. Earth Science News .
ABOUT US
Ancient human relative Lucy's brain was surprisingly ape-like
by Brooks Hays
Washington DC (UPI) Apr 01, 2020

The early hominin Australopithecus afarensis -- known to many as Lucy -- walked upright and boasted a brain 20 percent bigger than a chimp's. Some scientists estimate Lucy used simple stone tools.

Lucy, which lived between 3.9 and 2.9 million years ago in Africa, is thought to be a close relative of the Homo genus, which includes modern humans. But new research suggests Australopithecus afarensis had a surprisingly ape-like brain.

Scientists were able to gain new insights into the development and organization of Lucy's brain by studying what are known as endocranial imprints. They published the results of their analysis Wednesday in the journal Science Advances.

"Brains do not fossilize, but as the brain grows and expands before and after birth, the tissues surrounding its outer layer leave an imprint in the bony braincase," Philipp Gunz, biological anthropologist at the Max Planck Institute for Evolutionary Anthropology in Germany, told UPI in an email. "Based on these endocasts we could measure endocranial volume, and infer key aspects of brain organization from impressions of brain convolutions in the skull."

Using CT scans, scientists were able to create detailed virtual models of endocranial imprints inside the braincases of several different Australopithecus afarensis specimens. By counting the dental growth lines -- like tree rings -- scientists were able to precisely date the age of the hominin specimens, including a young child.

"Using high resolution synchrotron scans, we could count the number of daily growth lines in the teeth, and found that the Dikika child died when it was 861 days old," Gunz said.

By comparing the endocasts of infants, adolescents and adults, scientists were able to better understand how the Lucy's brain developed.

When Gunz and his colleagues set out to study the development and organization of Lucy's brain, they were especially interested in locating the elusive endocranial imprint of a part of the brain called the lunate sulcus.

"A key difference between apes and humans involves the organization of the brain's parietal and occipital lobes," Gunz said. "In all ape brains, a well-defined lunate sulcus approximates the anterior boundary of the primary visual cortex of the occipital lobes."

Previously, researchers have hypothesized that Australopithecus afarensis evolved a more human-like brain with a backwards positioning of the lunate sulcus -- a repositioning that might have empowered sophisticated behaviors like tool usage, creative problem solving and vocal communication.

"Unfortunately, the lunate sulcus typically does not reproduce well on endocasts, so there is unresolved controversy about its position in australopiths," Gunz said. "The exceptionally well preserved endocast of the Dikika child has an unambiguous impression of a lunate sulcus in an ape-like position."

Scientists also discovered the signature of an ape-like lunate sulcus in the braincase of an adult australopith.

"Contrary to previous claims, we did not find evidence for brain reorganization in any Australopithecus afarensis endocast that preserves detailed sulcal impressions," Gunz said.

While the organization of Lucy's brain was quite ape-like, its growth during adolescent recalled the development of human brains.

"A comparison of infant and adult endocranial volumes nevertheless indicates more human-like protracted brain growth in Australopithecus afarensis, likely critical for the evolution of a long period of childhood learning in hominins," Gunz said.

Scientists plan to continue studying the endocranial imprints of geologically younger hominin fossils in order to better understand the evolution of brain structures among members of the genus Homo.


Related Links
All About Human Beings and How We Got To Be Here


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only


ABOUT US
2-million-year-old fossils suggest human ancestor was a tree climber
Washington DC (UPI) Mar 31, 2020
Analysis of ancient hominin remains recovered in South Africa suggests an early human ancestor regularly climbed trees. The earliest hominins walked upright on two legs, and scientists suspect they evolved from apes that had descended from the trees and begun traversing the land. But the latest research suggests hominins didn't abandon the trees altogether. Using a novel technique for analyzing the internal structure of ancient bones, scientists were able to locate evidence of tre ... read more

Comment using your Disqus, Facebook, Google or Twitter login.



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

ABOUT US
Coronavirus worst crisis since WWII, UN boss says as deaths surge

Aussie troops to help enforce mandatory quarantine

In virus fight, Singapore may jail people who stand close

North Macedonia joins NATO, adopts alliance's COVID-19 response tool

ABOUT US
DLR retrofits 3D printer to produce medical protective equipment

Print sprint: Bosnians 3D print face-shields to combat coroanvirus

Zoom under scrutiny in US over privacy, porn hacks

World Centric announces new World Centric leaf fiber lids

ABOUT US
Study reveals where marine species are moving as oceans warm

Water crisis could sabotage Zimbabwe's coronavirus lockdown

Unique structural fluctuations at ice surface promote autoionization of water molecules

Lockheed Martin receives $12.3 million to develop underwater drone

ABOUT US
Hidden source of carbon found at the Arctic coast

How horses can save the permafrost

Increasingly mobile sea ice risks polluting Arctic neighbors

GRACE, GRACE-FO satellite data track ice loss at the poles

ABOUT US
Wuhan's virus ground-zero market hides in plain sight

Instacart gig workers threaten walkoff over virus safety

Could Satellites Help Head Off a Locust Invasion?

Kenya bans controversial donkey slaughter trade

ABOUT US
6.5 magnitude quake hits US state of Idaho

Indonesian volcano spews massive ash cloud

Quake hits off Russia's Kuril Islands, prompts tsunami alert

Powerful quake damages buildings in Croatia capital

ABOUT US
Nigerians brace for lockdown as Africa tries to halt virus

Dozens of S.Africans exit quarantine after China return

Chad declares Lake areas 'war zone' after deadly Boko Haram attack

S.African policeman arrested for murder amid virus lockdown

ABOUT US
Neanderthals were eating mussels, fish, seals 80K years ago

Scientists unveil smaller, more powerful brain-machine interface

2-million-year-old fossils suggest human ancestor was a tree climber

Nextdoor, the network for neighbors, grows in age of social distancing









The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news 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. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. 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. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.