MetaFilter posts tagged with human and science

Neanderthal-Human Babies

wantwit — Thu, 20 Mar 2008 16:24:42 -0800

Any admixture would have to be driven by male Neanderthals. Two years ago we discussed morphological evidence of nontrivial interbreeding. Since then Neanderthal DNA has been examined for genetic support for this model of human evolution, largely contradicting the belief in Neanderthal contribution to modern humanity. Indeed any contribution from the Neanderthal gene pool to the evolution of modern humans might be very rare and indeed it appears that the best candidate gene thus (MC1R) far likely was a result of convergent evolution. EXCERPT: It is now clear that the level of interbreeding between the two populations, if any, was so low that we are unlikely to find any neutrally evolving Neanderthal alleles in modern populations. However, it is possible that low levels of interbreeding could have led to the adaptive transfer of some alleles between species (introgression). Beneficial alleles can persist in interspecific hybrids even when the hybrids are less fit than either parent population as long as the hybrids are fertile [37]. As hybrids back-cross to a parent population, most introduced alleles will be lost to drift or to negative selection; some beneficial alleles, however, may be maintained in subsequent generations. Claims have been made for adaptive introgression from Neanderthals into populations of modern humans at the microcephalin [38] and the tau [39] loci. Some proponents of the multiregional model have gone so far as to suggest that adaptive introgression was a primary source of beneficial alleles during the evolution of modern humans [40]. While we regard this latter idea as unsupported by the available Neanderthal and human genome sequences, it is worth considering the possibility that a very limited amount of adaptive introgression has occurred. MC1R is a good a priori candidate for adaptive introgression. It is thought that light skin is favored in Europe as a compromise between the need for vitamin D synthesis and the need to prevent folate photolysis, both caused by UV radiation [41]. Several genes affecting skin color are known to have been positively selected in European populations [21,22], though studies of MC1R evolution have come to different conclusions [22,42,43]. Jolly has pointed out that the easiest way for early modern humans entering Europe to evolve light skin would be to acquire the necessary genes from Neanderthals rather than to evolve them de novo [44]. If the low-activity MC1R variant is positively selected in Europe, then MC1R presents a good opportunity to test for evidence of adaptive introgression from Neanderthals to modern humans. However, although Neanderthals and modern Europeans share a low-activity MC1R phenotype, the genotype is different (see above), which argues against significant adaptive introgression. The hypothesis could be tested more rigorously using Neanderthal sequence from other loci affecting skin color with a clearer signal of positive selection in Europeans.

Human Rights Watch, Watched

Postroad — Mon, 21 Aug 2006 12:00:04 -0800

Human Rights Watch, Watched "Who will guard the guardians?" asked Roman satirist Juvenal. Now we must ask, who is watching Human Rights Watch, one of the world's best-financed and most influential human rights organizations? It turns out that they cook the books about facts, cheat on interviews, and put out pre-determined conclusions that are driven more by their ideology than by evidence. These are serious accusations, and they are demonstrably true.

Switching off self-awareness

0bvious — Thu, 20 Apr 2006 19:16:23 -0800

Researchers have found that prolonged concentration on a difficult task actually switches off a person's self awareness. Fancy experiencing this sensation for yourself? That would be an oxymoron in existence. Just lay back and let the orgasm take hold.

The Simulacrisation of Technology into Life

0bvious — Wed, 15 Mar 2006 20:09:26 -0800

As the Pentagon ousts plans to turn insects into cyber war machines you'd be forgiven for asking the question: Where does the real digital end and the faked life begin? Are we simulating life synthetically? or just speeding up an entirely natural process? Technologically engineered life is here to stay. Its not far fetched to speculate that simulacra may become all there is.

Clonycavan Styling Gel - 2000 years of cool or your money back!

0bvious — Tue, 17 Jan 2006 21:06:41 -0800

Body, volume, style and shine with long-lasting power. Clonycavan Styling Gel, along with mummification in Irish peat, works together with your freshly disemboweled corpse to protect hair from the disruptive power of 2000 years of rigor-mortis.

The concept of the Transhuman: human, the self, consciousness and their effects on the law

0bvious — Tue, 13 Dec 2005 17:43:01 -0800

The first Transhuman Conference On the Law of Transhuman Persons: Whether or not you believe humans are set to evolve into gods, or AI is destined to achieve self-awareness the idea of the Transhuman is a thought provoking concept. Philosophers have debated the nature of the self, of the human for millennia. Is it time to start drafting new laws to govern all possible sentient beings on this planet? or is it all just a science of fiction? a comfortable humanist illusion?

This so called reality

0bvious — Tue, 22 Nov 2005 01:38:08 -0800

If the universe is a hologram and the healthy human brain a valve of consciousness then where'd this mental infinity come from? Are we simply living the simulacrum? Or does Pi protect us all, forever, infinitely?

Check out the big brains on these guys!

taz — Thu, 23 Sep 2004 02:33:11 -0800

Human Intelligence is a good site from Indiana University that looks at historical influences and current controversies surrounding the study of intelligence. Find out more about topics such as "the Mozart Effect", the theory of multiple intelligences, and the influence of birth order on intelligence, and then browse the brains behind the history of inquiry into human intellect.

Morphic — Wed, 23 Oct 2002 15:43:38 -0800

The strange range of human behavior continues to draw us like moths to a flame. Consider Amanda Fielding who continually performed self-surgery on her braincase, Catharina Geisslerin, the woman who vomited frogs, and the Collyer brothers, who collected so much junk that it crushed them in their own home. Samuel Johnson, compiler of the first dictionary of the English language, was compelled to whirl, twist, and make highly ritualized hand motions when going through doors. When he went for a walk, he touched every post he passed. If he missed one, he went back to touch it. Recent research suggests that obsessive-compulsive child behaviors can be caused by strep infection. Who do you think are the most interesting, eccentric, and compulsive personalities?

mkultra — Fri, 12 Jul 2002 06:50:09 -0800

What the law show say about cloning. Francis Fukuyama and Robert Wright, who have written about technology and "societal evolution", discuss the pros and cons of genetic engineering. This is not a discussion about the finer points of technology, but rather the philosophical implications of moving forward.

briank — Tue, 10 Jul 2001 06:46:32 -0800

It's all over, boys, we're obsolete A team of Australian scientists has announced that they've found a way to fertilize human ova with somatic cells instead of sperm. No actual living babies have been produced yet, but they expect results within the year.