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Modern humans evolved in Africa around 200 thousand years ago (kya), and have lived continuously on the African continent longer than in any other geographic region. Africa not only has the highest levels of human genetic variation in the world but also contains a considerable amount of linguistic, environmental and cultural diversity. For example, more than 2000 distinct ethno-linguistic groups, representing nearly a third of the world's languages, currently exist in Africa (http://www.ethnologue.com/) (Figure 1). Africans live in a wide range of environments, such as deserts, tropical rainforests, savannas, swamps, and mountain highlands [1,2]. Furthermore, some of these environments have undergone dramatic changes over the course of modern human evolution [1,3,4]. African populations also practice a wide array of subsistence strategies, including various forms of hunting-gathering, agriculture and pastoralism, across the continent perhaps in response to this environmental variability over time and geographic space. African demographic history has consisted of fluctuations in population size, short- and long- range migration, admixture and extensive population structure which have resulted in complex patterns of variation in modern populations [1,5]. The timing and duration of some of these demographic events were often correlated with known major environmental changes and/or cultural developments in Africa [6]. A number of novel genetic and phenotypic adaptations have also evolved in Africans in response to dramatic variation in environment, diet, and exposure to infectious disease across the continent. In some cases, these adaptations have occurred in the last several thousand years, exemplifying the ongoing evolution of human populations. Thus, present-day patterns of variation in African genomes are a product of both demographic and selective events. The characterization of extant genetic diversity in Africa will be critical for reconstructing modern human origins and African demographic history. In addition, this genetic information, together with phenotype data on variable traits, will be informative for identifying population-specific variants that play a role in gene function, phenotypic adaptation and complex disease susceptibility in Africans and populations of African descent. Evolutionary History of Modern Humans in Africa Current paleontological data suggest that the transition to anatomically modern Homo sapiens occurred in Africa, supporting the ‘Recent African Origin’ model of human evolution (Figure 2). The earliest known suite of derived traits associated with anatomically modern humans was identified in fossil remains from East Africa dated to around 195–150 kya [7,8,9]. Thus, the basic morphology of modern humans was established in Africa about 200 kya [10]. Other early anatomically modern humans, with a more full set of modern features, also appear in Africa before 100 kya and in the Near East around 100 kya [11,12,13], followed by the more recent expansion of anatomically modern humans into Eurasia within the past 40,000–80,000 years [1,2] (Figure 2). Although the mode of evolution is still unclear, it has been suggested that the emergence of modern humans was not a sudden event, but rather a continuous process of gradual morphological change from archaic to modern H. sapiens[11]. However, it has also been argued that modern human origins likely involved episodes of sudden morphological change, leading to the appearance of anatomically modern H. sapiens as a species distinct from archaic humans [14]. Regardless of the mode of evolution, current fossil and chronological evidence indicate that modern humans existed in Africa for a relatively long period of time before their migration across much of the globe. Read the rest of the article ► ► Source: Current Biology
By Steve Vickers The Lemba people of Zimbabwe and South Africa may look like their compatriots, but they follow a very different set of customs and traditions. They do not eat pork, they practise male circumcision, they ritually slaughter their animals, some of their men wear skull caps and they put the Star of David on their gravestones. Their oral traditions claim that their ancestors were Jews who fled the Holy Land about 2,500 years ago. It may sound like another myth of a lost tribe of Israel, but British scientists have carried out DNA tests which have confirmed their Semitic origin. These tests back up the group's belief that a group of perhaps seven men married African women and settled on the continent. The Lemba, who number perhaps 80,000, live in central Zimbabwe and the north of South Africa. And they also have a prized religious artefact that they say connects them to their Jewish ancestry - a replica of the Biblical Ark of the Covenant known as the ngoma lungundu, meaning "the drum that thunders". The object went on display recently at a Harare museum to much fanfare, and instilled pride in many of the Lemba. "For me it's the starting point," says religious