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Assorted Personal Notations, Essays, and Other Jottings

Posts Tagged ‘human beings

[BLOG] Some Thursday links

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  • blogTO notes the opening of a new Taiwanese fried chicken restaurant location in Toronto.
  • Centauri Dreams notes an odd crater on Charon.
  • D-Brief reports on a study suggesting that geography–specifically, topography–can influence the number of consonants in a language.
  • The Dragon’s Gaze reports on the craziness of the KOI-89 planetary system and suggests Kepler-91b might have a Trojan companion.
  • The Dragon’s Tales reports on American fears of a shortage of aircraft carriers.
  • The New APPS Blog considers if neurons have preferences.
  • Personal Reflections’ Jim Belshaw talks of the British Museum.
  • The Planetary Society Blog reports on new rover science on Mars.
  • Peter Rukavina celebrates the 20th anniversary of the Prince Edward Island government website, among other things.
  • Savage Minds notes that these days, we don’t have much time for slowness.
  • Window on Eurasia suggests student surveys in Moscow and St. Petersburg indicate high levels of ethnic and religious tension.

[BLOG] Some Monday links

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  • At Alpha Sources, although Claus Vistesen is rightly gloomy about the prospects for the Italian economy, he thinks there may be a cyclical upturn coming.
  • The Dragon’s Gaze notes the warping of the protoplanetary disk of AA Tauri.
  • The Dragon’s Tales notes exciting ancient archeological finds in Indonesia possibly belonging to Homo floresiensis.
  • Geocurrents notes the controversy over an India-Africa summit.
  • Language Log notes an instance of tardy students being forced to draw a Chinese character.
  • Languages of the World examines the genetics of Napoleon Bonaparte.
  • Lawyers, Guns and Money notes the history wars of South Korea.
  • Marginal Revolution notes an East German village whose inhabitants will soon be far outnumbered by Syrian refugees.
  • Personal Reflections reacts to the Turkish election and Chinese demographics.
  • The Planetary Society Blog notes the vast data gathered from Ceres.
  • Registan suggests Russia’s elites are operating according to frightening theories of geopolitics.
  • Cheri Lucas Rowlands shares photos of a trip to the Southwest.
  • The Russian Demographics Blog looks at the demographics of the Donbas in 1926.
  • Whatever’s John Scalzi thinks the 50 dollar Amazon Fire tablet is worth it.
  • Window on Eurasia suggests Russian nationalists will be a lasting threat to Ukraine and suggests non-Donbas Ukrainians will soon be deported from Russia.
  • Yorkshire Ranter Alex Harrowell notes a remarkable sort of organizational artifact.

[LINK] “Where in the world could the first CRISPR baby be born?”

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.

Written by Randy McDonald

October 16, 2015 at 10:29 pm

[LINK] “Evidence of earliest modern humans outside Africa found in China”

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.

Written by Randy McDonald

October 14, 2015 at 9:41 pm

[LINK] “New Human Ancestor Walked Like Us, Climbed Like an Ape”

National Geographic‘s Nadia Drake reports about the latest analyses of Homo naledi.

The mysterious human ancestor called Homo naledi was primed for success in a prehistoric triathlon, new research shows—if the challenges were walking upright, climbing trees, and handily wielding tools.

Based on fossils retrieved from South Africa’s Rising Star cave, two teams reconstructed the locomotor habits of Homo naledi, reported Tuesday in Nature Communications. With funding from National Geographic, one took a close look at 107 foot bones, the other at 26 bones from a nearly complete right hand.

In most respects, the H. naledi foot looks surprisingly like a modern human’s. Its ankle joint, parallel big toe and wide heel bone belong to a striding biped, a creature fully adapted to efficiently walking upright on two legs. But its lower arch and curved toe bones are more ape-like.

The hand, with its curved fingers, indicates that H. naledi were strong climbers—and yet the long, strong thumb and shock-absorbing wrist could also have been capable of manipulating tools (though no tools have been found yet).

