Interesting DNA stories told by Salon IFA
SALON-IFA: from the Society of Antiquaries and the Institute of Field Archaeologists
Salon-IFA 140: 22 May 2006
SALON-IFA Editor: Christopher Catling
christopher.catling@virgin.net
Issue 141 will go out on 5 June 2006
Skulls, DNA and human hybridisation
Numerous stories have appeared in the press over the last two weeks concerning the results of bone studies and DNA analysis, so here is a quick round up of the main findings.
First, Professor Dr Robert D Martin, Provost of the Chicago Field Museum and world-renowned primatologist, has published an article in the journal Science stating that the skull found in Flors, Indonesia, is not that of a new species (Homo floriensis, aka ‘The Hobbit’) but is that of a microcephalic (congenitally small brained) individual who lived into adulthood. This is the third such study to reach that conclusion, and it results from an exhaustive comparison of the Flores skull and those of 100 human microcephalics. For the full story see the Geological Society’s website.
The first sequences of nuclear DNA to be taken from a Neanderthal have been reported at a US science meeting. Geneticist Svante Paabo and his team say they have isolated segments of genetic material from a 45,000-year-old male Neanderthal specimen found in Vindija Cave outside Zagreb. Preliminary analysis shows the bundle of DNA responsible for maleness in the Neanderthal is very different from that of modern human and chimpanzee Y chromosomes.
Anthropologist John Hawks, of the University of Wisconsin-Madison, has suggested that there is no evidence for any period of overlap between Neanderthals and modern humans in Europe. Earlier this year, new research by Paul Mellars, FSA, of Cambridge University based on improved carbon-14 dating showed that modern humans started encroaching from Israel upon Neanderthal territory in the Balkans 3,000 years sooner than previously thought. This rate suggests Neanderthals succumbed to big climate shifts or competition from modern humans for resources sooner than previously thought, so that they might have overlapped at sites in western France for only 1,000 years. Now Hawks is saying that this figure should drop to zero and William Davies, of the Centre for Human Origins at the University of Southampton, agrees, saying that ‘the dates we have relating to interaction [of Neanderthals with modern humans in Europe] will keep getting shorter’.
A survey of British skulls suggests that early Neolithic Britons had a one in twenty chance of suffering a skull fracture at the hands of someone else and a one in fifty chance of dying from their injuries. Rick Schulting of Queen's University Belfast and Michael Wysocki from the University of Central Lancashire looked at 350 skulls spanning the period from 4000 BC to 3200 BC and found that 5 per cent showed healed depressed fractures caused by a blow from a blunt instrument, such as a club, and that unhealed injuries were present in 2 per cent of the sample, suggesting these individuals died from their wounds. The actual rate of death from violence during this period could be much higher: ‘Our data shows 2 per cent lethal cranial injuries, but these are just cranial. A lot of lethal injuries will be to soft tissues and that needn't affect bone,’ Mr Wysocki said. The researchers suspect that what they are seeing is violence at the local and regional level rather than large-scale warfare. ‘We could be seeing raiding parties or cattle rustling; some of the violence may be domestic; some of it may even be ritualised’, Mr Wysocki said. The research originally appeared in the Proceedings of the Prehistoric Society journal.
Experts from Norfolk Archaeology Unit based at Norwich Castle have discovered a rare form of mitochondrial DNA identified as Romany in an eleventh-century young adult male skeleton, and are claiming this as the first recorded arrival of the Romany gene in this country. Brian Ayers, FSA, MIFA, directed the excavation in the early 1990s in the Castle mall area where the skeleton was found in a church graveyard. ‘This exciting find emphasises a more cosmopolitan Anglo-Scandinavian society’, Brian commented, adding that the find is an indication both of the mixed ethnicity of society in Norwich in the eleventh century and of the fact that humans sometimes travelled very long distances.
