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Native Africans ‘interbred with another species 35 000 years ago’: scientists

Pigmy villagers in Uganda near Lake Bunyonyi

According to a news report of the scientific journal Nature, “our ancestors bred with other species in the Homo genus, according to a study published… in the Proceedings of the National Academy of Sciences¹. The authors say that up to 2% of the genomes of some modern African populations may originally come from a closely related species.”

Palaeontologists have long wondered whether modern humans came from a single, genetically isolated population of hominids or whether we are a genetic mix of various hominid species.

Last year, an analysis comparing the Neanderthal genome sequence to that of modern H. sapiens showed that some interbreeding did take place between the two species in Europe some time between 80 and 30,000 years ago and that, to a certain extent, Neanderthals ‘live on’ in the genes of modern humans².

It has been a mystery whether similar genetic mixing took place among Homo species even earlier, before the populations that became modern humans left Africa.

To find out, evolutionary biologist Michael Hammer at the University of Arizona in Tucson and his colleagues studied DNA from two African hunter-gatherer groups, the Biaka Pygmies and the San, as well as from a West African agricultural population known as the Mandenka.

Each of these groups is descended from populations that are thought to have remained in Africa, meaning they would have avoided the genetic bottleneck effect that usually occurs with migration. This means the groups show particularly high genetic diversity, which makes their genomes more likely to have retained evidence of ancient genetic mixing.

“We need to modify the standard model

of human origins.”

To find signs of infiltration from other Homospecies, the researchers looked at 61 non-coding DNA regions in all three groups. Because direct comparison to archaic specimens wasn’t possible, the authors used computer models to simulate how infiltration from different populations might have affected patterns of variation within modern genomes.

Then they looked for such patterns of variation in the DNA of the three African populations. On chromosomes 4, 13 and 18, the researchers found genetic regions that were more divergent on average than known modern sequences at the same locations, hinting at a different origin.

Mixing things up

Hammer and his colleagues argue that roughly 2% of the genetic material found in these modern African populations was inserted into the human genome some 35,000 years ago. They say these sequences must have come from a now-extinct member of the Homogenus that broke away from the modern human lineage around 700,000 years ago.

Hammer says this disproves the conventional view that we are descended from a single population that arose in Africa and replaced all other Homo species without interbreeding. “We need to modify the standard model of human origins,” he says.

Geneticist Sarah Tishkoff, who studies population genetics and human evolution at the University of Pennsylvania in Philadelphia, is more cautious. “This raises the possibility that there may have been ancient admixture with archaic populations,” she says.

But some researchers will require yet more convincing. “The authors model differences in very small parameters, such as the difference between no admixture and 1-2% admixture with an archaic population,” says anthropologist Brenna Henn, a graduate student at Stanford University in Palo Alto, California. “The ability to discern complex models of demographic history with such a small data set, when many of the basic features of African genomes and history remain unknown, concerns me.”

Tishkoff would also like to see further work. “Analyses of whole genome sequences of these populations will be necessary to more definitively test this hypothesis,” she says.

References

Hammer, M. F. et al. Proc. Natl Acad. Sci. USAhttp://dx.doi.org/10.1073/pnas.1109300108 (2011).
Green, R. E. et al. Science 328, 710-722 (2010). | Article | PubMed | ISI | ChemPort |

Digital dementia

Doctors in South Korea are reporting a surge in “digital dementia” among young people who have become so reliant on electronic devices that they can no longer remember everyday details like their phone numbers.

South Korea is one of the most digitally connected nations in the world and the problem of internet addiction among both adults and children was recognised as far back as the late 1990s.

That is now developing into the early onset of digital dementia – a term coined in South Korea – meaning a deterioration in cognitive abilities that is more commonly seen in people who have suffered a head injury or psychiatric illness.

“Over-use of smartphones and game devices hampers the balanced development of the brain,” Byun Gi-won, a doctor at the Balance Brain Centre in Seoul, told the JoongAng Daily newspaper.

“Heavy users are likely to develop the left side of their brains, leaving the right side untapped or underdeveloped,” he said.

