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This Ancient Fish Represents The Earliest Known Evolutionary Evidence of Fingers

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The four-limbed animals of the world have several things in common. Spines. Bilateral symmetry. And most of us have (or, in the case of birds, had) five digits at the end of each of our four limbs.

When and how these digits emerged in animals has been something of a mystery. Palaeontologists have just found the earliest evidence of this anatomical feature, in the fin of a fish that lived 380 million years ago.

The rudimentary digit bones may not look like much, but they mark one of the most important transitions in vertebrate evolution.

“We have made a major breakthrough in the origin of how the hand was first formed for all vertebrates,” palaeontologist John Long of Flinders University in Australia told ScienceAlert.

“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,” he said in a statement.

The transition from aquatic fish to four-limbed creature (tetrapod) is one of the most important in evolutionary history, yet there are significant gaps in our knowledge. One of those gaps has been the point at which fish emerged from the depths and started foraging in shallower waters – what’s considered to be an intermediate step before crawling out onto land.

In order to complete that transition, animals would have needed something pretty vital for crawling – that is, hands and feet, digits and all.

This is where a specimen of an ancient lobe-finned fish called Elpistostege watsoni enters the picture. It’s a type of tetrapod-like fish belonging to an order called Elpistostegalia, on the ancestral line that leads to tetrapods; our understanding of the emergence of tetrapods largely relies on what we know about that order.

(Cloutier et al., Nature, 2020)

But the elpistostegalian fossil record has been pretty scarce, with incomplete pectoral fin skeletal anatomy. Until 2010, when an almost complete 1.57-metre (5.15-foot) fossilised E. watsoni skeleton was found in the Escuminac Formation of Miguasha in Quebec, Canada.

Long and his colleague palaeontologist Richard Cloutier from Universite du Quebec a Rimouski in Canada have been carefully studying the fossilised bones to see what they can tell us about this mysterious animal. This paper is the first in a series, and it describes how the pair and their team used CT scanning to discover the skeletal anatomy of the fin.

“We focused on the discovery of digit bones in the fin as this was a really spectacular discovery – the first definite (not controversial) case of a fish with finger bones,” Long told ScienceAlert.

“Once we had compared our fin skeleton of Elpistostege with the arm and hand skeletons of terrestrial animals, it became clear that the rows of small digit bones were – in the evolutionary sense – the same as to phalange bones in the hands of land animals (like us).”

anatomy of the fish fingers chartComparison of early tetrapod limb anatomy. (Richard Cloutier and John Long)

The bones are not exactly true fingers, since they’re tucked inside the fin like a mitten, and can’t move freely. The fin still retains the outer fringe covered in fin-ray bones, called lepidotrichia; the fingers wouldn’t be able to move freely unless E. watsoni lost those.

But it does confirm the animal as an intermediate between fish and tetrapods. Although some have thought digits and carpals may be unique to tetrapods, we have had hints otherwise; for instance, the tetrapod-like arrangement of humerus, radius and ulna bones was discovered in lobe-finned fishes all the way back in 1892.

“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. The increased number of small bones in the fin allows more planes of flexibility to spread out its weight through the fin,” Cloutier explained.

“The other features the study revealed concern the structure of the upper arm bone or humerus, which also shows features present that are shared with early amphibians. 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.”

The next part of the team’s work describing the fossil will focus on the head and parts of the skull, making comparisons with early tetrapods to further trace those evolutionary connections.

“It’s a truly amazing specimen indeed,” 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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