Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Earth Science News .




ABOUT US
Monkey teeth help reveal Neanderthal weaning
by Staff Writers
Davis CA (SPX) May 27, 2013


This molar tooth model with the cut face shows color-coded barium patterns merging with a microscopic map of growth lines. (Ian Harrowell, Christine Austin and Manish Arora/graphic).

Most modern human mothers wean their babies much earlier than our closest primate relatives. But what about our extinct relatives, the Neanderthals?

A team of U.S. and Australian researchers reports in the journal Nature May 22 that they can now use fossil teeth to calculate when a Neanderthal baby was weaned. The new technique is based in part on knowledge gained from studies of teeth from human infants and from monkeys at the California National Primate Research Center at the University of California, Davis.

Using the new technique, the researchers concluded that at least one Neanderthal baby was weaned at much the same age as most modern humans.

Just as tree rings record the environment in which a tree grew, traces of barium in the layers of a primate tooth can tell the story of when an infant was exclusively milk-fed, when supplemental food started, and at what age it was weaned, said Katie Hinde, professor of human evolutionary biology at Harvard University and an affiliate scientist at the UC Davis Primate Center.

Hinde directs the Comparative Lactation Laboratory at Harvard and has conducted a three-year study of lactation, weaning and behavior among rhesus macaques at UC Davis.

The team was able to determine exact timing of birth, when the infant was fed exclusively on mother's milk, and the weaning process, from mineral traces in teeth. By studying monkey teeth and comparing them to center records, they could show that the technique was accurate almost to the day.

After validating the technique with monkeys, the scientists applied it to human teeth and a Neanderthal tooth. They found that the Neanderthal baby was fed exclusively on mother's milk for seven months, followed by seven months of supplementation - a similar pattern to present-day humans. The technique opens up extensive opportunities to further investigate lactation in fossils and museum collections of primate teeth.

Although there is some variation among human cultures, the accelerated transition to foods other than mother's milk is thought to have emerged in our ancestral history due, in part, to more cooperative infant care and access to a more nutritious diet, Hinde said. Shorter lactation periods could mean shorter gaps between pregnancies and a higher rate of reproduction. However, there has been much debate about when our ancestors evolved accelerated weaning.

For the past few decades researchers have relied on tooth eruption age as a direct proxy for weaning age. Yet recent investigations of wild chimpanzees have shown that the first molar eruption occurs toward the end of weaning.

"By applying these new techniques to primate teeth in museum collections, we can more precisely assess maternal investment across individuals within species, as well as life history evolution among species," Hinde said.

Authors in addition to Hinde were: Christine Austin and Manish Arora, Icahn School of Medicine at Mount Sinai, New York, Harvard School of Public Health, and University of Sydney, Australia; Tanya Smith, Harvard University; Asa Bradman and Brenda Eskenazi, UC Berkeley; Renaud Joannes-Boyau, Southern Cross University, Lismore, Australia; David Bishop, Dominic Hare and Philip Doble, University of Technology Sydney, Australia.

.


Related Links
University of California, Davis
All About Human Beings and How We Got To Be Here






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ABOUT US
Origins of human culture linked to rapid climate change
Cardiff UK (SPX) May 24, 2013
Rapid climate change during the Middle Stone Age, between 80,000 and 40,000 years ago, during the Middle Stone Age, sparked surges in cultural innovation in early modern human populations, according to new research. The research, published this month in Nature Communications, was conducted by a team of scientists from Cardiff University's School of Earth and Ocean Sciences, the Natural His ... read more


ABOUT US
Japan nuclear lab accident affected 30: agency

Kerry unveils $4 bn Palestinian investment plan

Death toll in China blast rises to 33: Xinhua

Italian town struggles to rebuild a year after quakes

ABOUT US
Ecuador's only satellite may have been damaged in space collision

New analysis yields improvements in 3D imaging

Professor who once had to work at Subway makes math breakthrough

Iron-platinum alloys could be new-generation hard drives

ABOUT US
Source of life running out: water scientists

S. Korea commission to probe $20 bln river project

Spain and France agree on fishing quota swap

LLNL scientist finds topography of Eastern Seaboard muddles ancient sea level changes

ABOUT US
Slovenian flyer completes eco-friendly Arctic voyage

Russia plans urgent evacuation of Arctic post as ice melts

Sea level influenced tropical climate during the last ice age

World's biggest ice sheets likely more stable than previously believed

ABOUT US
New research shows that potatoes provide one of the best nutritional values per penny

Researchers identify new target to boost plant resistance to insects and pathogens

The world's favorite fruit only better-tasting and longer-lasting

China to ban non-French 'champagne' copycats

ABOUT US
Massive Far East quake felt in Moscow, no casualties

Saudi researchers say drones could warn of desert flash floods

China steps up flood preparations after storms

Evacuation orders in Chile, Argentina over volcano

ABOUT US
Climate change drowning the 'Venice of Africa'

Outside View: Somalia's Jubaland

Nigeria says women, children held by Boko Haram freed

Africa celebrates progress and 50 years of 'unity'

ABOUT US
Monkey teeth help reveal Neanderthal weaning

China newborn rescued from toilet pipe: report

Origins of human culture linked to rapid climate change

Climate change boosted human development: study




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement