These human ancestors weren’t as lonely as experts thought
36 fossil fragments from vertebrate animals were documented by researchers. Credit: Quaternary Environments and Humans
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For years, archeologists assumed the ancient Homo erectus population that lived on present-day Java existed in general isolation from nearby island relatives. However, a pair of fossilized skull fragments recently found off the Javanese coast are helping experts recontextualize the lives of the region’s H. erectus populations as they existed around 140,000 years ago. According to a study published May 15 in the journal Quaternary Environments and Humans, life for the Javanese H. erectus wasn’t always as lonely as we thought.
Today, Indonesia consists of multiple islands between Asia and Australia, but that hasn’t always been the case. Beginning roughly 2.6 million years ago, the larger area has occasionally existed during periods of lower ocean levels as a larger, unified lowland landmass known as Sundaland. While H. erectus fossils have previously been found on Java itself, none were known to exist further outward in areas like the Madura Strait, which separates the islands of Madura from Central Java.
A: The Sunda Shelf of Southeast Asia, with the Indonesian archipelago. Box indicates the position of map B. B: Eastern Java, the Madura Strait, the Solo River, Surabaya and other sites mentioned in the text. Box indicates position of map C. C: The Madura Strait north of Surabaya, with the sand extraction area and the BMS land reclamation. Map data: GEBCO and ALOS / Credit: Quaternary Environments and Humans
That all changed thanks to over 176.5 million cubic feet of sand. The massive amount of sediment was dredged over 2014 to 2015 as part of an Indonesia land reclamation project, but it soon became clear that the sand also contained valuable historical remains. Scouring the material ultimately yielded around 6,000 fossil specimens from ancient fish, reptiles, and mammals–including the unexpected pair of H. erectus skull fragments.
According to Harold Berghuis, study co-author and an archeologist at Leiden University in the Netherlands, their team’s discoveries are “truly unique.”
“The fossils come from a drowned river valley, which filled up over time with river sandapproximately 140,000 years ago,” he said in an accompanying statement.
Berghuis described that era as the “penultimate glacial period.” Earth’s Northern Hemisphere was so populated with glaciers, that the global sea level averaged nearly 1,100 feet lower than it does today. Because of this, Sundaland in the time of H. erectus greatly resembled the African savannah of today—largely dry grassland broken up by major rivers surrounded by narrow strips of forests.
“Here they had water, shellfish, fish, edible plants, seeds and fruit all year round,” said Berghuis.
Sundaland also featured a variety of animals, including multiple species of elephants, rhinos, and crocodiles. Strikingly, the bones the team found even have evidence of butchery by H. erectus.
“Among our new finds are cut marks on the bones of water turtles and large numbers of broken bovid bones, which point to hunting and consumption of bone marrow,” Berghuis added.
While this contrasts with earlier Javanese H. erectus populations, it had previously been documented in more modern human species who lived on the Asian mainland. According to the study’s authors, this indicates that Sundaland’s H. erectus may have learned those techniques from them.
“This suggests there may have been contact between these hominin groups, or even genetic exchange,” theorized Berghuis.
#these #human #ancestors #werent #lonely
These human ancestors weren’t as lonely as experts thought
36 fossil fragments from vertebrate animals were documented by researchers. Credit: Quaternary Environments and Humans
Get the Popular Science daily newsletter💡
Breakthroughs, discoveries, and DIY tips sent every weekday.
For years, archeologists assumed the ancient Homo erectus population that lived on present-day Java existed in general isolation from nearby island relatives. However, a pair of fossilized skull fragments recently found off the Javanese coast are helping experts recontextualize the lives of the region’s H. erectus populations as they existed around 140,000 years ago. According to a study published May 15 in the journal Quaternary Environments and Humans, life for the Javanese H. erectus wasn’t always as lonely as we thought.
Today, Indonesia consists of multiple islands between Asia and Australia, but that hasn’t always been the case. Beginning roughly 2.6 million years ago, the larger area has occasionally existed during periods of lower ocean levels as a larger, unified lowland landmass known as Sundaland. While H. erectus fossils have previously been found on Java itself, none were known to exist further outward in areas like the Madura Strait, which separates the islands of Madura from Central Java.
A: The Sunda Shelf of Southeast Asia, with the Indonesian archipelago. Box indicates the position of map B. B: Eastern Java, the Madura Strait, the Solo River, Surabaya and other sites mentioned in the text. Box indicates position of map C. C: The Madura Strait north of Surabaya, with the sand extraction area and the BMS land reclamation. Map data: GEBCO and ALOS / Credit: Quaternary Environments and Humans
That all changed thanks to over 176.5 million cubic feet of sand. The massive amount of sediment was dredged over 2014 to 2015 as part of an Indonesia land reclamation project, but it soon became clear that the sand also contained valuable historical remains. Scouring the material ultimately yielded around 6,000 fossil specimens from ancient fish, reptiles, and mammals–including the unexpected pair of H. erectus skull fragments.
According to Harold Berghuis, study co-author and an archeologist at Leiden University in the Netherlands, their team’s discoveries are “truly unique.”
“The fossils come from a drowned river valley, which filled up over time with river sandapproximately 140,000 years ago,” he said in an accompanying statement.
Berghuis described that era as the “penultimate glacial period.” Earth’s Northern Hemisphere was so populated with glaciers, that the global sea level averaged nearly 1,100 feet lower than it does today. Because of this, Sundaland in the time of H. erectus greatly resembled the African savannah of today—largely dry grassland broken up by major rivers surrounded by narrow strips of forests.
“Here they had water, shellfish, fish, edible plants, seeds and fruit all year round,” said Berghuis.
Sundaland also featured a variety of animals, including multiple species of elephants, rhinos, and crocodiles. Strikingly, the bones the team found even have evidence of butchery by H. erectus.
“Among our new finds are cut marks on the bones of water turtles and large numbers of broken bovid bones, which point to hunting and consumption of bone marrow,” Berghuis added.
While this contrasts with earlier Javanese H. erectus populations, it had previously been documented in more modern human species who lived on the Asian mainland. According to the study’s authors, this indicates that Sundaland’s H. erectus may have learned those techniques from them.
“This suggests there may have been contact between these hominin groups, or even genetic exchange,” theorized Berghuis.
#these #human #ancestors #werent #lonely