HENRY

Scientific American covers the human diaspora in a nice broad-brush overview:

Fifty or sixty thousand years ago a small band of Africans—a few hundred or even several thousand—crossed the strait in tiny boats, never to return.

The reason they left their homeland in eastern Africa is not completely understood. Perhaps the climate changed, or once abundant shellfish stocks vanished. But some things are fairly certain. Those first trekkers out of Africa brought with them the physical and behavioral traits—the large brains and the capacity for language—that characterize fully modern humans. From their bivouac on the Asian continent in what is now Yemen, they set out on a decamillennial journey that spanned continents and land bridges and reached all the way to Tierra del Fuego, at the bottom of South America.

Posted on July 9th, 2008 by Simon Greenhill in africa, americas, anthropology, europe, genetics, human prehistory, mtDNA    No Comments

….and the award for the stupidest science story I’ve seen in months goes to LiveScience.com for “Cave Men Loved to Sing“, in which we’re told that our cave-dwelling ancestors used echo-location:

With only dull light available from a torch, which couldn’t be carried into very narrow passages, the ancient hunters had to use their voices like sonar to explore the crooks and crannies of a newfound cave, Reznikoff explained.

“When acting in a cave in conditions similar to prehistoric ones … the surroundings a few meters ahead are almost completely dark,” he said, adding that “since sound reaches much farther than reduced light, especially in irregular surroundings, the only possibility and security is to explore the cave with the voice and its echoing effects.”

This work is good, because…  “(some work was done in past years and combined with the latest findings)”.  A scientific paper being based off previous findings… Fancy that.

The conclusions? -

Because Paleolithic humans had a deep connection with the melodic properties that helped them navigate in a cave, they likely celebrated the unique acoustics by singing in conjunction with their painting sessions.

Posted on July 4th, 2008 by Simon Greenhill in anthropology, cultural evolution, europe, evolution, genetics, human prehistory, it-was-better-in-my-day, language, music, stupidity    (3) Comments

Today’s Science sees the publication of a phylogenomic study of 196 bird species, which has some rather marked differences to the traditional phylogenies of bird species. Abstract says -

Deep avian evolutionary relationships have been difficult to resolve as a result of a putative explosive radiation. Our study examined ~32 kilobases of aligned nuclear DNA sequences from 19 independent loci for 169 species, representing all major extant groups, and recovered a robust phylogeny from a genome-wide signal supported by multiple analytical methods. We documented well-supported, previously unrecognized interordinal relationships (such as a sister relationship between passerines and parrots) and corroborated previously contentious groupings (such as flamingos and grebes). Our conclusions challenge current classifications and alter our understanding of trait evolution; for example, some diurnal birds evolved from nocturnal ancestors.

Abstract is here. Much news coverage will be forthcoming, I suspect, and I’ll link to some of these as they come through.

Update: GrrlScientist has covers the paper excellently (although, not enough phylogenetic details for my liking :)

Posted on June 27th, 2008 by Simon Greenhill in birds, evolution, genetics, phylogenetics    No Comments

& in P.N.A.S. - Is an eclipse described in the Odyssey?

Plutarch and Heraclitus believed a certain passage in the 20th book of the Odyssey (”Theoclymenus’s prophecy”) to be a poetic description of a total solar eclipse. In the late 1920s, Schoch and Neugebauer computed that the solar eclipse of 16 April 1178 B.C.E. was total over the Ionian Islands and was the only suitable eclipse in more than a century to agree with classical estimates of the decade-earlier sack of Troy around 1192–1184 B.C.E.

However, much skepticism remains about whether the verses refer to this, or any, eclipse. To contribute to the issue independently of the disputed eclipse reference, we analyze other astronomical references in the Epic, without assuming the existence of an eclipse, and search for dates matching the astronomical phenomena we believe they describe.

We use three overt astronomical references in the epic: to Boötes and the Pleiades, Venus, and the New Moon; we supplement them with a conjectural identification of Hermes’s trip to Ogygia as relating to the motion of planet Mercury. Performing an exhaustive search of all possible dates in the span 1250–1115 B.C., we looked to match these phenomena in the order and manner that the text describes. In that period, a single date closely matches our references: 16 April 1178 B.C.E. We speculate that these references, plus the disputed eclipse reference, may refer to that specific eclipse.

Posted on June 25th, 2008 by Simon Greenhill in anthropology, art, books    No Comments

Paul Ehrlich talks about his recent study of Polynesian canoes, and whether human culture evolves via natural selection:

Biologists have a pretty good idea of both how flies become resistant to DDT and how humans and primates have diverged over time. That’s because the mechanism underlying these processes is the same. Using evolution we can understand how organisms generally change their stores of genetic information (DNA and RNA), alter their observable characteristics, and diversify.

We do not understand how cultures evolve nearly so well.

Posted on June 24th, 2008 by Simon Greenhill in anthropology, cultural evolution, evolution, genetics, human prehistory, people    (3) Comments

Stephen Shennan in the 2008 Annual Review of Anthropology (doi):

The term evolution in archaeology has accumulated an enormous range of meanings, with different implications, over many years. Traditionally, however, when not referring to the biological evolution of putatively ancestral species, it has occurred most commonly in the phrase cultural evolution (sometimes used interchangeably with social or sociocultural evo- lution), referring to the history of what are conceived as the key long-term trends in human history: from foraging to farming, or from farming to the origins of civilization and the state, accompanied by such developments as increased population, greater social complexity and inequality, and more complex technologies.

More recently, the term has increasingly come to refer to the idea that the processes producing cultural stability and change are analogous in important respects to those of biological evolution: On this view, just as biological evolution is characterized by changing frequencies of genes in populations through time as a result of such processes as natural selection, so cultural evolution refers to the changing distributions of cultural attributes in populations, likewise affected by processes such as natural selection but also by others that have no analog in genetic evolution. In fact, to understand changing patterns of human behavior and organization we need to take account of both the biological and the cultural dimensions.

Posted on June 24th, 2008 by Simon Greenhill in cultural evolution, evolution, people, phylogenetics    (1) Comment

Remember the amazing lost tribe that was being hawked all over the news a few weeks ago? Ahh, not so lost after all. The real story is actually a whole lot more interesting:

…far from being unknown, the tribe’s existence has been noted since 1910 and the mission to photograph them was undertaken in order to prove that ‘uncontacted’ tribes still existed in an area endangered by the menace of the logging industry….

According to his account, the Brazilian state of Acre offered him the use of an aircraft for three days. ‘I had years of GPS co-ordinates,’ he said. Meirelles had another clue to the tribe’s precise location. ‘A friend of mine sent me some Google Earth co-ordinates and maps that showed a strange clearing in the middle of the forest and asked me what that was,’ he said. ‘I saw the co-ordinates and realised that it was close to the area I had been exploring with my son – so I needed to fly over it.’…

…’When I saw them painted red, I was satisfied, I was happy,’ he said. ‘Because painted red means they are ready for war, which to me says they are happy and healthy defending their territory.‘

Posted on June 23rd, 2008 by Simon Greenhill in americas, anthropology, bongo-bongoism, culture, language preservation    (3) Comments