The right side of the brain is linked with concentration and its failure to develop will affect attention and memory span, which could in as many as 15 per cent of cases lead to the early onset of dementia.

Sufferers are also reported to suffer emotional underdevelopment, with children more at risk than adults because their brains are still growing.

The situation appears to be worsening, doctors report, with the percentage of people aged between 10 and 19 who use their smartphones for more than seven hours every day leaping to 18.4 per cent, an increase of seven per cent from last year.

More than 67 per cent of South Koreans have a smartphone, the highest in the world, with that figure standing at more than 64 per cent in teenagers, up from 21.4 per cent in 2011, according to the Ministry of Science, ICT and Future Planning.

Dr Manfred Spitzer, a German neuroscientist, published a book titled “Digital Dementia” in 2012 that warned parents and teachers of the dangers of allowing children to spend too much time on a laptop, mobile phone or other electronic devices.

Dr Spitzer warned that the deficits in brain development are irreversible and called for digital media to be banned from German classrooms before children become “addicted.” – The Telegraph

Cell phones lead to higher levels of violence throughout Africa

Much research and media attention has been devoted to exploring rapidly emerging African countries in recent years. In addition to extraordinarily high GDP growth rates, many African countries have seen their middle classes grow substantially and demand goods and services that were formerly available only to individuals in more developed countries. Cell phone use in Africa has increased substantially in recent years; its nearly 649 million mobile users in 2011 made it the second-largest market for mobile phones in the world after Asia.

Furthermore, the continent has the fastest-growing cell phone market in the world, maintaining an annual growth rate of almost 20% since 2007. This has substantially contributed to economic development within the continent as a result of various innovations and improvements, from mobile banking to faster communications between merchants and customers, as the World Bank notes. In Kenya, the success of the mobile banking system M-pesa has opened the door for a multitude of mobile phone tech startups, prompting some to refer to the country as the “Silicon Savannah.” (It should be noted, however, that mobile phone technology in Africa frequently does not afford robust Internet access, with all its innovation potential.)

The benefits of mobile technology in other regions are widely hailed. The availability of cell phones and use of social media is often credited with playing a key role in the Arab Spring, which toppled dictatorships in Egypt and Tunisia, and sparked protest movements throughout the Middle East and North Africa. In Mozambique, cell phones have been shown to improve voter education and political participation, while in Namibia cell phone usage has allowed citizens to hold their government officials more accountable and reduce corruption. Although much research has been done on the rise of technology in the developing world and its positive dimensions for politics, very little research has been done regarding possible negative externalities of increased communications capacity, such as improving the organizational abilities of violent groups to incite more conflict.

A 2013 paper from Duke University and the German Institute of Global and Area Studies published in the American Political Science Review, “Technology and Collective Action: The Effect of Cell Phone Coverage and Political Violence in Africa,” examines the impact that cell phones have had on violent conflict on the continent. The authors, Jan H. Pierskalla and Florian M. Hollenbach, utilize conflict data from the UCDP Georeferenced Event Data Set, which includes data on organized violence from 1989 to 2010, and data on cell phone coverage from the GSM Association, a global association of mobile phone service providers. The authors use various statistical techniques to account for economic, social and geographical factors related to conflict and to determine whether there is indeed an association between cell phone coverage and violent conflict in the context of Africa.

Key findings include:

– Even when confounding variables such as income, inequality, ethnic fractionalization, geography are accounted for, increases in cell phone coverage are associated with higher levels of violence throughout Africa.
– When evaluated on an individual country level, the impact of cell phone coverage on conflict is also significant within each country.
– Greater cell phone coverage leads to more conflict in “areas with structural conditions that favor violence” than those where the conditions do not favor violence; it “enables groups to overcome their collective action and coordination problems more easily, which translates to more organized conflict events.”
– The authors conclude that “cell phones lead to a boost in the capacity of rebels to communicate and monitor in-group behavior, thus increasing in-group cooperation. Furthermore, cell phones allow for coordination of insurgent activity across geographically distant locations.”