Written by Randy McDonald

October 7, 2015 at 9:11 pm

Posted in Science

Tagged with , , ,

[BLOG] Some Wednesday links

  • James Bow links to some things he wrote over the past summer.
  • The Broadside Blog’s Caitlin Kelly argues journalists are just trying to do their jobs.
  • Centauri Dreams looks at some unusual orbits suited for space missions.
  • Crooked Timber suggests Bitcoin is literally a waste of energy.
  • The Dragon’s Gaze talks about using machine learning to discover exoplanets.
  • The Dragon’s Tales shares pictures of Neanderthal art, talks about Elon Musk’s plan for terraforming Mars, notes Lukashenko does not want a Russian base in Belarus, and reports on the stabilization of the front line in Donbas.
  • Language Hat notes false etymologies of some Russian words as indigenous.
  • Languages of the World suggests there is a close link between genetics and language.
  • Lawyers, Guns and Money notes the extent to which Jamaica has suffered because of colonialism, and examines the relationship of domestic work with slavery.
  • Marginal Revolution notes that women in Japan have surpassed women in the United States re: workforce participation.
  • Otto Pohl links to online publications on Russian Germans, and on Crimean Tatars.
  • The Russian Demographics Blog looks at nostalgia in Belarus for the Grand Duchy of Lithuania.
  • Transit Toronto notes that the TTC is installing bike repair stations at some of its stations.
  • Savage Minds considers reasons anthropologists should be concerned with the security of their fieldwork and other data.
  • Window on Eurasia suggests Ukraine could split back into Russia’s sphere of influence if it is not careful, notes the possible strength of autonomist sentiment in Tatarstan, looks at opposition in Belarus to a new Russian base while suggesting Putin is building Belarusian nationalism.

[LINK] “Humans have more primitive hands than chimpanzees”

Science does its readers a service in reporting new findings suggesting that chimpanzees cannot be taken to represent the original state of proto-humans, that this species also evolved over time. Michael Balter writes.

Humans and chimps diverged from a common ancestor perhaps about 7 million years ago, and their hands now look very different. We have a relatively long thumb and shorter fingers, which allows us to touch our thumbs to any point along our fingers and thus easily grasp objects. Chimps, on the other hand, have much longer fingers and shorter thumbs, perfect for swinging in trees but much less handy for precision grasping. For decades the dominant view among researchers was that the common ancestor of chimps and humans had chimplike hands, and that the human hand changed in response to the pressures of natural selection to make us better toolmakers.

But recently some researchers have begun to challenge the idea that the human hand fundamentally changed its proportions after the evolutionary split with chimps. The earliest humanmade stone tools are thought to date back 3.3 million years, but new evidence has emerged that some of the earliest members of the human line—such as the 4.4-million-year-old Ardipithecus ramidus (“Ardi”)—had hands that resembled those of modern humans rather than chimps, even though it did not make tools. And back in 2010, a team led by paleoanthropologist Sergio Almécija, now at George Washington University in Washington, D.C., began arguing that even earlier human relatives, dating to 6 million years ago—very soon after the human-chimp evolutionary split—already had humanlike hands as well. This even included the ability to press the thumb against the fingers with considerable force, a key aspect of precision gripping.

To get a grasp on what early hands really looked like, Almécija and his colleagues analyzed the thumb and finger proportions of a large number of living apes and monkeys, including modern humans. They then compared these to the hands of several extinct species of apes and early humans, including Ardi, the Neandertals, and the 2-million-year-old Australopithecus sediba from South Africa, which its discoverers controversially think might be a direct ancestor of humans. The sample also included the 25-million-year-old fossil ape known as Proconsul.

The team crunched the measurements from all these samples using sophisticated statistical methods designed to determine the course of hand evolution over time. The researchers found that the hand of the common ancestor of chimps and humans, and perhaps also earlier ape ancestors, had a relatively long thumb and shorter fingers, similar to that of humans today. (Gorillas, which spend most of their time on the ground and not in trees, have similarly shaped hands.) Thus, the human hand retains these more “primitive” proportions, whereas the elongated fingers and shorter thumbs of chimps, as well as orangutans, represent a more specialized and “derived” form ideal for life in the trees, the team reports today in Nature Communications.

Written by Randy McDonald

October 3, 2015 at 3:57 am

Posted in Science

Tagged with , , , ,


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