An enormous pile of enormous bones excavated in Ecuador has given new insight into the behaviour of extinct giant ground sloths.
Giant ground sloths lived in North and South America for millions of years until their extinction around the end of the last ice age — about 11,000 years ago. The largest species of giant ground sloths rivalled African elephants in size, and this new research suggests that their behaviour might have been very elephant-like as well.
“Between 10,000 and 50,000 years ago, depending on which continent you’re on, basically all ice-free continents had ecosystems that looked a lot more like a modern African ecosystem,” said researcher Emily Lindsey in an interview with Bob McDonald on Quirks & Quarks.
“There were a lot of very large animals in that ecosystem and these sloths … were some of the largest.”
Seeping tar was the key to fossil preservation
Giant ground sloth remains have been found in many locations in the Americas, but the find at a site called Tanque Loma in Ecuador in the early 2000s was unique. First uncovered by an oil company during exploration, the site was a “tar seep” in which plant and animal remains had been sealed in naturally occurring tar.
The most famous similar site is Lindsey’s research home — she’s assistant curator and excavation site director at the La Brea Tar Pits in Los Angeles. But she said the preservation here is a little different.
Researcher Emily Lindsey at the excavation site in Ecuador surrounded by sloth bones. (Emily Lindsey)
“It’s a site that probably formed not through large animals getting actually trapped in the tar, but from an asphalt seep that arose after a bone bed was deposited, and just fortuitously preserved the bone bed in situ.”
Excavations over a period of nearly two decades revealed that the tar seep had preserved various plant and animal remains. The most notable were hundreds of bones from one of the largest species of giant sloth that ever lived, known scientifically as Eremotherium laurillardi, which survived as a species for about five million years.
Adults of this species weighed upward of three tonnes and could reach a length of up to six metres. They were ground dwelling herbivores who could feed on foliage high in tree tops by rearing up on their powerful hind legs.
Possibly a family group
The excavated bones turned out to be from at least 22 individual animals, from small, dog-sized infants to full-sized adults. The context in which the bones were found suggested the animals died at roughly the same time, and also revealed the nature of the location.
“We believe that the site was a spring-fed marsh,” said Lindsey. “[It] probably had a lot of vegetation and it was probably an attractive area for large animals to come and spend time in [an] otherwise still somewhat arid tropical environment.”
La Brea Tar Pits staff and Ecuadoran students excavate and collect giant sloth bones at the Tanque Loma tar pit locality in Ecuador. (Emily Lindsey)
This seemed like a benign environment for giant sloths, so finding the remains of so many animals that had died at the same time was a mystery.
Fortunately the tar seep had preserved more evidence than bones. In and around the remains was a large amount of plant material — small branches, stems and twigs, all sharply cut into roughly 2.5-centimetre lengths.
At first Lindsey didn’t know what to make of this material.
“It wasn’t until later when I was talking with a friend who is a retired professor of geography, and he told me a story that he had been monitoring a hippo wallow in Africa back in the ’70s,” she said.
Her colleague described how a drought had concentrated hippos around the small pond, and as a matter of course, the hippos defecated into it. A large amount of feces concentrated in the water.
“It created this very unsanitary environment and thus this contributed to this rapid development of this disease that ended up wiping out their population,” she said.
Lindsey then realized that the characteristically shaped plant material she’d found associated with the sloth bones had probably been cut by their teeth, and was either gut contents or feces — a large amount of it.
Hippos congregate in large numbers in pools in Africa, contaminating them with feces. Observations of a die-off at such a pool inspired the idea that a group of ancient ground sloths might have died in a similar way. (Chris Dutton)
Contaminated water might have led to catastrophe
“At least a plausible explanation for how these animals died was something similar to what happened with this hippopotamus population that my co-author had observed in Africa,” Lindsey said.
Animals trapped by drought conditions near the shrinking wallow contaminated it, and this led to the mass death.
That meant they had a likely explanation for how the animals died. But more interesting was what the remains and the site said about how giant sloths lived.
“It’s not implausible to think, based on group situations that we see in other very large animals today, like elephants or other large savanna vertebrates, that there’s some sort of familial connection,” said Lindsey.
“These animals all died at a very similar time and were probably part of one large group. So they probably were social or gregarious animals.”
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