“We do not believe,” the researchers caution, “that the spread of cell phone technology has an overall negative effect on the African continent. The increase in violence induced by better communication might represent a short-term technological shock, while the positive effects of better communication networks on growth and political behavior may mitigate root causes of conflict in the long run.” The authors suggest that more research must be done to determine how communication technology, such as cell phones, impacts various forms of collective action, whether violent or non-violent, in Africa. They also note that prior research on the connection between cell phone capacity and violence — namely, the 2012 working paper “Is the Phone Mightier than the Sword? Cell Phones and Insurgent Violence in Iraq” — observed the opposite effect: Mobile technology was associated with decreased insurgent violence in Iraq.

Related research: The World Bank’s 2012 report “eTransform Africa: The Transformational Use of Information and Communication Technologies in Africa” examines a wide variety of areas, including agriculture, health, education and governance. The report discusses the implications of Africa’s so-called “mobile decade.” – journalistresource.org

Struggling to fight ‘totally drug-resistant’ Tuberculosis in South Africa

Patients of the TB center in Khayelitsha, South Africa, wait to see doctors, March 23, 2009. Tuberculosis is a contagious lung disease that spreads through the air, including through coughing and sneezing.

In a patient’s fight against tuberculosis—the bacterial lung disease that kills more people annually than any infectious disease besides HIV— doctors have more than 10 drugs from which to choose. Most of those didn’t work for Uvistra Naidoo, a South African doctor who contracted the disease in his clinic. For those who contract the disease now, maybe none of them will.

A new paper published earlier this week in the Centers for Disease Control and Prevention’s Emerging Infectious Diseases journal warns that the first cases of “totally drug-resistant” tuberculosis have been found in South Africa and that the disease is “virtually untreatable.”

Like many bacterial diseases, tuberculosis has been evolving to fend off many effective antibiotics, making it more difficult to treat. But even treatable forms of the disease are particularly tricky to cure; drug sensitive strains must be treated with a six-month course of antibiotics. Tougher cases require long-term hospitalization and a regimen of harsh drugs that can last years.

Naidoo, then an avid runner, says he continued training for months with the disease, which affects more than 389,000 South Africans annually (about one fourth of Africa’s cases), according to the World Health Organization. It wasn’t until he went to visit his family in Durban (he had been working with TB patients in a pediatric clinic in Cape Town) that his family noticed he had lost more than 30 pounds.

“I had flu symptoms and chest pains, but I was still running so I didn’t think anything was wrong,” he says. But when he went in for an X-ray, doctors found that his entire right lung had filled with fluid. Within weeks, he was on his deathbed as his body wasn’t responding to the most commonly prescribed antibiotics.

“One night I nearly passed away—it didn’t look good,” he says.

His father, also a physician, suggested that he may have had an emerging MDR, or a multi drug-resistant strain of TB. The emergence of MDR and its even more dangerous cousin, XDR (extremely drug-resistant TB), have pushed tuberculosis cure rates in the country from a high of 73 percent in 2008 down to 53 percent in 2010.

Naidoo survived the night and doctors eventually found a treatment regimen that worked, but he was in and out of the hospital for three years, and the drugs’ side effects were almost unbearable, he says. He developed Stevens-Johnson Syndrome, a complication that causes layers of skin to separate from each other and can be deadly. He regularly bled from his eyes. He fell into a deep depression.

“The TB doesn’t feel like it’s killing you, but the drugs do. I am a doctor and was informed that the drugs you take make you feel worse,” he says. “My case was three years long. I don’t think the average patient has that kind of patience.”

At King George V hospital in Durban—one of South Africa’s most popular TB clinics, which specifically treats XDR patients—the 200 beds are always full, and there’s a four- to six-week waitlist for new patients.

William Bishai, of the Johns Hopkins Center for TB Research Laboratory and head of the KwaZulu-Natal Research Institute for Tuberculosis and HIV in South Africa, works with Naidoo and says his commitment to getting better is uncharacteristic in South Africa. TB is particularly easy to contract among people who have compromised immune systems due to HIV infection—a group that makes up about 12 percent of the country’s population.

