The bone of an ancient human relative shows signs of cutting with stone tools – of another human relative looking to cut meat to eat.
The nine cut marks on a 1.45-million-year-old left shin bone from a relative of A wise man was found in northern Kenya.
Analysis of 3D models of the fossil’s surface revealed that the cut marks were dead ringers for damage caused by stone tools.
National Museum of Natural History paleoanthropologist Briana Pobiner said, “The information we have tells us that hominins were probably eating other hominins at least 1.45 million years ago.
“There are many other examples of species from the human evolutionary tree that consumed each other for nutrition, but this fossil indicates that relatives of our species ate each other. one to live more in the past than we know.”
Read more: Melting snow in the Himalayas drives the growth of green sea slime visible from space
Pobiner first came across the fossilized tibia, or shin bone, in the collections of the National Museums of Kenya’s Nairobi National Museum while searching for clues as to which prehistoric predators may have hunted and eaten early human relatives.
Using a handheld magnifying lens, Pobiner was peering at the tibia looking for bite marks from dead animals when instead he noticed what immediately looked to him like evidence of murder.
Pobiner sent molds of the incisions—made using the same material dentists use to create impressions of teeth—to co-author Michael Pante of Colorado State University.
Pante created 3D scans of the molds and compared the shape of the marks to a database of 898 individual tooth, butchery and trample marks created through controlled experiments.
Read more: A 1988 warning about climate change was almost right
Analysis positively identified nine of the 11 marks as clear matches for the type of damage caused by stone tools. The other two marks are likely bite marks from a big cat, with a lion being the closest match.
According to Pobiner, the bite marks may have come from one of three different types of saber-tooth cats that roamed the landscape at the time the owner of this shin bone was alive.
By themselves, the cut marks don’t prove that the human relative who caused them also made food from the leg, but Pobiner said it’s the most likely scenario.
He explained that the cuts are located where a calf muscle attaches to the bone—a good place to cut if the goal is to remove a chunk of flesh. The cut marks are also all oriented in the same way, such that a hand holding a stone tool can make them all in a row without changing the grip or adjusting the angle of the cut attack
“These cut marks are very similar to what I’ve seen on animal fossils processed for consumption,” Pobiner said. “It seems likely that the meat from this leg was eaten and that it was eaten for nutrition as opposed to a ritual.”
Although this case may appear to be cannibalism to a casual observer, Pobiner said there is not enough evidence to make that determination because cannibalism requires that the eater and the eaten come from the same species.
The fossil shin bone was first identified as Australopithecus boisei and then in 1990 as Homo erectus, but now, experts agree there is not enough information to assign the specimen to a specific hominin species.
The use of stone tools also does not narrow down which species may have been doing the cutting.
Recent research from Rick Potts, the National Museum of Natural History’s Peter Buck Chair of Human Origins, further questions the once-common assumption that only one genus, Homo, made and used stone tools.
So, this fossil could be a trace of prehistoric cannibalism, but it’s also possible that it’s a case of a species eating its evolutionary cousin.
None of the chip marks overlap the two bite marks, making it difficult to infer anything about the sequence of events that occurred.
For example, a big cat may have scavenged the remains after hominins removed most of the meat from the leg bone. It’s also possible that a big cat killed an unlucky hominin and then drove off or drove off before opportunistic hominins took over the kill.
Another fossil—a skull first found in South Africa in 1976—has previously sparked debate about the earliest known case of human relatives butchering each other. Estimates for the age of this skull range from 1.5 to 2.6 million years old.
To resolve the issue of whether the fossil tibia he and his colleagues studied is the oldest cut-marked hominin fossil, Pobiner said he wants to re-examine the skull from South Africa, which is said to have cut marks using both methods observed in the present study.
He also said that this new surprising find is proof of the value of the museum’s collections.
“You can make some amazing discoveries by going back into museum collections and looking at fossils again,” Pobiner said. “Not everyone sees everything the first time. It takes a community of scientists coming with different questions and approaches to continue to expand our knowledge of the world.”
Watch: Most of us have herpes thanks to ancient interspecies sex
#Ancient #human #ancestors #bones #butchered #ancestor #meat