Featured Research

from universities, journals, and other organizations

Founding Fathers & Mothers: How Many Crossed The Land Bridge?

Date:
May 24, 2005
Source:
Rutgers, the State University of New Jersey
Summary:
For the first time, we have a realistic estimate of how many ancients made that ice age trek across the long-lost land bridge from Asia to become the first Native Americans. Jody Hey, a professor of genetics at Rutgers, The State University of New Jersey, has developed a computational method that uses genetic information to create models of population divergence -- where a group has split off from its ancestral population to pursue its own destiny.

NEW BRUNSWICK/PISCATAWAY, N.J. -- Programs on the Discovery Channel and PBS have sparked fresh interest in the prehistoric peopling of the New World. Now, for the first time, we have a realistic estimate of how many ancients made that ice age trek across the long-lost land bridge from Asia to become the first Native Americans.

Jody Hey, a professor of genetics at Rutgers, The State University of New Jersey, has developed a computational method that uses genetic information to create models of population divergence -- where a group has split off from its ancestral population to pursue its own destiny.

In a paper appearing in the June 2005 issue of PLoS (Public Library of Science) Biology, Hey disclosed his findings. "The estimated effective size of the founding population for the New World is about 70 individuals," Hey said. "Calculations also showed that this represents approximately 1 percent of the effective size of the estimated ancestral Asian population."

"Effective size" in population genetics is often thought of as the number of adults of reproductive age. One rule of thumb is the effective size might be about one third of the 'census population size' which, in this case, comes out to about 200 people.

In addition to population size, Hey's rigorous and complex methodology also generated historical estimates of when the divergence occurred. His dates are consistent with much of the archaeological record -- in the range of 12,000-14,000 years ago.

He was also able to discern changes in population size and the extent of gene flow between populations, potentially representing renewed contact. Hey used nine genes in which sequences and frequencies were well documented in the scientific literature.

"The beauty of the new methodology is that it uses actual DNA sequences collected from Asian peoples and Native Americans, an approach that can provide a detailed portrait of historical populations," Hey said. The method doesn't use summary statistics or averages as some approaches do, but gleans as much information as possible directly from the genetic data.

Hey focused on the genetics of Amerind-speaking populations, one of three major language groups in the New World representing the earliest migrants who extended deep into the Americas. The other groups, the more recent Athabascan speakers and the even more recent Eskimos and Aleuts, had less comprehensive genetic information available and were not included in Hey's study.


Story Source:

The above story is based on materials provided by Rutgers, the State University of New Jersey. Note: Materials may be edited for content and length.


Cite This Page:

Share This



More Health & Medicine News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Could Even Casual Marijuana Use Alter Your Brain?

Could Even Casual Marijuana Use Alter Your Brain?

Newsy (Apr. 16, 2014) A new study conducted by researchers at Northwestern and Harvard suggests even casual marijuana use can alter your brain. Video provided by Newsy
Powered by NewsLook.com
Thousands Of Vials Of SARS Virus Go Missing

Thousands Of Vials Of SARS Virus Go Missing

Newsy (Apr. 16, 2014) A research institute in Paris somehow misplaced more than 2,000 vials of the deadly SARS virus. Video provided by Newsy
Powered by NewsLook.com
Formerly Conjoined Twins Released From Dallas Hospital

Formerly Conjoined Twins Released From Dallas Hospital

Newsy (Apr. 16, 2014) Conjoined twins Emmett and Owen Ezell were separated by doctors in August. Now, nearly nine months later, they're being released from the hospital. Video provided by Newsy
Powered by NewsLook.com
Ebola Outbreak Now Linked To 121 Deaths

Ebola Outbreak Now Linked To 121 Deaths

Newsy (Apr. 15, 2014) The ebola virus outbreak in West Africa is now linked to 121 deaths. Health officials fear the virus will continue to spread in urban areas. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins