of evidence of an early migration by Homo sapiens into China long before the species made it to Europe.

A trove of 47 fossil human teeth from a cave in southern China is rewriting the history of the early migration of our species out of Africa, indicating Homo sapiens trekked into Asia far earlier than previously known and much earlier than into Europe.

Scientists on Wednesday announced the discovery of teeth between 80,000 and 120,000 years old that they say provide the earliest evidence of fully modern humans outside Africa.

The teeth from the Fuyan Cave site in Hunan Province's Daoxian County place our species in southern China 30,000 to 70,000 years earlier than in the eastern Mediterranean or Europe.

"Until now, the majority of the scientific community thought that Homo sapiens was not present in Asia before 50,000 years ago," said paleoanthropologist Wu Liu of the Chinese Academy of Sciences' Institute of Vertebrate Paleontology and Paleoanthropology.

Our species first appeared in East Africa about 200,000 years ago, then spread to other parts of the world, but the timing and location of these migrations has been unclear.
rfmcdonald: (Default)

  • The Dragon's Gaze links to a paper suggesting that stars commonly ingest hot Jupiters.

  • The Dragon's Tales reports on the spread of robots.

  • Far Outliers shares terms for making shoyu.

  • Joe. My. God. notes that Ashley Madison nearly bought Grindr.

  • Language Log notes the changing usage of "hemp" as a political term.

  • Lawyers, Guns and Money notes the plan to save New Orleans by abandoning the Mississippi delta.

  • The Russian Demographics blog notes the genetic distinctiveness of the Denisovans.

  • Towleroad notes the pulling-down of a Warsaw rainbow monument.

  • The Volokh Conspiracy notes the American debate over birthright citizenship.

rfmcdonald: (Default)
The Globe and Mail hosts Will Dunham's Reuters article reporting that an ancient Homo sapiens skeleton in Romania has substantial Neanderthal ancestry. That this skeleton does not belong to a population that left descendants in contemporary Europe is also noteworthy, IMHO.

You may not know it, but you probably have some Neanderthal in you. For people around the world, except sub-Saharan Africans, about 1 to 3 percent of their DNA comes from Neanderthals, our close cousins who disappeared roughly 39,000 years ago.

Scientists said on Monday a jawbone unearthed in Romania, of a man who lived about 40,000 years ago, boasts the most Neanderthal ancestry ever seen in a member of our species.

[. . .]

“We show that one of the very first modern humans that is known from Europe had a Neanderthal ancestor just four to six generations back in his family tree,” said geneticist Svante Pääbo of Germany’s Max Planck Institute for Evolutionary Anthropology.

“He carries more Neanderthal DNA than any other present-day or ancient modern human seen to date.”

Harvard Medical School geneticist David Reich said 6 to 9 percent of this individual’s genome derived from a Neanderthal ancestor.
rfmcdonald: (Default)

  • Anthropology.net notes the embarrassing discovery that one of the vertebrae believed to have been part of the skeleton of early hominid Lucy actually belonged to a baboon.

  • Antipope Charlie Stross comes up with another worrisome explanation for the Great Filter.

  • BlogTO visits the Toronto offices of photo community site 500px.

  • Centauri Dreams features a guest essay from Ashley Baldwin about near- and medium-term search strategies and technologies for exoplanets.

  • Crooked Timber examines problems with non-copyright strategies.

  • The Dragon's Gaze links to a paper noting oddities in the protoplanetary disk of AA Tauri.

  • The Dragon's Tales considers how how to make enduring software.

  • Mathew Ingram notes that Rolling Stone encountered ruin with the story of Jackie by wanting it to be true.

  • Joe. My. God. notes a New York City artist who took pictures of people in adjacent condos won the privacy suit put against him.

  • Language Hat looks at foreign influence in the French language.

  • Language Log links to a study of Ronald Reagan's speeches that finds evidence of his progression to Alzheimer's during the presidency.

  • Languages of the World considers the geopolitics of a military strike against the Iranian nuclear program.

  • Lawyers, Guns and Money argues that Jonah Lehrer was not treated unfairly.

  • Marginal Revolution approves of Larry Kramer's new GLBT-themed history of the United States.

  • Justin Petrone at North contrasts Easter as celebrated in Estonian and Russian churches.

  • Savage Minds features an essay in support of the BDS movement aimed against Israel.

  • Spacing engages David Miller on the need of urbanites to have access to nature.

  • Torontoist notes the popularity of a bill against GLBT conversion therapy at Queen's Park.

  • Towleroad observes the beginning of an opera about Grindr.

  • The Volokh Conspiracy takes issue with Gerry Trudeau's criticism of cartoons which satirize Islam.

