Featured Research

from universities, journals, and other organizations

Early Hominids May Have Behaved More 'Human' Than We Had Thought

Date:
August 7, 2003
Source:
Ohio State University
Summary:
Our earliest ancestors probably behaved in a much more "human" way than most scientists have previously thought, according to a recent study that looked at early hominid fossils from Ethiopia.

COLUMBUS, Ohio – Our earliest ancestors probably behaved in a much more "human" way than most scientists have previously thought, according to a recent study that looked at early hominid fossils from Ethiopia.

Previously skeptical, an Ohio State University anthropologist now supports the idea that the minimal size differences between male and female pre-hominids suggest that they lived in a more cooperative and less competitive society.

The evidence centers on the extent of sexual dimorphism – differences in size based on sex -- that existed among these early primates and what it suggests about the social structure of these creatures.

In a paper published in the August 5 issue of the Proceedings of the National Academy of Sciences, researchers at Kent State University reported that remains of both male and female specimens of Australopithecus afarensis showed fewer differences based on size than most paleontologists had earlier expected.

After comparing these bones with the near-complete skeletons of the fossil "Lucy," the researchers argue that the social structure of our earliest ancestors compared more to that of modern humans and chimpanzees than it does to gorillas and orangutans, as had previously been thought.

Gorillas, orangutans and baboons are known to have social structures built around fierce competition among males. Chimps and humans however, while still competitive, are more cooperative, giving them a greater degree of "humanness."

In a commentary in the journal, Clark Spencer Larsen, distinguished professor and chair of anthropology at Ohio State, argued that the Kent State study was the best to date at linking sexual dimorphism in early hominids to their probable social structure.

"These researchers have been able to show convincingly that, from the fossil remains, there was very little sexual dimorphism in these early hominids," Larsen said. "From that, I think we can extrapolate some behaviors – specifically that males were cooperating more than they were competing among themselves – a distinctly 'human' behavior."

Larsen believes that this male cooperation is the product of evolutionary change. "The success of this cooperation proved valuable to these early ancestors and has become a trait among humans," he said.

Paleontologists knew that there were minimal size differences between males and females since Homo sapiens evolved but the fossil record is so sparse, they were unsure of whether pre-Homo species showed more of less sexual dimorphism. Modern humans show no more than 15 percent size difference on average, Larsen said.

This new study, however, took advantage of a novel fossil find at Site 333 in the Afar Triangle of Ethiopia where remains of 13 individuals were discovered in 1975. Scientists believe that they all died at the same time, giving a possible "snapshot" view of how they lived.

Using the "Lucy" skeleton from a nearby site as a template, the Kent State researchers were able to use femur "head" size as a key to extrapolate the size of the individuals from Site 333.

"Only in the last few years have we realized that an individual's femur head size is a good proxy for its body weight," Larsen said.

The comparison showed that the sex-based size differences among the fossils at Site 333 were no greater than those for modern humans, suggesting that the same kind of modern social structure with cooperating males also occurred in the days of Australopithecus afarensis.

"I think what we are seeing here are the very first glimpses of 'humanness' in these early hominids dating back 3 million to 4 million years," he said.


Story Source:

The above story is based on materials provided by Ohio State University. Note: Materials may be edited for content and length.


Cite This Page:

Ohio State University. "Early Hominids May Have Behaved More 'Human' Than We Had Thought." ScienceDaily. ScienceDaily, 7 August 2003. <www.sciencedaily.com/releases/2003/08/030807075457.htm>.
Ohio State University. (2003, August 7). Early Hominids May Have Behaved More 'Human' Than We Had Thought. ScienceDaily. Retrieved August 23, 2014 from www.sciencedaily.com/releases/2003/08/030807075457.htm
Ohio State University. "Early Hominids May Have Behaved More 'Human' Than We Had Thought." ScienceDaily. www.sciencedaily.com/releases/2003/08/030807075457.htm (accessed August 23, 2014).

Share This




More Fossils & Ruins News

Saturday, August 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Neanderthals Probably Died Out Earlier Than We Thought

Neanderthals Probably Died Out Earlier Than We Thought

Newsy (Aug. 21, 2014) — A new study is packed with interesting Neanderthal-related findings, including a "definitive answer" to when they went extinct. Video provided by Newsy
Powered by NewsLook.com
Disquieting Times for Malaysia's 'fish Listeners'

Disquieting Times for Malaysia's 'fish Listeners'

AFP (Aug. 19, 2014) — Malaysia's last "fish listeners" -- practitioners of a dying local art of listening underwater to locate their quarry -- try to keep the ancient technique alive in the face of industrial trawling and the depletion of stocks. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
Mother And Son Find Woolly Mammoth Tusks 22 Years Apart

Mother And Son Find Woolly Mammoth Tusks 22 Years Apart

Newsy (Aug. 15, 2014) — A mother and son in Alaska uncovered woolly mammoth tusks in the same river more than two decades apart. Video provided by Newsy
Powered by NewsLook.com
Fossils Reveal Ancient Flying Reptile With 'Butterfly Head'

Fossils Reveal Ancient Flying Reptile With 'Butterfly Head'

Newsy (Aug. 14, 2014) — Newly found fossils reveal a previously unknown species of flying reptile with a really weird head, which some say looks like a butterfly. 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