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

Egypt's Suez Canal Dreams Tempered by Continued Unrest

Seen as a potential driver of recovery, Cairo’s plan to expand waterway had been raising hopes to give country much needed economic boost More

Ebola Maternity Ward in Sierra Leone First of its Kind

Country already had one of world's highest maternal mortality rates before Ebola arrived, virus has added even more complications to health care More

Malaysia Flight 370 Disappearance Ruled Accident

Aircraft disappeared on March 8, 2014; with ruling, families of 239 passengers and crew can now seek compensation from airline 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.
Groundbreaking Hand-Painted Documentary About Van Gogh in Productioni
X
George Putic
January 29, 2015 9:43 PM
The troubled life of the famous 19th century Dutch painter Vincent van Gogh has been told through many books and films, but never in the way a group of filmmakers now intends to do. "Loving Vincent " will be the first ever feature-length film made of animated hand-painted images, done in the style of the late artist. VOA’s George Putic reports.
Video

Video Groundbreaking Hand-Painted Documentary About Van Gogh in Production

The troubled life of the famous 19th century Dutch painter Vincent van Gogh has been told through many books and films, but never in the way a group of filmmakers now intends to do. "Loving Vincent " will be the first ever feature-length film made of animated hand-painted images, done in the style of the late artist. VOA’s George Putic reports.
Video

Video Rock-Consuming Organisms Alter Views of Life Processes

Scientists thought they knew much about how life works, until a discovery more than two decades ago challenged conventional beliefs. Scientists found that there are organisms that breathe rocks. And it is only recently that the scientific community is accepting that there are organisms that could get energy out of rocks. Correspondent Elizabeth Lee reports.
Video

Video Paris Attacks Highlight Global Weapons Black Market

As law enforcement officials piece together how the Paris and Belgian terror cells carried out their recent attacks, questions are being asked about how they obtained military grade assault weapons - which are illegal in the European Union. As VOA's Jeff Swicord reports, experts say there is a very active worldwide black market for these weapons, and criminals and terrorists are buying.
Video

Video Activists Accuse China of Targeting Religious Freedom

The U.S.-based Chinese religious rights group ChinaAid says 2014 was the worst year for religious freedom in China since the end of the Cultural Revolution. As Ye Fan reports, activists say Beijing has been tightening religious controls ever since Chinese leader Xi Jinping came to office. Hu Wei narrates.
Video

Video Super Bowl Ads Compete for Eyes on TV, Web

Super Bowl Sunday (Feb. 1) is about more than just the NFL's American football championship and big parties to watch the game. Viewers also tune in for the world famous commercials that send Facebook and Twitter abuzz. Daniela Schrier reports on the social media rewards for America’s priciest advertising.
Video

Video Theologians Cast Doubt on Morality of Drone Strikes

In 2006, stirred by photos of U.S. soldiers mistreating Iraqi prisoners, a group of American faith leaders and academics launched the National Religious Campaign Against Torture. It played an important role in getting Congress to investigate, and the president to ban, torture. VOA's Jerome Socolovsky reports.
Video

Video Freedom on Decline Worldwide, Report Says

The state of global freedom declined for the ninth consecutive year in 2014, according to global watchdog Freedom House's annual report released Wednesday. VOA's William Gallo has more.
Video

Video MRI Seems to Help Diagnose Prostate Cancer, Preliminary Study Shows

Just as with mammography used to detect breast cancer, there's a lot of controversy about tests used to diagnose prostate cancer. Fortunately, a new study shows doctors may now have a more reliable way to diagnose prostate cancer for high risk patients. More from VOA's Carol Pearson.
Video

Video Smartphones About to Make Leap, Carry Basic Senses

Long-distance communication contains mostly sounds and pictures - for now. But scientists in Britain say they are close to creating additions for our smartphones that will make it possible to send taste, smell and even a basic touch. VOA’s George Putic reports.
Video

Video Former Sudan 'Lost Boy' Becomes Chess Master in NYC

In the mid-1980’s, thousands of Sudanese boys escaped the country's civil war by walking for weeks, then months and finally for more than a year, up to 1,500 kilometers across three countries. The so-called Lost Boys of the Sudan had little time for games. But one of them later mastered the game of chess, and now teaches it to children in the New York area. VOA’s Bernard Shusman in New York has his story.
Video

Video NASA Monitors Earth’s Vital Signs From Space

The U.S. space agency, NASA, is wrapping up its busiest 12-month period in more than a decade, with three missions launched in 2014 and two this month, one in early January and the fifth scheduled for January 29. As VOA’s Rosanne Skirble reports, the instruments being lifted into orbit are focused on Earth’s vital life support systems and how they are responding to a warmer planet.
Video

Video Crowded Republican Presidential Field Off to Early Start for 2016

It seems early, but the 2016 U.S. presidential election campaign is already heating up. Though no one has officially announced a candidacy, several potential Republican contenders have been busy speaking to conservative groups about making a White House run next year. Many of the possible contenders are critical of the Obama administration’s foreign policy record. VOA national correspondent Jim Malone reports.

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