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Fish finger fossils show the beginnings of hands

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About 374 million years ago, life on Earth began to transition out of the world’s oceans to walk on land. This gave rise to the tetrapods, or four-limbed vertebrates, that included dinosaurs, land animals and eventually humans. Scientists consider this transition from water to land, and animals acquiring hands and feet, to be one of the most significant events in the history of life on Earth.
But the fossil record about the evolutionary step between marine and land life is sparse. Researchers have focused their efforts on tetrapod-like fish, called elpistostegalians, that lived between 359 and 393 million years ago during the Middle and Late Devonian periods.
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Until now, they had never found the complete skeleton of the pectoral fin, also known as the fore-fin. But researchers have discovered one of the most complete elpistostegalian fossils yet: a 5-foot-long fossilized fish in Miguasha, Quebec.
CT scans of the skeleton revealed at least two skeletal digits that resembled fingers, as well as three more potential ones. They also found an arm, elbow, forearm and wrist attached to the finger-like digits.
All of them were still contained within a fin ray, or webbed flipper-like appendage, but the researchers believe it’s the missing link between fish fins and vertebrate hands.
This is an artist's reconstruction of the fish and its fin, which contained finger-like digits.This is an artist's reconstruction of the fish and its fin, which contained finger-like digits.
The study published Wednesday in the journal Nature.
“Today we announce in the journal Nature our discovery of a complete specimen of a tetrapod-like fish, called Elpistostege, which reveals extraordinary new information about the evolution of the vertebrate hand,” said John Long, study author and Strategic Professor in Palaeontology at Flinders University in Australia.
“This is the first time that we have unequivocally discovered fingers locked in a fin with fin-rays in any known fish. The articulating digits in the fin are like the finger bones found in the hands of most animals.”
The researchers analyzed the fin to determine its skeletal structure.The researchers analyzed the fin to determine its skeletal structure.
To date, this skeletal arrangement is the most similar to previously found tetrapods. And the fact that it was located in the fore-fin suggests it was more like a hand.
This appendage would have aided fish as they explored shallow water habits during the Late Devonian period.
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“The origin of digits relates to developing the capability for the fish to support its weight in shallow water or for short trips out on land,” said Richard Cloutier, study co-author and professor at the Universite du Quebec a Rimouski. “The increased number of small bones in the fin allows more planes of flexibility to spread out its weight through the fin.”
“The other features the study revealed concerning the structure of the upper arm bone or humerus, which also shows features present that are shared with early amphibians,” Cloutier said. “Elpistostege is not necessarily our ancestor, but it is [the] closest we can get to a true ‘transitional fossil’, an intermediate between fishes and tetrapods.”
A comparison of the fish skeleton and a human skeleton show the similarities.A comparison of the fish skeleton and a human skeleton show the similarities.
Previously, researchers have studied these tetrapod-like fish to better understand how creatures adapted to breathing, hearing and eating on land as they emerged from the water.
Elpistostege watsoni, as the fish has been dubbed, would have been the largest predator dominating Quebec’s shallow marine and estuary habitat 380 million years ago. Sharp fangs helped it snack on other large fish, whose fossils were found in the same area.
Fragments of fossils belonging to this fish were initially found in Quebec in 1938. At the time, they only found a portion of the skull’s roof and assumed it was a tetrapod.
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Another piece of the puzzle was found in 1985, revealing it was a lobe-finned fish. Lobe-finned fish differ from others because their fleshy fins connect to the body through a single bone.
This tree shows the different branches of evolution as creatures transitioned from sea to land.This tree shows the different branches of evolution as creatures transitioned from sea to land.
And the most complete fossil, which was part of the this study, was originally found in 2010. CT scans of the fossil, followed by detailed analysis of its backbone and fin, occurred after the discovery. The researchers partnered with colleagues from other institutions to continue CT scans, which revealed the digits found in the fin. Their work was finally completed in 2019.
Their years of analysis revealed that this was the most evolutionary fish of its kind.
“This finding pushes back the origin of digits in vertebrates to the fish level, and tells us that the patterning for the vertebrate hand was first developed deep in evolution, just before fishes left the water,” Long said.

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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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.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

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.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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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.”

The Canadian Press. All rights reserved.

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B.C. sets up a panel on bear deaths, will review conservation officer training

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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.

The Canadian Press. All rights reserved.

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