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What Did the Ancient Whale See? – Hakai Magazine

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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 ago when 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.”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

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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