Females from two hominid species that roamed the South African savanna more than 1 million years ago left their families and struck out on their own, while their male counterparts tended the home fires, an international team of researchers said on Wednesday.
The findings, published in the journal Nature, came from an analysis of traces of the isotope strontium that had built up in adult teeth from two extinct groups —Australopithecus africanus and Paranthropus robustus.
Both Paranthropus robustus and Australopithecus africanus were part of a line of close human relatives known as australopithecines that included the Ethiopian fossil Lucy, estimated to be 3.2 million years old and regarded by many as the matriarch of modern humans.
Photo: AFP/ University of Colorado at Boulder/Darryl de Ruiter
To understand how these hominids used the landscape and formed social groups, the team, led by Sandi Copeland of Colorado University Boulder, turned to the ancient dental record.
Using a high-tech analysis known as laser ablation, Copeland’s team zapped the hominid teeth with lasers to measure ratios of strontium, a naturally occurring element found in rocks and soils that is absorbed by plants and animals.
The team tested 19 teeth dating from roughly 2.7 to 1.7 million years ago from both Australopithecus africanus and Paranthropus robustus individuals from the the Sterkfontein and Swartkrans cave systems in South Africa.
The team found more than half of the smaller, female teeth came from outside the local area, but only about 10 percent of the male hominid teeth were from elsewhere.
That suggests that males likely grew up and died in the same area, Copeland said.
She said the pattern in which the females left home in search of a mate is similar to chimpanzees and some groups of modern humans, in which a woman leaves her family to join her husband’s household.
However, it is different from most other primates — including gorillas — where the females stay with the group they are born into and the males move elsewhere.
“In any mammal group, including primates, where individuals live in groups, either the females or males must eventually leave their birth community. One of the important reasons for this is to prevent inbreeding,” Copeland said. “In most mammals, it is usually the males that leave their home community.”
She said the findings were a bit of a surprise.
“We assumed more of the hominids would be from non-local areas since it is generally thought the evolution of bipedalism was due in part to allow individuals to range longer distances,” Copeland said.
Such small home ranges suggest that bipedalism evolved for other reasons, she said.
Republican US lawmakers on Friday criticized US President Joe Biden’s administration after sanctioned Chinese telecoms equipment giant Huawei unveiled a laptop this week powered by an Intel artificial intelligence (AI) chip. The US placed Huawei on a trade restriction list in 2019 for contravening Iran sanctions, part of a broader effort to hobble Beijing’s technological advances. Placement on the list means the company’s suppliers have to seek a special, difficult-to-obtain license before shipping to it. One such license, issued by then-US president Donald Trump’s administration, has allowed Intel to ship central processors to Huawei for use in laptops since 2020. China hardliners
A top Vietnamese property tycoon was on Thursday sentenced to death in one of the biggest corruption cases in history, with an estimated US$27 billion in damages. A panel of three hand-picked jurors and two judges rejected all defense arguments by Truong My Lan, chair of major developer Van Thinh Phat, who was found guilty of swindling cash from Saigon Commercial Bank (SCB) over a decade. “The defendant’s actions ... eroded people’s trust in the leadership of the [Communist] Party and state,” read the verdict at the trial in Ho Chi Minh City. After the five-week trial, 85 others were also sentenced on
Conjoined twins Lori and George Schappell, who pursued separate careers, interests and relationships during lives that defied medical expectations, died this month in Pennsylvania, funeral home officials said. They were 62. The twins, listed by Guinness World Records as the oldest living conjoined twins, died on April 7 at the Hospital of the University of Pennsylvania, obituaries posted by Leibensperger Funeral Homes of Hamburg said. The cause of death was not detailed. “When we were born, the doctors didn’t think we’d make 30, but we proved them wrong,” Lori said in an interview when they turned 50, the Philadelphia Inquirer reported. The
RAMPAGE: A Palestinian man was left dead after dozens of Israeli settlers searching for a missing 14-year-old boy stormed a village in the Israeli-occupied West Bank US President Joe Biden on Friday said he expected Iran to attack Israel “sooner, rather than later” and warned Tehran not to proceed. Asked by reporters about his message to Iran, Biden simply said: “Don’t,” underscoring Washington’s commitment to defend Israel. “We are devoted to the defense of Israel. We will support Israel. We will help defend Israel and Iran will not succeed,” he said. Biden said he would not divulge secure information, but said his expectation was that an attack could come “sooner, rather than later.” Israel braced on Friday for an attack by Iran or its proxies as warnings grew of