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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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Red Deer-area boy discovers ancient shark's tooth in his yard – Red Deer Advocate

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A dinosaur-loving Red Deer-area boy found a 60 million-year-old fossilized shark tooth — right in his own front yard.

Max Maurizio, 7, was exploring gravel near his house on an acreage southeast of Red Deer on Monday, when he spotted something that didn’t look like other rocks. It was sharp at one end and about an inch and a half long.

“He came running into the house saying, ‘I found a tooth! I found a tooth!” recalled his mom, Carly Maurizio.

At first, Max’s parents assumed it came from one of their cats. But Carly carefully examined it and decided, “‘it looks pretty old…”

Intrigued by Max’s discovery, his dad, Claudio Maurizio, emailed a photo of the tooth to the world-renowned Royal Tyrrell Museum of Palaeontology in Drumheller.

On Tuesday, an emailed response arrived from the museum. The photo had been passed on to Dr. Don Brinkman, an expert on fossil fish and turtles.

Brinkman believes the fossilized tooth very likely belonged to the genus Scapanorhynchus — a type of extinct ancient shark with an elongated snout, whose closest living relative is the goblin shark.

“That is an interesting find,” stated Brinkman in the email.

Scapanorhynchus reached a length of about three metres and was a fully marine animal, “so it is a little unusual getting it in the Red Deer area. However, I have seen a tooth of this genus from exposures of the Horseshoe Canyon Formation in the Tolman Bridge area,” east of Trochu, wrote Brinkman.

He noted rocks around Red Deer are from the Paskapoo Formation and are about 60 million years old.

From 100 million to 66 million years ago, the Prairies were covered by a warm inland sea. Scientists believe this Western Interior Seaway extended 3,000 km, from the Arctic Ocean to the Gulf of Mexico, was 1,000 km wide and 700 metres deep.

The ancient water body contained a wide array of life, including sharks, bony fish, marine reptiles, birds, snails, ammonites and other mollusks.

The Maurizio family appreciates the information the museum provided on the tooth.

Max is particularly thrilled by his find and wants to become a paleontologist someday, said Carly.

Claudio noted his son is always noticing things that other people don’t. Once, before heading on a nature walk with his grandfather in Ontario, Max predicted he would find a bone — and sure enough, he did discover a small piece of wild animal bone, recalled his father.

Since Max has always been fascinated by dinosaurs, the whole family, including younger brother Meyer, regularly camp at Drumheller and visit the museum at least once a year, said Carly.

“Even when we go on little hikes or regular walks, Max is always looking down at the ground, looking for fossils… It’s quite remarkable that they can be found literally anywhere, even in your own yard,” she added.



lmichelin@reddeeradvocate.com

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Here’s a close up of the ancient shark’s tooth Max Maurizio, age seven, found in his Red Deer County yard. (Contributed photo).

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This solar storm strike on Earth triggered a Mysterious phenomenon called ‘STEVE’ – HT Tech

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On August 7 and 8, an unexpected solar storm event on Earth displayed a mysterious and rare sky phenomenon called STEVE or Strong Thermal Emission Velocity Enhancement. What is it and how can it affect us? Find out.

We have always associated solar storms with aurora displays, damage to man-made satellites, radio blackouts and GPS disruptions, but it turns out that solar storms can trigger more mysterious phenomenons than that. The August 7 and 8 solar storm, which came as a surprise, caused a strange space phenomenon that left even the scientists puzzled. Many reported seeing a bright stream of light across the sky which was not like any aurora even seen. The question that arises now is what was that stunning light and can it affect us somehow?

The event was first reported by SpaceWeather.com which noted on its website, “During yesterday’s surprise geomagnetic storm, hot ribbons of plasma flowed through Earth’s magnetosphere. The name of this phenomenon is ‘STEVE’ — short for Strong Thermal Emission Velocity Enhancement. It was also sighted in Montana and Pennsylvania”.

The mysterious phenomenon to be born out of a solar storm is called STEVE

STEVE was seen in many locations in the higher latitudes of the northern hemisphere and reportedly lasted about 40 minutes to an hour. While not much is known about these purple streams of light, we do know some facts about it.

STEVE is a very recent discovery. It was first observed in 2017 by citizen scientists and aurora hunters in northern Canada, according to Live Science. The purple glow is formed due to excessively hot (more than 3000 degrees Celsius) gas ribbons that move through the magnetosphere of the Earth. These gas ribbons typically move much faster than the air surrounding it and when it comes in contact with the radiation of solar storms, it gives out a band of glowing color. These are different from auroras because they are not caused by solar radiations colliding with atoms of oxygen and nitrogen through a process called refraction.

While this is still a superficial understanding of the chemical and physical activities that are taking place to cause this strange phenomenon, it does make for a stunning view across the sky. As for whether it can affect us, so far no evidence shows that these light displays are in any way harmful for us or the planet.

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Meteor Showers Taking Place Thursday and Friday Night – NorfolkToday.ca

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A meteor shower you won’t want to miss.

Gary Boyle, The Backyard Astronomer, tells us we are currently passing through the dusty debris of Comet 109P/Swift-Tuttle.


It last appeared in 1992, and will return again in 2125.

He said the shower is lasting all night long, but 2 a.m. would be the time to see the most meteor.

The Backyard Astronomer suggested keeping an eye out for other things in the sky, as well.

Boyle added the next large shower will be in mid-December, but this one might be a little warmer to sit outside and watch.

Written by Ashley Taylor

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