News / Science & Technology

Teeth May Hold Clues About Early Man's Weaning Patterns

FILE - The March 20, 2009 file photo shows reconstructions of Neanderthal men at the Neanderthal museum in Mettmann, Germany. Teeth of Neanderthal and early man may hold clues about Homo sapiens' evolutionary advantages over Neanderthal.
FILE - The March 20, 2009 file photo shows reconstructions of Neanderthal men at the Neanderthal museum in Mettmann, Germany. Teeth of Neanderthal and early man may hold clues about Homo sapiens' evolutionary advantages over Neanderthal.

Related Articles

Neanderthals Almost Extinct in Europe When Homo Sapiens Arrived

Finding suggest Neanderthals may have been more sensitive to dramatic changes in climate that occurred in last Ice Age than thought

Ancient Cave Art Could Be From Neanderthals

Markings in Spain are 40,000 years old

Neanderthal Genome Data Sheds Light on Human Ancestors

The DNA for the sequencing came from a toe bone found in a Siberian cave
VOA News
Scientists have long speculated that the early weaning of human babies gave homo sapiens an evolutionary advantage over Neanderthals. Now they may have discovered a way to prove the theory.

New research indicates that the level of barium measured in teeth corresponds with increased breastfeeding.

“People have speculated that an early weaning process in modern humans may have been part of their evolutionary advantage,” said Tanya Smith, an associate professor of human evolutionary biology at Harvard University in a statement. “We don’t have the data to answer that question yet, but we now have the method to be able to start collecting that data.”

According to the study, shorter nursing periods could have led to higher reproductive rates among modern humans.

By studying barium levels, “the timing of breastfeeding and the weaning process can be uncovered in tooth crowns – down to nearly the day,” according to the research, which was published in the journal Nature.

Teeth develop in a similar manner to trees, growing in regular layers made up of various minerals and small amounts of metals, like barium. By studying the barium levels in the layers of teeth, researchers were able to show that barium levels increase dramatically when breastfeeding begins and then fall off as infants begin eating a more varied diet.

Researchers first showed that barium levels correlate with breastfeeding using data from humans and monkeys whose infant diets were well documented.

“We can see when the barium shows up in the tooth after birth, and we see it increase over time, because an infant will take more milk as they get bigger and more active, and then you see it drop off in this beautiful, inverted U-shaped function,” said Katie Hinde, an assistant professor of human evolutionary biology at Harvard.

The methods for measuring barium levels could also be used on fossilized teeth.

“This is a game-changer in many ways, because this will allow us to go to museum collections and look at this as a proxy for how much milk different infants got from their mothers, and what their weaning process was like,” said Hinde. “We can now look at that within species, but we can also look at that among species.  That will tell us about the evolution of how mothers invest in their young.”

Smith adds that the research could lead to answers about other developmental differences between humans and Neanderthal.

“What does it mean that human and Neanderthal cranial development was different? What does it mean that their dental development was different? We haven’t been able to get at these questions in the fossil record, but now we can actually get at a real developmental benchmark. That’s why this is so exciting,” she said.

You May Like

Multimedia Obama, Modi Break Nuclear Deal Deadlock

Impasse over liability issues had been stalling bilateral civilian nuclear cooperation; deal reached at start of US president's three-day visit to India More

WHO's Late Efforts in Tackling Ebola Highlight Need for Reform

Health experts debate measures to reform agency’s response to global public health emergencies in special one-day session on deadly outbreak More

One Tumultuous Year in Power for CAR's President

As sectarian violence raged across Central African Republic, interim President Catherine Samba-Panza has Herculean task: to end civil war and put country back on right track More

This forum has been closed.
Comments
     
There are no comments in this forum. Be first and add one

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Worldwide Photo Workshops Empower Youthi
X
Julie Taboh
January 23, 2015 11:08 PM
Last September, 20 young adults from South Sudan took part in a National Geographic Photo Camp. They are among hundreds of students from around the world who have learned how to use a camera to tell the stories of the people in their communities through the powerful medium of photography. Three camp participants talked about their experiences recently on a visit to Washington. VOA’s Julie Taboh reports.
Video