Modern Tuscans like to consider themselves a cut above their neighbours on the grounds that they are descended from the ancient Etruscans, who formed the first advanced civilisation in Italy, long before being conquered and subsumed by the Romans. But researcher Guido Barbujani of Ferrara University now says that a DNA comparison of Etruscan skeletons and a sample of living Tuscans shows ‘only tenuous genetic similarities’. Barbujani, the geneticist who co-ordinated the study with researchers from Stanford University in the United States, says that: ‘If the Tuscans were the direct descendants of the Etruscans the DNA should be the same’. The study, which appears in the current edition of the Proceedings of the National Academy of Sciences, concludes that most modern Tuscans are descended from non-Etruscan people.
Ian Findlay, Professor of Molecular and Forensic Diagnostics at the University of Brisbane, has concluded that Jack the Ripper, the notorious serial killer, could have been a woman. Having extracted DNA from the gum on the envelopes and postage stamps of letters sent by ‘the Ripper’ to the police, Findlay has produced results which he says ‘are inconclusive and not forensically reliable’ but that do suggest the killer was a woman. Frederick Aberline, the detective who led the investigation, also believed the killer to be female. The prime suspect is Mary Pearcey, who used a similar modus operandi to the Ripper in murdering her lover’s wife, and who was hanged for that offence in 1890.
Finally, back to the deep past. Salon’s editor has always been suspicious of any theories of human evolution that suggest a female chimp gave birth one day to a strange genetic sport and lo, the human species had arrived ─ sudden speciation simply doesn’t make sense (and in any case, who would the human sport then breed with?). Now scientists have indeed suggested that human/chimpanzee speciation was a long process, with a phase during which hybrid chimp/humans continued to breed with male chimps, perhaps resulting in further hybridisation. The conclusions come in an exhaustive analysis of the genomes of humans, chimps, gorillas and monkeys published in Nature by Dr David Reich of the Broad Institute of Harvard and the Massachusetts Institute of Technology. ‘Hybridisation between human and chimpanzee ancestors could help to explain both the wide degree of divergence seen across our genomes, as well as the relatively similar X (female) chromosomes’, Dr Reich said, adding that hybridisation is a common feature of plant speciation, and that the reason why it had not been found in animal species before ‘may simply be due to the fact that we have not been looking for it’.
Salon-IFA 140: 22 May 2006
SALON-IFA Editor: Christopher Catling
christopher.catling@virgin.net
Issue 141 will go out on 5 June 2006
Skulls, DNA and human hybridisation
Numerous stories have appeared in the press over the last two weeks concerning the results of bone studies and DNA analysis, so here is a quick round up of the main findings.
First, Professor Dr Robert D Martin, Provost of the Chicago Field Museum and world-renowned primatologist, has published an article in the journal Science stating that the skull found in Flors, Indonesia, is not that of a new species (Homo floriensis, aka ‘The Hobbit’) but is that of a microcephalic (congenitally small brained) individual who lived into adulthood. This is the third such study to reach that conclusion, and it results from an exhaustive comparison of the Flores skull and those of 100 human microcephalics. For the full story see the Geological Society’s website.
The first sequences of nuclear DNA to be taken from a Neanderthal have been reported at a US science meeting. Geneticist Svante Paabo and his team say they have isolated segments of genetic material from a 45,000-year-old male Neanderthal specimen found in Vindija Cave outside Zagreb. Preliminary analysis shows the bundle of DNA responsible for maleness in the Neanderthal is very different from that of modern human and chimpanzee Y chromosomes.
Anthropologist John Hawks, of the University of Wisconsin-Madison, has suggested that there is no evidence for any period of overlap between Neanderthals and modern humans in Europe. Earlier this year, new research by Paul Mellars, FSA, of Cambridge University based on improved carbon-14 dating showed that modern humans started encroaching from Israel upon Neanderthal territory in the Balkans 3,000 years sooner than previously thought. This rate suggests Neanderthals succumbed to big climate shifts or competition from modern humans for resources sooner than previously thought, so that they might have overlapped at sites in western France for only 1,000 years. Now Hawks is saying that this figure should drop to zero and William Davies, of the Centre for Human Origins at the University of Southampton, agrees, saying that ‘the dates we have relating to interaction [of Neanderthals with modern humans in Europe] will keep getting shorter’.
