What Would Happen To Dinosaurs If They Did Not Become Extinct? - Alternative View

What Would Happen To Dinosaurs If They Did Not Become Extinct? - Alternative View
What Would Happen To Dinosaurs If They Did Not Become Extinct? - Alternative View

Video: What Would Happen To Dinosaurs If They Did Not Become Extinct? - Alternative View

Video: What Would Happen To Dinosaurs If They Did Not Become Extinct? - Alternative View
Video: What If the Asteroid Never Killed the Dinosaurs? | Unveiled 2024, March
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Imagine a world in which an asteroid did not destroy the dinosaurs. What would it be? How could dinosaurs roaming the earth define the present, past and future of mammals like us? We can only have a vague idea of that cataclysm, substantially supported by imagination. When the 15 km wide asteroid crashed into Earth about 66 million years ago, it struck with a force equivalent to the 10 billion bombs dropped on Hiroshima. A radioactive fireball incinerated everything for hundreds of kilometers around in all directions and raised a tsunami that spread across the entire globe. The atmosphere itself began to burn, and not a single land animal weighing more than 25 kilograms survived; then 75% of all species became extinct. The so-called non-avian dinosaurs had no chance of survival, only the feathered dinosaurs we know today as birds.

But what if history had taken a different path? What if the asteroid hadn't hit or arrived a few minutes earlier? Such a scenario was proposed by scientists in the recently released BBC documentary "The Day the Dinosaurs Died" (The day the dinosaurs died). These scientists, including Sean Gallick of the University of Texas, argue that if the asteroid arrived a little earlier or a little later, and did not hit the murky waters of the Yucatan Peninsula in Mexico, it would fall into the deep Pacific or Atlantic Ocean, it would absorb some of the impact and reduced the release of sulfur-rich sediments that choked the atmosphere for months or years.

If this were the case, catastrophes and extinctions would still happen, but the largest dinosaurs would survive. Pondering the progress of this alternate timeline is an intriguing thought experiment that paleontologists love to speculate about. Would dinosaurs stay to this day? What new types of dinosaurs could appear? Would dinosaurs get human-level intelligence? Would mammals stay on the planet and still be in the shadows like dinosaurs? Would there be people? Would you evolve? Find a way to coexist with dinosaurs?

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Some scientists argue that even without the asteroids, the reign of the dinosaurs might have ended. “I take a slightly unorthodox view that dinosaurs were doomed anyway because of the cooling climate,” says Mike Benton, a paleontologist at the University of Bristol in the UK. "They would have lasted until the end of the Cretaceous, but we know that mammals evolved and the dinosaur population declined over 40 million years." Benton believes that mammals would have replaced dinosaurs. In 2016, he wrote a paper in which he suggested that dinosaurs were slower than mammals, and this would be the reason for the replacement of species.

Other experts think otherwise. Carnivorous dinosaur researcher Tom Holtz of the University of Maryland agrees that the 66 million-year-old extinction would still have occurred due to eruptions and massive lava flows, but “once you enter the Paleocene and Eocene, there is nothing to affect general dinosaur biology. In this world of carnivores, dinosaurs would still do great."

Steven Brusatte of the University of Edinburgh adds that dinosaurs have survived perfectly well in a wild variety of environments in an ever-changing climate for 160 million years. “The dinosaurs still adapted well at the end of the Cretaceous period, this hardly means that the group of animals is going to die out, they were just waiting for the asteroid to fall. This group had tremendous evolutionary potential."

Assuming that dinosaurs survived, what factors might have shaped their evolution? Perhaps climate change would be the first major obstacle. An event known as the Paleocene-Eocene thermal maximum, which happened 55 million years ago, caused global temperatures to rise 8 degrees above today's elevation, and rainforests covered most of the planet.

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In this greenhouse world with abundant vegetation, it could well be that long-necked sauropods would develop faster, multiply at a more tender age; "Dwarf" sauropods (slightly larger than a cow) were already on the European islands in the late Cretaceous period. The largest titanosaurs of mid-Cretaceous South America - 40-meter creatures weighing several jets - have long since died.

Another trend of the late Cretaceous period was the flourishing of flowering plants, or angiosperms. During the Jurassic period, most plants were ferns and gymnosperms (including ginkgo, cicadas, and conifers). They are generally less nutritious than angiosperms, and the sheer size of sauropods may be due to the processing time and gut size required to efficiently digest such food.

“If plant evolution continued as it does in our modern world, herbivorous dinosaurs would almost certainly have a diet of flowering plants,” says Matt Bonnan, a paleontologist at Stockton University in New Jersey. "Given that they are easier to digest, perhaps a general decrease in body size should be expected … the giant Mesozoic dinosaurs could have disappeared."

Along with flowering plants, fruits appeared that developed along with mammals and birds, helping plants to scatter seeds. Could monkey-like dinosaurs emerge under such conditions, taking advantage of this resource, as primates do today? “Many birds eat fruit. It turns out that many non-avian dinosaurs could adapt to a fruit-based diet,”Bonnan says.

Brusatte agrees that some "small feathered dinosaurs may have followed the path of the primates," as some of them have already split off in the branches. Others might be addicted to nectar, carrying pollen from flower to flower as they absorb food.

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Another important event that happened about 34 million years ago on the border of the Eocene and Oligocene was the separation of South America and Antarctica. This led to the emergence of circumpolar currents, which led to the formation of the Antarctic ice cap and the cooling and drying of the world. During the Oligocene and at the end of the Miocene, meadows spread over large areas of the planet.

"Lean, fast-running, herbivorous mammals are commonplace - in the past, you could jump and hide, but you can't hide in open meadows," Holtz says. It was then that our history saw a surge in the development of ungulates, grazing animals and the predators that pursued them.

Darren Nish, a vertebrate paleontologist in Southampton, UK, says that perhaps in our alternate universe, fast, herbivorous dinosaur equivalents would be the descendants of the horned relatives of Triceratops or bipedal, beak-like herbivores similar to hipsilophodon.

“Dinosaurs have already come with a huge array of evolutionary advantages that have taken mammals a long time to develop,” he adds, so adaptation to grasslands would be off the ground. Duck-like Garosaurs had batteries of thousands of teeth, whereas our horses have 40 teeth, so chewing on grass would not have been particularly difficult for them.

Dinosaurs also had better eyesight than mammals, a wider color gamut, and perhaps a better eye for danger. Horses and cows have flattened muzzles suitable for chewing on low-lying vegetation, so platypuses and sauropods might develop flattened noses, and sauropod necks might shrink to allow them to pick up food under their feet.

As we approach today, dinosaurs have had to deal with various ice ages over the past 2.6 million years. But we do know that the Cretaceous dinosaurs lived above the Arctic Circle. “Perhaps in cooler places, you would see thick and thick hides covered with down and feathers, down to the tips of the toes and tails,” says Nish.

"Dromaeosaurs or even velociraptors would have no problem evolving into woolly tyrannosaurs," adds armored dinosaur expert Victoria Arbor of the Royal Ontario Museum in Canada. "Perhaps we could even have furry and woolly ceratopsians, ankylosaurs, or hadrosaurs."

There are other adaptations that are common today but rarely seen in dinosaurs. For example, burrowing, says Paul Barrett, a paleontologist at the Natural History Museum in London. "It's weird that dinosaurs didn't actually do this, since it's a common way of life among lizards and snakes." Given more time, some dinosaurs could become underground specialists - the scaly or feathered equivalents of earth-moving mammals.

