Featured Research

from universities, journals, and other organizations

Monkey teeth help reveal Neanderthal weaning

Date:
May 24, 2013
Source:
University of California - Davis
Summary:
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 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.

This molar tooth model with the cut face shows color-coded barium patterns merging with a microscopic map of growth lines.
Credit: 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?

Related Articles


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.

The work was funded by the U.S. Environmental Protection Agency, U.S. National Institute of Environmental Health Sciences, U.S. National Science Foundation, Australian National Health and Medical Research Council, Australian Research Council and Harvard University.


Story Source:

The above story is based on materials provided by University of California - Davis. Note: Materials may be edited for content and length.


Journal Reference:

  1. Christine Austin, Tanya M. Smith, Asa Bradman, Katie Hinde, Renaud Joannes-Boyau, David Bishop, Dominic J. Hare, Philip Doble, Brenda Eskenazi, Manish Arora. Barium distributions in teeth reveal early-life dietary transitions in primates. Nature, 2013; DOI: 10.1038/nature12169

Cite This Page:

University of California - Davis. "Monkey teeth help reveal Neanderthal weaning." ScienceDaily. ScienceDaily, 24 May 2013. <www.sciencedaily.com/releases/2013/05/130524104828.htm>.
University of California - Davis. (2013, May 24). Monkey teeth help reveal Neanderthal weaning. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2013/05/130524104828.htm
University of California - Davis. "Monkey teeth help reveal Neanderthal weaning." ScienceDaily. www.sciencedaily.com/releases/2013/05/130524104828.htm (accessed October 30, 2014).

Share This



More Fossils & Ruins News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Dracula's Dungeon May Have Been Found in Turkey

Dracula's Dungeon May Have Been Found in Turkey

AP (Oct. 29, 2014) — Historians think they may have discovered a dungeon in Turkey where the Romanian prince who inspired Count Dracula was once held captive. (Oct. 29) Video provided by AP
Powered by NewsLook.com
Study Doesn't Prove Megalodons Are Extinct, Never Needed To

Study Doesn't Prove Megalodons Are Extinct, Never Needed To

Newsy (Oct. 27, 2014) — How and why a study about when the giant prehistoric shark Megalodon went extinct got picked up as "proof" that it is. Video provided by Newsy
Powered by NewsLook.com
One-of-a-Kind BMW 507 Boat Found After 6 Decades

One-of-a-Kind BMW 507 Boat Found After 6 Decades

Buzz60 (Oct. 27, 2014) — BMW made just one BMW 507 boat, but it was lost for decades until a young man found and restored it. TC Newman (@PurpleTCNewman) shows the gorgeous boat! Video provided by Buzz60
Powered by NewsLook.com
Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) — Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
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:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

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