  • Window on Eurasia looks at a Tatar woman who kept Islam alive in Soviet Moscow, argues that the sheer size of Donbas means that Russia cannot support it, looks at the centrality of the Second World War in modern Russia, and suggests the weak Ukrainian state but strong civil society is the inverse of the Russian situation.

rfmcdonald: (Default)

  • Gerry Canavan produces his own compendium of interesting links.

  • Centauri Dreams speculates about the colours indicative of extraterrestrial life, and ecologies.

  • Crooked Timber takes a look at Northern Ireland and the legacies of past violence.

  • The Dragon's Tales reports on a hominid fossil that may indicate a much greater diversity in our ancestral gene pool than we thought.

  • A Fistful of Euros' Edward Hugh wonders when the European Central Bank will start to taper interest rates.

  • The Frailest Thing warns that the promises of tech giants to free people from the shackles of the past should be seen critically.

  • On St. Patrick's Day, Joe. My. God. and Michael in Norfolk both note the extent to which attitudes towards GLBT people in Ireland have changed.

  • Lawyers, Guns and Money wonders about the good sense of going off of anti-depressants.

  • Marginal Revolution's Tyler Cowen proclaims Scarborough to be one of the world's best food cities.

  • Savage Minds makes the case for anthropologists to aid the post-cyclone people of Vanuatu.

  • Spacing interviews the NDP's Thomas Mulcair on urban issues.

  • The Volokh Conspiracy's David Bernstein is unhappy at the consequences for Israel of Netanyahu's reelection, while Lawyers, Guns and Money looks at income disparities in Israel.

  • Window on Eurasia argues that high inequality and low social mobility in Russia will doom the country, notes the potential for water-driven conflict in Central Asia, and notes Russian interest in acquiring more slots of Muslim pilgrims after Crimea's annexation.

rfmcdonald: (Default)
At IFL Science, Ken Sayers notes that, far from cleaving to the paleo diet in vogue now, early hominids have a diverse omnivorous diet.

Reconstructions of human evolution are prone to simple, overly-tidy scenarios. Our ancestors, for example, stood on two legs to look over tall grass, or began to speak because, well, they finally had something to say. Like much of our understanding of early hominid behavior, the imagined diet of our ancestors has also been over-simplified.

Take the trendy Paleo Diet which draws inspiration from how people lived during the Paleolithic or Stone Age that ran from roughly 2.6 million to 10,000 years ago. It encourages practitioners to give up the fruits of modern culinary progress – such as dairy, agricultural products and processed foods – and start living a pseudo-hunter-gatherer lifestyle, something like Lon Chaney Jr. in the film One Million BC. Adherents recommend a very specific “ancestral” menu, replete with certain percentages of energy from carbohydrates, proteins and fats, and suggested levels of physical activity. These prescriptions are drawn mainly from observations of modern humans who live at least a partial hunter-gatherer existence.

But from a scientific standpoint, these kinds of simple characterizations of our ancestors' behavior generally don’t add up. Recently, fellow anthropologist C. Owen Lovejoy and I took a close look at this crucial question in human behavioral evolution: the origins of hominid diet. We focused on the earliest phase of hominid evolution from roughly 6 to 1.6 million years ago, both before and after the first use of modified stone tools. This time frame includes, in order of appearance, the hominids Ardipithecus and Australopithecus, and the earliest members of our own genus, the comparatively brainy Homo. None of these were modern humans, which appeared much later, but rather our distant forerunners.

We examined the fossil, chemical and archaeological evidence, and also closely considered the foraging behavior of living animals. Why is this crucial? Observing animals in nature for even an hour will provide a ready answer: almost all of what an organism does on a daily basis is simply related to staying alive; that includes activities such as feeding, avoiding predators and setting itself up to reproduce. That’s the evolutionary way.

[. . .]

Researchers Tom Hatley and John Kappelman noted in 1980 that hominids have bunodont – low, with rounded cusps – back teeth that show much in common with bears and pigs. If you’ve watched these animals forage, you know they’ll eat just about anything: tubers, fruits, leafy materials and twigs, invertebrates, honey and vertebrate animals, whether scavenged or hunted. The percentage contribution of each food type to the diet will depend (you guessed it) on the energetic value of specific foods in specific habitats, at specific times of year. Evidence from the entirety of human evolution suggests that our ancestors, and even we as modern humans, are just as omnivorous.
rfmcdonald: (Default)
The Associated Press report carried by CBC is one news item among many pointed to our species' rich and diverse history.

A partial skull retrieved from a cave in northern Israel is shedding light on a pivotal juncture in early human history when our species was trekking out of Africa to populate other parts of the world and encountered our close cousins the Neanderthals.

'It is the first direct fossil evidence that modern humans and Neanderthals inhabited the same area at the same time.'- Bruce Latimer, Case Western Reserve University

Scientists said on Wednesday the upper part of the skull, the domed portion without the face or jaws, was unearthed in Manot Cave in Israel's Western Galilee. Scientific dating techniques determined the skull was about 55,000 years old.

The researchers said characteristics of the skull, dating from a time period when members of our species were thought to have been marching out of Africa, suggest the individual was closely related to the first Homo sapiens populations that later colonized Europe.

They also said the skull provides the first evidence that Homo sapiens inhabited that region at the same time as Neanderthals, our closest extinct human relative.

Tel Aviv University anthropologist Israel Hershkovitz, who led the study published in the journal Nature, called the skull "an important piece of the puzzle of the big story of human evolution."

The study in question is here.
rfmcdonald: (Default)
The Dragon's Tales linked to a EurekAlert press release relating to a new paper, "The Nasal Complex of Neanderthals: An Entry Portal to their Place in Human Ancestry". The authors argue that one element of Neanderthal morphology--their nasal passages--reveals that Neanderthals are not a mere subpopulation of Homo sapiens, but that they were a separate species.

In an extensive, multi-institution study led by SUNY Downstate Medical Center, researchers have identified new evidence supporting the growing belief that Neanderthals were a distinct species separate from modern humans (Homo sapiens), and not a subspecies of modern humans.

The study looked at the entire nasal complex of Neanderthals and involved researchers with diverse academic backgrounds. Supported by funding from the National Science Foundation and the National Institutes of Health, the research also indicates that the Neanderthal nasal complex was not adaptively inferior to that of modern humans, and that the Neanderthals' extinction was likely due to competition from modern humans and not an inability of the Neanderthal nose to process a colder and drier climate.

Samuel Márquez, PhD, associate professor and co-discipline director of gross anatomy in SUNY Downstate's Department of Cell Biology, and his team of specialists published their findings on the Neanderthal nasal complex in the November issue of The Anatomical Record, which is part of a special issue on The Vertebrate Nose: Evolution, Structure, and Function (now online).

They argue that studies of the Neanderthal nose, which have spanned over a century and a half, have been approaching this anatomical enigma from the wrong perspective. Previous work has compared Neanderthal nasal dimensions to modern human populations such as the Inuit and modern Europeans, whose nasal complexes are adapted to cold and temperate climates.

However, the current study joins a growing body of evidence that the upper respiratory tracts of this extinct group functioned via a different set of rules as a result of a separate evolutionary history and overall cranial bauplan (bodyplan), resulting in a mosaic of features not found among any population of Homo sapiens. Thus Dr. Márquez and his team of paleoanthropologists, comparative anatomists, and an otolaryngologist have contributed to the understanding of two of the most controversial topics in paleoanthropology - were Neanderthals a different species from modern humans and which aspects of their cranial morphology evolved as adaptations to cold stress.
rfmcdonald: (Default)

  • blogTO shares photos of Scarborough's motel-heavy Kingston Road.

  • Centauri Dreams features an essay by one Nick Nielsen putting forth a typology of theoretical starships.

  • The Dragon's Gaze links to one paper analyzing the albedos of hot superearths and to another paper that measured the diameter of superearth Kepler 93b to within 120 kilometers.

  • The Dragon's Tales links to one paper noting that genetic evidence seems to suggest multiple waves of migrants from Africa and another noting that the mission planners for the New Horizons Pluto probe are looking very late for a Kuiper belt object for their probe to study.

  • Eastern Approaches follows the Ukrainian elections.

  • Marginal Revolution's Tyler Cowen suggests that the BJP may have the credibility necessary to strike a deal with Pakistan.

  • Progressive Download's John Farrell notes concern for egg donors as cloning technologies which make use of human ova advance.

  • The Russian Demographics blog notes that the annexation of Crimea by Russia, combined with the secessions of Donetsk and Luhansk, would see the Ukrainian population shrink.

  • Towleroad links to an essay at Out by a man talking about his choice to make use of Truvada to prevent HIV infection.

  • The Volokh Conspiracy notes a sad legal dispute between the parents of a deceased man over the division of his ashes.

  • Window on Eurasia suggests that eastern Ukrainian separatists are trying to encourage separatism from the top down, and notes Russian tensions with the Crimean Tatar leadership.

  • Yorkshire Ranter Alex Harrowell notes the ideological and generational divides within UKIP.


rfmcdonald: (Default)rfmcdonald

September 2017

      1 2
3 4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23


RSS Atom

Style Credit

Expand Cut Tags

No cut tags
Page generated Sep. 24th, 2017 10:13 am
Powered by Dreamwidth Studios