singer Fungisai Zvakavapano-Mashavave. "Very few people knew about us and this is the time to come out. I'm very proud to realise that we have a rich culture and I'm proud to be a Lemba. "We have been a very secretive people, because we believe we are a special people." Religion vs culture The Lemba have many customs and regulations that tally with Jewish tradition. They wear skull caps, practise circumcision, which is not a tradition for most Zimbabweans, avoid eating pork and food with animal blood, and have 12 tribes. “ Many people say that the story is far-fetched, but the oral traditions of the Lemba have been backed up by science ” They slaughter animals in the same way as Jewish people, and they put the Jewish Star of David on their tombstones. Members of the priestly clan of the Lemba, known as the Buba, were even discovered to have a genetic element also found among the Jewish priestly line. "This was amazing," said Prof Tudor Parfitt, from the University of London. "It looks as if the Jewish priesthood continued in the West by people called Cohen, and in same way it was continued by the priestly clan of the Lemba. "They have a common ancestor who geneticists say lived about 3,000 years ago somewhere in north Arabia, which is the time of Moses and Aaron when the Jewish priesthood started." Prof Parfitt is a world-renowned expert, having spent 20 years researching the Lemba, and living with them for six months. The Lemba have a sacred prayer language which is a mixture of Hebrew and Arabic, pointing to their roots in Israel and Yemen. Despite their ties to Judaism, many of the Lemba in Zimbabwe are Christians, while some are Muslims. "Christianity is my religion, and Judaism is my culture," explains Perez Hamandishe, a pastor and member of parliament from the Movement for Democratic Change (MDC). Despite their centuries-old traditions, some younger Lemba are taking a more liberal view. "In the old days you didn't marry a non-Lemba, but these days we interact with others," says Alex Makotore, son of the late Chief Mposi from the Lemba "headquarters" in Mberengwa. "I feel special in my heart but not in front of others such that I'm separated from them. Culture is dynamic." Crowds The oral traditions of the Lemba say that the ngoma lungundu is the Biblical wooden Ark made by Moses, and that centuries ago a small group of men began a long journey carrying it from Yemen to southern Africa. “ Hearing from those professors in Harare and seeing the ngoma makes it clear that we are a great people and I'm very proud ” The object went missing during the 1970s and was eventually rediscovered in Harare in 2007 by Prof Parfitt. "Many people say that the story is far-fetched, but the oral traditions of the Lemba have been backed up by science," he says. Carbon dating shows the ngoma to be nearly 700 years old - pretty ancient, if not as old as Bible stories would suggest. But Prof Parfitt says this is because the ngoma was used in battles, and would explode and be rebuilt. The ngoma now on display was a replica, he says, possibly built from the remains of the original. "So it's the closest descendant of the Ark that we know of," Prof Parfitt says. Large crowds came to see the unveiling of the ngoma and to attend lectures on the identity of the Lemba. For David Maramwidze, an elder in his village, the discovery of the ngoma has been a defining moment. "Hearing from those professors in Harare and seeing the ngoma makes it clear that we are a great people and I'm very proud," he says. "I heard about it all my life and it was hard for me to believe, because I had no idea of what it really is. "I'm still seeing the picture of the ngoma in my mind and it will never come out from my brain. Now we want it to be given back to the Lemba people." Source: BBC News
March 11, 2010 Lindon, UT In order to encourage more people to find their ancestors and connect with family, Footnote.com, the web's premier interactive history site, is opening all of their U.S. census documents for free to the public for a limited time. Unlike any other historical collection on the web, the Interactive Census Collection has the unique ability to connect people related to ancestors found on the historical documents. Simply by clicking the "I'm Related" button for a name on the document will identify you as a descendant and also list others that have done the same. Never before has it been as easy to connect with distant relatives through historical documents. To learn how to get started with the Interactive Census, visit: http://go.footnote.com/discover. Finding a record featuring an ancestor's name provides not only an emotional experience but also a connection with the past. On Footnote.com it's more than just finding a name on a census record. Interactive tools allow people to enhance the documents by adding their own contributions including: "TV programs including 'Who Do You Think You Are?' on NBC and 'Faces of America' on PBS will surely increase the interest in family history in the United States," explains Russell Wilding, CEO of Footnote.com. "We believe that using our Interactive Census Collection is a great way for those who are new to genealogy to get started." In addition to providing the basic information about ancestors with the census documents, Footnote.com has been working with the National Archives and other institutions to digitize and index over 63 million historical records that include: "Using the records on Footnote to go beyond the names and dates is like adding color to your tree," says Roger Bell, Footnote's Senior Vice President of Content and Product. "The more details you add, the more colorful your family tree becomes." To search for an ancestor and experience family history like never before, visit: http://go.footnote.com/discover. Source: Footnote.com
Profile America for the 24th day of Black History Month. Rita Dove is among the nation's most recognized African-American poets. She was the youngest person and the first black to serve as Poet Laureate of the United States. Her most widely known work is "Thomas and Beulah," a collection of poems telling the story of her grandparents, for which she won a Pulitzer Prize. Rita Dove has been a professor of English at the University of Virginia since 1993. In the U.S. today, there are nearly 1.3 million college professors and instructors, 46 percent of them women and 6 percent African-American. Sources: www.poets.org Statistical Abstract of the United States 2009, t. 596 Source: U.S. Census Bureau
Audio: http://www.census.gov/multimedia/www/radio/black_history_month/black-21.php Profile America for the 21st day of Black History Month. Sam Gilliam is widely recognized as one of the foremost contemporary African-American artists, whose work reflects the school of art known as color field painting. Inspired by laundry hanging outside his studio, he was the first artist to champion displaying paintings as draped objects rather than attached to a frame. One of Gilliam's works hangs in the Census Bureau building in Suitland, Maryland -- one of the most dramatic new federal office buildings in the country. In the U.S., there are 227,000 artists along with those who work in the art community, just over 2½ percent of them African-American. Sources: www.rogallery.com Statistical Abstract of the United States 2009, t. 596
Profile America for the 18th day of Black History Month. Bessie Coleman picked cotton to help support her family and finished high school by studying on her own. Her dream was to fly but no flying school would accept her because of her gender and race. So she learned French and went to France, where she earned her International Flying License, making her the only licensed black woman pilot in the world. Bessie Coleman died in a crash while practicing for an air show in 1926 -- her controls jammed by a loose hand tool. There are 123,000 pilots and flight engineers in the U.S., slightly more than 4 percent female and less than 1 percent African-American. Sources: U.S. Centennial of Flight Commission Statistical Abstract of the United States 2009, t. 596 Source: U.S. Census Bureau
NEW YORK — Scientists who decoded the DNA of some southern Africans have found striking new evidence of the genetic diversity on that continent, and uncovered a surprise about the ancestry of Archbishop Desmond Tutu. They found, for example, that any two Bushmen in their study who spoke different languages were more different genetically than a European compared to an Asian. That was true even if the Bushmen lived within walking distance of each other. "If we really want to understand human diversity, we need to go to (southern) Africa and we need to study those people," said Stephan Schuster of Pennsylvania State University. He's an author of the study, which appears in Thursday's issue of the journal Nature. The study also found 1.3 million tiny variations that hadn't been observed before in any human DNA. That should help scientists sort out whether particular genes promote certain diseases or influence a person's response to medications. Findings like that could have payoffs both within Africa and elsewhere, experts said. The genetic diversity of Africa's population is no surprise to scientists. Modern humans evolved on that continent about 200,000 years ago and have lived there longer than anyplace else. So that's where they've had the most time to develop genetic differences. The varied environments of Africa have also encouraged genetic differences. Africa was the ancient source of modern humans worldwide, so "we're looking really back into the wellspring of our genetic origins here," said Richard Gibbs, a study author from the Baylor College of Medicine in Houston. The study focused on genomes, a person's complete collection of DNA. The researchers decoded genomes of a Kalahari Desert bushman and of Tutu, the 1984 Nobel Peace laureate and former head of the Anglican Church of Southern Africa. They also decoded partial genomes from three other Bushmen. Tutu was included to represent a Bantu ancestry, in contrast to Bushmen. Bantu people have a tradition of farming, while Bushmen are longtime