“There’s a co-infection problem with HIV—a lot of XDR patients also have HIV and have to take eight TB drugs in addition to their HIV retrovirals,” he says. “The average uneducated person would be prone to giving up. There have been a number of suicides at King George V.” – usnews.com

The rise of the machine

Early in his first term Barack Obama joked that he would “keep an eye on the robots in case they try anything”. He should have known resistance is futile. During Mr Obama’s presidency, IBM’s Watson has proved computers can outfox the most agile minds, drones have become America’s weapon of choice, the driverless car is now a reality and the word “app” has been detached from its origin. No longer the realm of science fiction, the rise of robots now poses the central economic dilemma of the Obama era.

With each month, the US economy becomes steadily more automated. In January the US economy added just 4,000 manufacturing jobs, and the net increase since July is zero. Yet last month, manufacturing activity rose by its fastest rate since April, according to the Institute for Supply Management. The difference boils down to robots, which pose an increasingly nagging paradox: the more there are, the better for overall growth (since they boost productivity); yet the worse things become for the middle class. US median income has fallen in each of the last five years.

Things cannot continue as they are. Yet change is speeding up. Manufacturing employment is shrinking around the world. Among other countries, China is moving even faster towards industrial robotics, an area in which German and Japanese manufacturers dominate. Last year Foxconn, the Shenzhen-based assembler for Apple, Nokia and others, said it was buying 1m robots in the next three years to substitute for workers performing repetitive manual tasks. At the other end of the spectrum, a restaurant in Harbin, northern China, last year became the first to be entirely waited on by robots. Last month, China opened the world’s first museum of 3D printing.

The potential is huge. But in the developed world, the distribution of the benefits is unsustainable. The bulk of US jobs growth since mid-2009 has been in low-skilled areas, such as food preparation and domestic aides. In the second place is jobs growth in high-end services. Middle income jobs have cratered. According to the National Employment Law Project, low wage jobs (that pay between $7.69 and $13.83 an hour) formed 22 per cent of job losses in the recession but 58 per cent of recovery jobs since then – a mirror image of the picture for middle income jobs ($13.84 to $21.18).

Unsurprisingly, people are reverting to borrowing to stay in the game. Last week, Hero Wallet, a financial advisory firm, showed that one in four US workers were dipping into their retirement funds to meet current spending needs – in spite of the penalties that accrue. This usually involves taking out loans against their retirement accounts. The median income is almost 9 per cent lower today than when Mr Obama took office. It is unclear what he can do to prevent it from falling further, even if the US returns to a higher rate of economic growth.

The effects of technology are only just beginning to be felt in education and healthcare – the two most labour-intensive areas of the US economy that both suffer from productivity stagnation. Online education is beginning to spread. The mid-level private universities do not know what is about to hit them.

Even in healthcare, which reliably added jobs when every other sector was shedding them, technology is starting to look labour-saving.

But the spread of the robots will leave a large and growing chunk of the US labour force in the lurch. In their excellent primer, Race Against The Machine , Erik Brynjolfsson and Andrew McAfee point out that in the contest between changing technology and education, the former is winning. Too few Americans are prepared. Some, such as Mr Cowen, fear many never will be. He believes the federal government should pay a basic guaranteed income to all Americans – a despairing view that accepts there will be permanent losers.

Mr Obama is more optimistic. In his first term, he set a target that the US should graduate every American by 2020. Even if that were possible, it may not be a panacea. Incomes for those with only a college degree have also stagnated since 2000 (and fallen for men). Yet a healthy economy cannot for long be upheld by a minority of its workforce.

At some point, policy makers will be forced to grapple with what is intuitively obvious – that sustained growth is inconsistent with declining middle class incomes. In their book, Brynjolfsson and McAfee cite a meeting between Henry Ford and Walter Reuther, the union leader. Pointing at his new robots, Mr Ford says, “How will you get union dues from them?” Mr Reuther replied: “How will you get them to buy your cars?” – FT

Smoking ‘rots’ brain

Smoking “rots” the brain by damaging memory, learning and reasoning, according to researchers at King’s College London.

A study of 8,800 people over 50 showed high blood pressure and being overweight also seemed to affect the brain, but to a lesser extent.

Scientists involved said people needed to be aware that lifestyles could damage the mind as well as the body.

