It’s nearly impossible to know how extinct animals behaved; there’s no Jurassic Park where we can watch them hunt or mate or evade predators. But a developing technique is giving researchers a physiological cipher to decrypt the behavior of extinct species by reconstructing and analyzing extinct animals’ proteins. This molecular necromancy can help them understand traits that don’t preserve in the fossil record.
In the most recent example of this technique in action, scientists led by Sarah Dungan, who completed the work while a graduate student at the University of Toronto (U of T) in Ontario, have revived the visual pigments from some of cetaceans’ earliest ancestors. The work has given Dungan and her colleagues a new look into how proto-cetaceans would have lived in the immediate aftermath of a crucial evolutionary juncture: the time roughly 55 to 35 million years agowhen the animals that eventually became whales and dolphins abandoned their terrestrial lifestyles to return to the sea.
Dungan’s fascination with whale evolution began when she was eight. As a kid, she loved spending time in the water and learning about marine biology. Her dad told her in passing that the ancestors of modern whales once lived on land. The notion that an animal could transform from living entirely out of water to not being able to live outside it stuck with her. Learning about the evolutionary transition modern whales took—from ocean to land and back again—“totally blew me away,” she says. “The paper is the end of a story that started when I was really young.”
In 2003, researchers at U of T pioneered a technique to assemble extinct animals’ ancient visual proteins. They’ve applied the technique across the animal kingdom, learning more about how extinct species saw the world. But studying extinct cetaceans is especially interesting because the land-to-ocean transition transformed the animals’ visual realms.
In this study, the researchers compared rhodopsin, the visual pigment responsible for dim-light vision, from the animals that bookended the land-to-ocean transition. They focused on the first cetacean, which lived 35 million years ago and probably swam using powerful muscles in its tail, and the first whippomorph (one of a group of animals that includes cetaceans and hippos), which lived 55 million years ago.
Scientists haven’t discovered the fossils for the two extinct species yet. For that matter, they can’t even say precisely what species they are. But Dungan’s technique can infer ancient protein sequences even without this information. The approach follows the evolutionary breadcrumbs left in modern animals’ proteins to figure out what the ancient forms would have looked like, even without the bones of the species themselves. By comparing the presumed proteins of the first whippomorph and the first cetacean, the scientists can glean the subtle differences in their vision. These differences in vision could reflect differences in the animals’ behaviors.
“There’s only so much you can learn from fossil evidence,” Dungan says. “But the eye is a window between the organism and its environment.”
Using an evolutionary tree and the known rhodopsin structures from modern cetaceans, Dungan and her team built a model to predict the ancient animals’ variants. They manufactured the visual pigments in the lab by genetically modifying cultured mammalian cells and tested the light they are most sensitive to. The scientists found that compared with the ancient whippomorph, the extinct cetacean was likely more sensitive to blue wavelengths of light. Blue light penetrates deeper into water than red, so modern deep-sea denizens, including fishes and cetaceans, have blue-sensitive vision. The finding suggests the extinct cetacean was comfortable in the deep sea.
The scientists also found that the ancient cetaceans’ version of rhodopsin adapts quickly to the dark. Modern cetaceans’ eyes quickly adjust to dim light, helping them move between the bright surface where they breathe and the dark depths where they feed. This finding is “what really sealed the deal,” Dungan says.
Based on their findings, the scientists think early cetaceans probably dove to the ocean’s twilight zone, between 200 and 1,000 meters. Eyesight was vital during dives. Ancient cetaceans couldn’t echolocate like dolphins, so they relied more heavily on vision.
The finding is surprising, says Lorian Schweikert, a neuroecologist at the University of North Carolina Wilmington who wasn’t involved in the study. She thought the first cetaceans would have stayed near the surface. “Started from the bottom now we’re here,” she jokes, alluding to Drake’s hit song.
Schweikert says that studying eye physiology is a reliable way to infer an animal’s ecology because visual proteins don’t change much over time. The rare changes almost always correlate with environmental shifts.
The most important conclusion of Dungan and her colleagues’ work, says Schweikert, is that it further clarifies the order in which cetaceans’ extreme diving behaviors evolved. The rhodopsin research builds on earlier work that painted a similar picture. In a previous study, researchers reconstructed ancient myoglobin and showed that early cetaceans “supercharged” their muscles’ oxygen supply while they held their breath—further evidence that they were capable divers. Another study, this time on ancient penguins, showed that when the birds had their own transition to marine life, their hemoglobin evolved mechanisms to more efficiently manage oxygen.
Dungan and her colleagues are now channeling their molecular Ouija board to resurrect rhodopsin from the earliest mammals, bats, and archosaurs. This will help them understand how nocturnality, burrowing, and flight evolved.
The approach is “just really fun,” Schweikert says. “You’re trying to look into the past to understand how these animals evolved. I love that we can look at vision to solve some of these problems.”
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.
