New research proves single origin of humans in Africa

July 18, 2007

New research published in the journal Nature (19 July) has proved the single origin of humans theory by combining studies of global genetic variations in humans with skull measurements across the world. The research, at the University of Cambridge and funded by the Biotechnology and Biological Sciences Research Council (BBSRC), represents a final blow for supporters of a multiple origins of humans theory.

Competing theories on the origins of anatomically modern humans claim that either humans originated from a single point in Africa and migrated across the world, or different populations independently evolved from homo erectus to home sapiens in different areas.

The Cambridge researchers studied genetic diversity of human populations around the world and measurements of over 6,000 skulls from across the globe in academic collections. Their research knocks down one of the last arguments in favour of multiple origins. The new findings show that a loss in genetic diversity the further a population is from Africa is mirrored by a loss in variation in physical attributes.

Lead researcher, Dr Andrea Manica from the University's Department of Zoology, explained: "The origin of anatomically modern humans has been the focus of much heated debate. Our genetic research shows the further modern humans have migrated from Africa the more genetic diversity has been lost within a population.

"However, some have used skull data to argue that modern humans originated in multiple spots around the world. We have combined our genetic data with new measurements of a large sample of skulls to show definitively that modern humans originated from a single area in Sub-saharan Africa."

The research team found that genetic diversity decreased in populations the further away from Africa they were - a result of 'bottlenecks' or events that temporarily reduced populations during human migration. They then studied an exceptionally large sample of human skulls. Taking a set of measurements across all the skulls the team showed that not only was variation highest amongst the sample from south eastern Africa but that it did decrease at the same rate as the genetic data the further the skull was away from Africa.

To ensure the validity of their single origin evidence the researchers attempted to use their data to find non-African origins for modern humans. Research Dr Francois Balloux explains: "To test the alternative theory for the origin of modern humans we tried to find an additional, non-African origin. We found this just did not work. Our findings show that humans originated in a single area in Sub-Saharan Africa."
-end-


Biotechnology and Biological Sciences Research Council

Related Genetic Diversity Articles from Brightsurf:

In the Cerrado, topography explains the genetic diversity of amphibians more than land cover
Study shows that a tree frog endemic to a mountainous region of the Brazilian savanna is unable to disperse and find genetically closer mates when the terrain is rugged, potentially endangering survival of the species

New DNA sequencing technique may help unravel genetic diversity of cancer tumors
Understanding the genetic diversity of individual cells within a cancer tumor and how that might impact the disease progression has remained a challenge, due to the current limitations of genomic sequencing.

Researchers uncover the arks of genetic diversity in terrestrial mammals
Mapping the distribution of life on Earth, from genes to species to ecosystems, is essential in informing conservation policies and protecting biodiversity.

Seahorse and pipefish study by CCNY opens window to marine genetic diversity May 08, 2020
The direction of ocean currents can determine the direction of gene flow in rafting species, but this depends on species traits that allow for rafting propensity.

Study helps arboreta, botanical gardens meet genetic diversity conservation goals
In a groundbreaking study, an international team of 21 scientists evaluated five genera spanning the plant tree of life (Hibiscus, Magnolia, Pseudophoenix, Quercus and Zamia) to understand how much genetic diversity currently exists in collections in botanical gardens and arboreta worldwide.

Study reveals rich genetic diversity of Vietnam
In a new paper, Dang Liu, Mark Stoneking and colleagues have analyzed newly generated genome-wide SNP data for the Kinh and 21 additional ethnic groups in Vietnam, encompassing all five major language families in MSEA, along with previously published data from nearby populations and ancient samples.

Coastal pollution reduces genetic diversity of corals, reef resilience
A new study by researchers at the University of Hawai'i at Mānoa School of Ocean and Earth Science and Technology found that human-induced environmental stressors have a large effect on the genetic composition of coral reef populations in Hawai'i.

New world map of fish genetic diversity
An international research team from ETH Zurich and French universities has studied genetic diversity among fish around the world for the first time.

Texas A&M study reveals domestic horse breed has third-lowest genetic diversity
A new study by Dr. Gus Cothran, professor emeritus at the Texas A&M School of Veterinary Medicine & Biomedical Sciences, has found that the Cleveland Bay horse breed has the third-lowest genetic variation level of domestic horses, ranking above only the notoriously inbred Friesian and Clydesdale breeds.

Genetic diversity facilitates cancer therapy
Cancer patients with more different HLA genes respond better to treatment.

Read More: Genetic Diversity News and Genetic Diversity Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.