Their study was published in the journal Age and Ageing.

Researchers at King’s were investigating links between the likelihood of a heart attack or stroke and the state of the brain.

Data about the health and lifestyle of a group of over-50s was collected and brain tests, such as making participants learn new words or name as many animals as they could in a minute, were also performed.

They were all tested again after four and then eight years.

The results showed that the overall risk of a heart attack or stroke was “significantly associated with cognitive decline” with those at the highest risk showing the greatest decline.

It also said there was a “consistent association” between smoking and lower scores in the tests.

One of the researchers, Dr Alex Dregan, said: “Cognitive decline becomes more common with ageing and for an increasing number of people interferes with daily functioning and well-being.

“We have identified a number of risk factors which could be associated with accelerated cognitive decline, all of which, could be modifiable.”

Dr Simon Ridley, from Alzheimer’s Research UK, said: “Research has repeatedly linked smoking and high blood pressure to a greater risk of cognitive decline and dementia, and this study adds further weight to that evidence.

“Cognitive decline as we age can develop into dementia, and unravelling the factors that are linked to this decline could be crucial for finding ways to prevent the condition.

“These results underline the importance of looking after your cardiovascular health from mid-life.”

The Alzheimer’s Society said: “We all know smoking, a high blood pressure, high cholesterol levels and a high BMI [Body Mass Index] is bad for our heart. This research adds to the huge amount of evidence that also suggests they can be bad for our head too.

“One in three people over 65 will develop dementia but there are things people can do to reduce their risk. – BBC

Africans first in penis size

The scientific journal Personality and Individual Differences has recently published research on the average erect penis lengths of men around the world, and according to the study, the men of the Republic of Congo are the biggest at an average penis length of 18 cm.

The study ranked 113 nationalities.

British men were ranked 78th with an average length of 13.9 cm, and Americans were behind the Brits (and the Canadians, Spaniards, French, Australians and Russians,) at 12.9 cm.

By continent, African men were found to have the largest penises, while north-east Asians are the smallest.

Among European countries, the men of Iceland were deemed the biggest.

North Korean men fell short, with the average being 9.6 cm.

The research was carried out by Dr Richard Lynn, Emeritus Professor of Psychology at Ulster University.

Though the study may have peaked people’s interest, it’s raised many eyebrows too with critics claiming that the study is flawed, as he used some data from websites.

Although the recent survey plays directly into ethnic stereotypes, sexuality researchers Masters and Johnson explained that penis size really has no effect on female satisfaction, according to The Inquisitor.

The Telegraph reported that Professor of methodology at Holland’s Tilburg University Jelte Wicherts said: “This is a brave paper in a controversial area but the data has no methodology.”

Medical Daily says penis size seems to be a bit of a preoccupation for men, causing a healthy industry that claims to have various methods of enlarging the male organ. There is a significant number of men who claim to have small penises but are in fact quite normally endowed, the report says.

It says penile enhancements can come with a host of complications and side effects.

Here are a few of the average penis sizes by country in centimetres:

Republic of Congo, 18
Ecuador, 17.7
Ghana, 17.2
Colombia 17
Iceland 16.5
Italy 15.7
South Africa 15.2
Sweden 14.9
Greece 14.7
Germany 14.4
New Zealand 13.9
UK 13.9
Canada 13.9
Spain 13.9
France 13.4
Australia 13.2
Russia 13.2
USA 12.9
Ireland 12.7
Romania 12.7
China 10.9
India 10
Thailand 10
South Korea 9.6
North Korea 9.6

Curiosity lands successfully on Mars

The most high-tech Mars rover ever built has landed on the red planet.

NASA says it received a signal from the Curiosity rover Sunday night after a plunge through the Martian atmosphere described as “seven minutes of terror.”

The rover is the size of a small car, so engineers had to come up with a new way to set it down. For the first time, cables were used to lower the rover inside of a giant crater.

At $2.5 billion, it’s the most ambitious and priciest Mars mission yet. For the next two years, the rover will drill into rocks and scoop up soil. It will be exploring whether the planet’s environment could have supported life in the form of microscopic organisms.