A survey of British skulls suggests that early Neolithic Britons had a one in twenty chance of suffering a skull fracture at the hands of someone else and a one in fifty chance of dying from their injuries. Rick Schulting of Queen's University Belfast and Michael Wysocki from the University of Central Lancashire looked at 350 skulls spanning the period from 4000 BC to 3200 BC and found that 5 per cent showed healed depressed fractures caused by a blow from a blunt instrument, such as a club, and that unhealed injuries were present in 2 per cent of the sample, suggesting these individuals died from their wounds. The actual rate of death from violence during this period could be much higher: ‘Our data shows 2 per cent lethal cranial injuries, but these are just cranial. A lot of lethal injuries will be to soft tissues and that needn't affect bone,’ Mr Wysocki said. The researchers suspect that what they are seeing is violence at the local and regional level rather than large-scale warfare. ‘We could be seeing raiding parties or cattle rustling; some of the violence may be domestic; some of it may even be ritualised’, Mr Wysocki said. The research originally appeared in the Proceedings of the Prehistoric Society journal.
Experts from Norfolk Archaeology Unit based at Norwich Castle have discovered a rare form of mitochondrial DNA identified as Romany in an eleventh-century young adult male skeleton, and are claiming this as the first recorded arrival of the Romany gene in this country. Brian Ayers, FSA, MIFA, directed the excavation in the early 1990s in the Castle mall area where the skeleton was found in a church graveyard. ‘This exciting find emphasises a more cosmopolitan Anglo-Scandinavian society’, Brian commented, adding that the find is an indication both of the mixed ethnicity of society in Norwich in the eleventh century and of the fact that humans sometimes travelled very long distances.
Modern Tuscans like to consider themselves a cut above their neighbours on the grounds that they are descended from the ancient Etruscans, who formed the first advanced civilisation in Italy, long before being conquered and subsumed by the Romans. But researcher Guido Barbujani of Ferrara University now says that a DNA comparison of Etruscan skeletons and a sample of living Tuscans shows ‘only tenuous genetic similarities’. Barbujani, the geneticist who co-ordinated the study with researchers from Stanford University in the United States, says that: ‘If the Tuscans were the direct descendants of the Etruscans the DNA should be the same’. The study, which appears in the current edition of the Proceedings of the National Academy of Sciences, concludes that most modern Tuscans are descended from non-Etruscan people.
Ian Findlay, Professor of Molecular and Forensic Diagnostics at the University of Brisbane, has concluded that Jack the Ripper, the notorious serial killer, could have been a woman. Having extracted DNA from the gum on the envelopes and postage stamps of letters sent by ‘the Ripper’ to the police, Findlay has produced results which he says ‘are inconclusive and not forensically reliable’ but that do suggest the killer was a woman. Frederick Aberline, the detective who led the investigation, also believed the killer to be female. The prime suspect is Mary Pearcey, who used a similar modus operandi to the Ripper in murdering her lover’s wife, and who was hanged for that offence in 1890.
Finally, back to the deep past. Salon’s editor has always been suspicious of any theories of human evolution that suggest a female chimp gave birth one day to a strange genetic sport and lo, the human species had arrived ─ sudden speciation simply doesn’t make sense (and in any case, who would the human sport then breed with?). Now scientists have indeed suggested that human/chimpanzee speciation was a long process, with a phase during which hybrid chimp/humans continued to breed with male chimps, perhaps resulting in further hybridisation. The conclusions come in an exhaustive analysis of the genomes of humans, chimps, gorillas and monkeys published in Nature by Dr David Reich of the Broad Institute of Harvard and the Massachusetts Institute of Technology. ‘Hybridisation between human and chimpanzee ancestors could help to explain both the wide degree of divergence seen across our genomes, as well as the relatively similar X (female) chromosomes’, Dr Reich said, adding that hybridisation is a common feature of plant speciation, and that the reason why it had not been found in animal species before ‘may simply be due to the fact that we have not been looking for it’.
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