The oceans are another kingdom poorly explored by dinosaurs. Species like Spinosaurus were associated with estuarine and fluvial environments, and reinforced ankylosaurus were often found fossilized in marine sediments and lived along coastlines. Could a spinosaurus or ankylosaurus have traveled the path of mammalian whales and made it to the sea completely? They might even return to land to lay their eggs or even breed young in the sea, as did ichthyosaurs and plesiosaurs.

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What would happen to mammals and birds in a world in which dinosaurs roam on land, pterosaurs fly in the sky, and ichthyosaurs and mosasaurs are found in the sea?

In the Late Cretaceous period, there were already a lot of birds. “The diversity of pterosaurs has really diminished,” Holtz says, perhaps because of this. The massive toothless azhdarchids remained, some of which were the size of biplanes with a wingspan of 12 meters. It was even believed that some Azhdarchids did not fly at all, and it is even easier to imagine a world in which strange land pterosaurs dominate on islands like Madagascar, Mauritius and New Zealand, just as our world once saw elegant dodos and giant moas.

Nish argues that the dinosaur world would still have a wide variety of birds. But mammals are a whole different story. Although they had been around for maybe even 160 million years when the asteroid hit, they were "marginal, shadow-dwelling creatures," says Brusatte, diverse but small and tied to specific niches. “It was only the shock of the asteroid impact that killed the domineering dinosaurs that set them free,” he says.

Not everyone agrees with this point of view. They believe that while a large megafauna may not have had a chance, bats, rodents and primates should have developed and thrived. If monkeys, langurs and gibbons were jumping on branches, and dinosaurs roaming among them, wouldn't something akin to hominids appear?

“Some mammalian pedigrees were already evolving prior to extinction,” says Nish. “Because of this, you will most likely still get primates and some version of humanity, which is also possible. Considering that we all evolved in a world full of giant mammals, this is plausible."

Holtz agrees that this is possible: “There might be some climbing primates who, along with the expansion of the meadows, would move into this habitat and become pseudo-humans of this alternate universe. And just as our ancestors had to deal with saber-toothed cats and great antelope, these guys had to deal with dromaeosaurs and abelisaurs."

Humans would have had to create sheltered places, according to Nish, that “would have taken a million years of evolution to create,” but our ancestors lived next to large dangerous animals and learned to survive. "People think the Mesozoic world is a constant bloody battle where you get ripped to shreds in a few seconds, but for the most part the predators are highly distributed and the world is relatively safe."

Given that intelligent mammals are possible, could intelligent dinosaurs emerge as well? In 1982, Dale Russell, who worked at the Canadian Museum of Nature in Ottawa, published a document in which he outlined that an intelligent "dinosauroid" could one day appear. He even created a life-size model, which by today's standards would seem completely alien, with green skin and big eyes. His theory was based on the fact that the carnivorous dinosaur Troodon had an unusually large brain and could have laid the foundation for a lineage of brainy dinosaurs.

"Crow, parrot, or primate-like dinosaurs could have emerged, with complex brains and problem-solving skills," Holtz agrees, but doesn't believe dinosaurs would ever be like humans. "The path of humans was very strange and started with trees and vines, and dinosaurs were bipedal for other reasons."

“It’s unlikely that we would get something that is close in intelligence to a person,” says Nish. "There could be smart dinosaurs with big brains, but they will still be dinosaurs … It's anthropomorphic to suggest that other kinds of human intelligence might have evolved."

Assuming that dinosaurs did live for the last hundreds of thousands of years and even met humans, can we assume that they would have survived to this day? It seems that yes. But as humans destroyed mammoths and other megafauna, they would inevitably start hunting dinosaurs as well. “The extinction could have happened in the Pleistocene as humans spread to all corners of the globe,” Holtz says.

At this time in this alternate timeline, it is possible that several species of large herbivorous sauropods and even carnivores similar to T. rex could exist in protected deserts and national parks suitable for life. Perhaps the smallest non-avian dinosaurs would adapt to urban environments and thrive with humans in cities, along with pigeons, rats, and seagulls.

Ilya Khel

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