The Curiosity rover survived a harrowing landing on Mars early Monday in a never-before-tried technique that saw it lowered to the surface of the Red Planet like a spider on a string, the US space agency said. – DPA

Obesity affected by surrounding race groups

The racial and ethnic composition of a community is associated with the obesity risk of individuals living within the community, according to a study led by researchers at the Agency for Healthcare Research and Quality (AHRQ) and the Johns Hopkins Bloomberg School of Public Health. The findings, published in the June 14 edition of the American Journal of Public Health, may help explain disparities in obesity rates among racial groups and point to some of the environmental factors that may contribute to obesity in the United States.

For the study, the researchers analyzed data from the Medical Expenditure Panel Survey, which represented a cross-section of the U.S. population. The data were matched with geographical information from the U.S. Census. Obesity was calculated based on each study participant’s body mass index (BMI), a measure of weight in relation to height.

Analysis of the data found that community ethnic composition might affect residents’ likelihood of being obese, and the effect varied by the residents’ own ethnicity, for example, living in a community with a Hispanic population of 25 percent or greater was associated with 21 percent higher odds for obesity for Hispanics in that community. Non-Hispanic whites had 23 percent higher odds for obesity living in the same community.

The opposite was true for communities with high concentrations of non-Hispanic Asians. In those communities, the odds for obesity were 28 percent lower for non-Hispanic whites in those communities. While non-Hispanic blacks have the highest rates of obesity in U.S., living in a community with a high concentration of non-Hispanic blacks did not raise the odds of obesity even among non-Hispanic blacks.

“Obesity is one of the nation’s most pressing health problems, and our findings suggest that community characteristics related to racial and ethnic composition may have an important effect on residents’ weight,” said James B. Kirby, PhD, of the Agency for Healthcare Research and Quality, who was the lead author of the study. “This study will enhance understanding of the disparities in the U.S. obesity epidemic and how certain racial and ethnic minorities are disproportionately affected.”

“Social and built environments play an important role in influencing individuals’ health outcomes including obesity. Future research needs to better understand the mechanisms, but clearly interventions are needed to reduce obesity disparities in the United States,” said Youfa Wang, MD, PhD, MS, coauthor of the study and director of the Johns Hopkins Global Center on Childhood Obesity and Associate Professor at the Bloomberg School of Public Health.

Source: redOrbit (http://s.tt/1g8TE)

Heart drug could treat racism – new experiment

A common heart disease drug may have the unusual side-effect of combating racism, a new study suggests.

White volunteers given the beta-blocker, used to treat chest pains and lower heart rates, scored lower on a standard psychological test of “implicit” racist attitudes.

They appeared to be less racially prejudiced at a subconscious level than another group treated with a “dummy” placebo pill.

Scientists believe the discovery can be explained by the fact that racism is fundamentally founded on fear.

Propranolol acts both on nerve circuits that govern automatic functions such as heart rate, and the part of the brain involved in fear and emotional responses. The drug is also used to treat anxiety and panic.

Experimental psychologist Dr Sylvia Terbeck, from Oxford University, who led the study published in the journal Psychopharmacology, said: “Our results offer new evidence about the processes in the brain that shape implicit racial bias.

“Implicit racial bias can occur even in people with a sincere belief in equality. Given the key role that such implicit attitudes appear to play in discrimination against other ethnic groups, and the widespread use of propranolol for medical purposes, our findings are also of considerable ethical interest.”

Two groups of 18 participants took part in the study. Each volunteer was asked to undertake a “racial Implicit Association Test” (IAT) one to two hours after taking propranolol or the placebo.

The test involved categorising positive and negative words, and pictures of black and white individuals, on a computer screen.

Differences in the time taken to carry out the tasks provided the basis of the result.

More than a third of the volunteers had a “negative” IAT score, meaning they were biased towards being non-racist at a subconscious level. This was not seen in any member of the placebo group.

Propranolol had no effect on a different measure of “explicit” racial prejudice, religious and sexual prejudice, or prejudice against drug addicts.

These were tested using a “feeling thermometer” psychological tool used for assessing explicit prejudice. Volunteers were asked to rate how “warm” they felt towards different groups on a 10-point scale analogous to a thermometer.