hunter-gatherers who represent the oldest known lineage of modern humans. But when researchers looked at Tutu's genome, they found surprising evidence that his mother's ancestry includes at least one Bushman woman. It's not clear how many generations back that woman lived. Tutu told The Associated Press that discovering he is related to "these wise people" made him feel "very privileged and blessed." While the study found many previously unknown DNA variations in Tutu's genome and especially the Bushman DNA, it's important to remember that overall, the genomes of any two people are virtually identical. The differences tracked in the new study lie in individual "letters" of the 3 billion-letter genetic sequence. "We are all very, very similar to one another," Schuster said. Gibbs said the DNA differences discovered in the African subjects can't be used to support racist arguments. He noted that DNA diversity within a continent is greater than the differences between continents. The study found, in fact, that Bushmen are as different from a previously studied Yoruba man in Nigeria as a European man is. The new work "is a great start" toward more genome-decoding studies in Africa, said Sarah Tishkoff of the University of Pennsylvania. More studies are needed to get a fuller picture of the continent's diversity, said Tishkoff, who studies that topic. Source: Associated Press
Sometime around the middle of April 1804, a slave named John Freeman wrote a letter to the president of the United States. Freeman, technically owned by a Maryland doctor, William Baker, had been contracted to work for Thomas Jefferson, who engaged him to serve in the White House and accompany Jefferson on trips to Monticello. Now, Freeman was writing because he wanted the president to buy him outright. "I am sorye to trubel you with a thing of this kind," he began, saying he felt obliged to do so because "I have been foolish anufe to in gage myself to Melindar." The letter was an extraordinary feat of persuasion, heartfelt but also artful. Freeman, promising to serve Jefferson faithfully, went on to ask whether the president might even be "so good as to keep us [both]" -- that is, purchase a female slave named Melinda Colbert. On their trips to Virginia, Freeman had become enamored of Colbert, a niece of Sally Hemings who belonged to Jefferson's daughter Maria and her husband. Maria died that month, and the two slaves feared Melinda would be sold away. The letter was one among numerous acts of resourcefulness and initiative that would result, years later, in John Freeman's being purchased and owned by not one U.S. president, but two. He would marry his beloved Melinda; gain his freedom; and, not least, purchase a piece of property on K Street in Northwest Washington, between 18th and 19th streets. There Freeman would establish a home for her and their children, taking his place among a unique, now largely forgotten community of free black residents with ties to U.S. presidents such as Jefferson, James Madison and George Washington. In the ensuing years Freeman'sneighborhood became home to by a striking number of freed slaves who also had been owned by presidents. In the middle of the 19th century, the community included men and women whose start in life was about as disadvantaged as a human being's could be, but who, through drive and intellect and that classic Washington ingredient -- influential connections -- were able to improve their prospects. They would socialize together, work together and acquire property that in some cases would allow descendants to enjoy lives easier than theirs had been. "Wouldn't you like to have had a piece of property on K Street?" says Beth Taylor, an independent scholar and former director of education at Montpelier, the historic home of James Madison. While researching Madison slaves, Taylor has become fascinated by this area, once home to what she calls Washington's "first families of color." Their life stories testify to the bonds between freed blacks in antebellum Washington, and remind us that a number of early American presidents did indeed own other human beings. "As I do more research on the neighborhood, I wouldn't be at all surprised if I found descendants of slaves who worked for Tyler, Polk, Taylor, Jackson,"Taylor says. "These were all presidents, like Jefferson and Madison, who had slaves working for them in the White House." In the early days of the union, she explains, presidents needed 10 or12 people to run the domestic side of the White House. The staff was often a mix of whites, free blacks and slaves, some from their own plantations, some purchased in the city and some, like Freeman, hired from other masters. "One aspect of it that always strikes me is how these statesmen . . . had a real tendency to talk about the slavery problem, the slavery issue," Taylor reflects. "There was this lack of understanding on their part. . . . This is not the slavery problem. These are people enslaved." Read the rest of the story ► ► Source: Washington Post
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