Video Worldwide Photo Workshops Empower Youth

Last September, 20 young adults from South Sudan took part in a National Geographic Photo Camp. They are among hundreds of students from around the world who have learned how to use a camera to tell the stories of the people in their communities through the powerful medium of photography. Three camp participants talked about their experiences recently on a visit to Washington. VOA’s Julie Taboh reports.
Video

Video US, Japan Offer Lessons as Eurozone Launches Huge Stimulus

The Euro currency has fallen sharply after the European Central Bank announced a bigger-than-expected $67 billion-a-month quantitative easing program Thursday - commonly seen as a form of printing new money. Henry Ridgwell reports for VOA from London on whether the move might rescue the eurozone economy -- and what lessons have been learned from similar programs around the world.
Video

Video Nigerian Elections Pose Concern of Potential Conflict in 'Middle Belt'

Nigeria’s north-central state of Kaduna has long been the site of fighting between Muslims and Christians as well as between people of different ethnic groups. As the February elections approach, community and religious leaders are making plans they hope will keep the streets calm after results are announced. Chris Stein reports from the state capital, Kaduna.
Video

Video As Viewership Drops, Obama Puts His Message on YouTube

Ratings reports show President Obama’s State of the Union address this week drew the lowest number of viewers for this annual speech in 15 years. White House officials anticipated this, and the president has decided to take a non-traditional approach to getting his message out. VOA White House correspondent Luis Ramirez reports.
Video

Video S. Korean Businesses Want to End Trade Restrictions With North

Business leaders in South Korea are calling for President Park Geun-hye to ease trade restrictions with North Korea that were put in place in 2010 after the sinking of a South Korean warship.Pro-business groups argue that expanding trade and investment is not only good for business, it is also good for long-term regional peace and security. VOA’s Brian Padden reports.
Video

Video US Marching Bands Grow Into a Show of Their Own

The 2014 Super Bowl halftime show was the most-watched in history - attracting an estimated 115 million viewers. That event featured pop star Bruno Mars. But the halftime show tradition started with marching bands, which still dominate the entertainment at U.S. high school and college American football games. But as Enming Liu reports in this story narrated by Adrianna Zhang, marching bands have grown into a show of their own.
Video

Video Secular, Religious Kurds Face Off in Southeast Turkey

Turkey’s predominantly Kurdish southeast has been rocked by violence between religious and secular Kurds. Dorian Jones reports on the reasons behind the stand-off from the region's main city of Diyarbakir, which suffered the bloodiest fighting.
Video

Video Kenya: Misuse of Antibiotics Leading to Resistance by Immune System

In Kenya, the rise of drug resistant bacteria could reverse the gains made by medical science over diseases that were once treatable. Kenyans could be at risk of fatalities as a result if the power in antibiotics is not preserved. Lenny Ruvaga has more on the story from Nairobi.
Video

Video Solar-Powered Plane Getting Ready to Circumnavigate Globe

Pilots of the solar plane that already set records flying without a drop of fuel are close to making their first attempt to fly the craft around the globe. They plan to do it in 25 flying days over a five month period. VOA’s George Putic reports.
Video

Video How Experts Decide Ethiopia Has the Best Coffee

Ethiopia’s coffee has been ranked as the best in the world by an international group of coffee connoisseurs. Not surprisingly, coffee is a top export for the country. But at home it is a source of pride. Marthe van der Wolf in Addis Ababa decided to find out what makes the bean and brew so special and how experts make their determinations.
Video

Video Yazidi Refugees at Center of Political Fight Between Turkey, Kurds

The treatment of thousands of Yazidis refugees who fled to Turkey to escape attacks by Islamic State militants has become the center of a dispute between the Turkish government and the country's pro-Kurdish movement. VOA's Dorian Jones reports.
Video

Video World’s Richest 1% Forecast to Own More Than Half of Global Wealth

The combined wealth of the world's richest 1 percent will overtake that of the remaining 99 percent at some point in 2016, according to the anti-poverty charity Oxfam. Campaigners are demanding that policymakers take action to address the widening gap between the ‘haves’ and the ‘have nots’, as Henry Ridgwell reports for VOA from London.

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More

All About America

AppleAndroid