The scientists wrote: “The main finding of our study is that propranolol significantly reduced implicit but not explicit racial bias.”

Despite the study’s small size and limitations, the researchers believe it raises important ethical and philosophical questions.

Co-author Professor Julian Savulescu, from Oxford University’s Faculty of Philosophy, said: “Such research raises the tantalising possibility that our unconscious racial attitudes could be modulated using drugs, a possibility that requires careful ethical analysis.

“Biological research aiming to make people morally better has a dark history. And propranolol is not a pill to cure racism. But given that many people are already using drugs like propranolol which have ‘moral’ side effects, we at least need to better understand what these effects are.”

But Dr Chris Chambers, from the University of Cardiff’s School of Psychology, said the results should be viewed with “extreme caution”.

He said: “We don’t know whether the drug influenced racial attitudes only or whether it altered implicit brain systems more generally.

“And we can’t rule out the possibility that the effects were due to the drug incidentally reducing heart rate. So although interesting, in my view these preliminary results are a long way from suggesting that propranolol specifically influences racial attitudes.”

Dinosaurs had fleas too – giant ones, fossils show

By Seth Borenstein
AP Science Writer

WASHINGTON (AP) — In the Jurassic era, even the flea was a beast, compared to its minuscule modern descendants. These pesky bloodsuckers were nearly an inch long.

New fossils found in China are evidence of the oldest fleas – from 125 million to 165 million years ago, said Diying Huang of the Nanjing Institute of Geology and Paleontology. Their disproportionately long proboscis, or straw-like mouth, had sharp weapon-like serrated edges that helped them bite and feed from their super-sized hosts, he and other researchers reported Wednesday in the journal Nature.

Scientists figure about eight or more of today’s fleas would fit on the burly back of their ancient ancestor.

“That’s a beast,” said study co-author Michael Engel, entomology curator at the Natural History Museum at the University of Kansas. “It was a big critter. I can’t even imagine coming home and finding my miniature schnauzer with one or more of these things crawling around on it.”

The ancient female fleas were close to twice the size of the males, researchers found, which fits with modern fleas.

But Engel said it’s not just the size that was impressive about the nine flea fossils. It was their fearsome beak capable of sticking into and sucking blood from the hides of certain dinosaurs, probably those that had feathers.

These flea beaks “had almost like a saw running down the side,” Engel said. “This thing was packing a weapon. They were equipped to dig into something.”

While the ancient fleas were big, they had one disadvantage compared to modern ones: Their legs weren’t too developed. Evolving over time, fleas went from crawling to jumping, Huang said.

“Luckily for the land animals of the Mesozoic, these big flat fleas lacked the tremendous jumping capacity that our common fleas have,” said Joe Hannibal of the Cleveland Museum of Natural History. He wasn’t involved in the study, but praised it as useful and interesting.

Just finding the fleas was a stroke of luck, Huang said. He first found one in a Chinese fossil market and mentioned it to someone at his hotel. The other guest showed him a photo of another fossilized flea, telling him it was from Daohugou in northeastern China, where there’s a famous fossil bed from about 165 million years ago. Huang went there and found fleas preserved in a brownish film of volcanic ash. The grains of rock were so fine you could see antennae and other details of the fleas, he said.

Modern fleas get engorged after they feast on blood, but these didn’t seem engorged, Engel said.

It shouldn’t seem too surprising that there were large fleas more than 100 million years ago. If you go back even farther in time, ancestors of dragonflies and damsel flies had 3-foot wingspans, Engel said.

—

Online:

Nature: http://www.nature.com/nature

‘Africans are less intelligent than Westerners’

One of the world’s most eminent scientists was embroiled in an extraordinary row last night after he claimed that black people were less intelligent than white people and the idea that “equal powers of reason” were shared across racial groups was a delusion.

James Watson, a Nobel Prize winner for his part in the unravelling of DNA who now runs one of America’s leading scientific research institutions, drew widespread condemnation for comments he made ahead of his arrival in Britain today for a speaking tour at venues including the Science Museum in London.

The 79-year-old geneticist reopened the explosive debate about race and science in a newspaper interview in which he said Western policies towards African countries were wrongly based on an assumption that black people were as clever as their white counterparts when “testing” suggested the contrary. He claimed genes responsible for creating differences in human intelligence could be found within a decade.

The newly formed Equality and Human Rights Commission, successor to the Commission for Racial Equality, said it was studying Dr Watson’s remarks ” in full”. Dr Watson told The Sunday Times that he was “inherently gloomy about the prospect of Africa” because “all our social policies are based on the fact that their intelligence is the same as ours – whereas all the testing says not really”. He said there was a natural desire that all human beings should be equal but “people who have to deal with black employees find this not true”.

His views are also reflected in a book published next week, in which he writes: “There is no firm reason to anticipate that the intellectual capacities of peoples geographically separated in their evolution should prove to have evolved identically. Our wanting to reserve equal powers of reason as some universal heritage of humanity will not be enough to make it so.”

The furore echoes the controversy created in the 1990s by The Bell Curve, a book co-authored by the American political scientist Charles Murray, which suggested differences in IQ were genetic and discussed the implications of a racial divide in intelligence. The work was heavily criticised across the world, in particular by leading scientists who described it as a work of ” scientific racism”.

Dr Watson arrives in Britain today for a speaking tour to publicise his latest book, Avoid Boring People: Lessons from a Life in Science. Among his first engagements is a speech to an audience at the Science Museum organised by the Dana Centre, which held a discussion last night on the history of scientific racism.

Critics of Dr Watson said there should be a robust response to his views across the spheres of politics and science. Keith Vaz, the Labour chairman of the Home Affairs Select Committee, said: “It is sad to see a scientist of such achievement making such baseless, unscientific and extremely offensive comments. I am sure the scientific community will roundly reject what appear to be Dr Watson’s personal prejudices.

“These comments serve as a reminder of the attitudes which can still exists at the highest professional levels.”

The American scientist earned a place in the history of great scientific breakthroughs of the 20th century when he worked at the University of Cambridge in the 1950s and 1960s and formed part of the team which discovered the structure of DNA. He shared the 1962 Nobel Prize for medicine with his British colleague Francis Crick and New Zealand-born Maurice Wilkins.

But despite serving for 50 years as a director of the Cold Spring Harbor Laboratory on Long Island, considered a world leader in research into cancer and genetics, Dr Watson has frequently courted controversy with some of his views on politics, sexuality and race. The respected journal Science wrote in 1990: “To many in the scientific community, Watson has long been something of a wild man, and his colleagues tend to hold their collective breath whenever he veers from the script.”

In 1997, he told a British newspaper that a woman should have the right to abort her unborn child if tests could determine it would be homosexual. He later insisted he was talking about a “hypothetical” choice which could never be applied. He has also suggested a link between skin colour and sex drive, positing the theory that black people have higher libidos, and argued in favour of genetic screening and engineering on the basis that ” stupidity” could one day be cured. He has claimed that beauty could be genetically manufactured, saying: “People say it would be terrible if we made all girls pretty. I think it would be great.”

The Cold Spring Harbor Laboratory said yesterday that Dr Watson could not be contacted to comment on his remarks.

Steven Rose, a professor of biological sciences at the Open University and a founder member of the Society for Social Responsibility in Science, said: ” This is Watson at his most scandalous. He has said similar things about women before but I have never heard him get into this racist terrain. If he knew the literature in the subject he would know he was out of his depth scientifically, quite apart from socially and politically.”

Anti-racism campaigners called for Dr Watson’s remarks to be looked at in the context of racial hatred laws. A spokesman for the 1990 Trust, a black human rights group, said: “It is astonishing that a man of such distinction should make comments that seem to perpetuate racism in this way. It amounts to fuelling bigotry and we would like it to be looked at for grounds of legal complaint.”

Postscript: A week after this report was published in 2007, Professor Watson was forced to retire from this post amid an international scandal over his remarks. According to him, “I turned against the left wing because they don’t like genetics, because genetics implies that sometimes in life we fail because we have bad genes. They want all failure in life to be due to the evil system.”