Landmark Study: Dinosaurs Were in Their Prime When Asteroid Hit Earth. A new study provides the strongest evidence yet that the dinosaurs were struck down in their prime and were not in decline, at the time the asteroid hit.
Birds: Birds are the only dinosaurs to survive the mass extinction event 65 million years ago. Frogs & Salamanders: These seemingly delicate amphibians survived the extinction that wiped out larger animals. Lizards: These reptiles, distant relatives of dinosaurs, survived the extinction.
Some species of giant, long-necked sauropod dinosaurs known as Titanosaurs were also living at the time of the mass extinction event. "One of the last ones is Jainosaurus which would have trampled the reddish rocks of India before it even connected with the rest of Asia," Poust said.
Sixty-six-million years ago, a nearly nine-mile-wide asteroid collided with Earth, sparking a mass extinction that wiped out most dinosaurs and three-quarters of the planet's plant and animal species. Now we're learning that the Chicxulub asteroid also generated a massive “megatsunami” with waves more than a mile high.
Darkness caused by dino-killing asteroid snuffed out life on Earth in 9 months. As sunlight dimmed, plants and animals died. The years following the asteroid impact that wiped out non-avian dinosaurs were dark times — literally.
No! After the dinosaurs died out, nearly 65 million years passed before people appeared on Earth. However, small mammals (including shrew-sized primates) were alive at the time of the dinosaurs.
But within just a few years, life returned to the submerged impact crater, according to a new analysis of sediments in the crater. Tiny marine creatures flourished thanks to the circulation of nutrient-rich water.
It is believed that due to the combination of slow incubation and the considerable resources needed to reach adult size, the dinosaurs would have been at a distinct disadvantage compared to other animals that survived the asteroid that struck Earth 66 million years ago.
Evidence suggests an asteroid impact was the main culprit. Volcanic eruptions that caused large-scale climate change may also have been involved, together with more gradual changes to Earth's climate that happened over millions of years.
Although the crater was massive at the time, it has been 66 million years since the asteroid dropped. So today, most of the area is buried under 3,000 feet of limestone. (Bummer.) But even though you can't walk up and see a mammoth hole in the ground, the legacy of the Chicxulub crater is all around.
Variables such as temperature, food sources, and oxygen levels are all factors that might impact dinosaur survival. Because dinosaurs lived in much warmer climates millions of years ago, many experts doubt they could even survive today.
They would not be able to fill all of those ecological niches that those dinosaurs once filled. They would still probably be small, scrawny, and very generalized. But instead, the mammals were able to evolve and diversify and, well, ultimately, millions of years later, become some humans.
For approximately 120 million years—from the Carboniferous to the middle Triassic periods—terrestrial life was dominated by the pelycosaurs, archosaurs, and therapsids (the so-called "mammal-like reptiles") that preceded the dinosaurs.
The arrival of the asteroid 66 million years ago triggered the mass extinction of non-avian (non-bird) dinosaurs, ending the Cretaceous period.
The giant asteroid, believed to be the size of Mount Everest, smashed into the Earth at a point now known as the Chicxulub crater. The impact site sits buried beneath the ocean in the Gulf of Mexico – you can see the exact location on Google Maps at the co-ordinates 21.4,-89.516667.
The productivity of marine ecosystems in the North Atlantic took about 300,000 years to be restored. In the immediate area of the crater, however, life returned more quickly.
According to the Bible, dinosaurs must have been created by God on the sixth day of creation. Genesis 1:24 says, “And God said, Let the earth bring forth the living creature after his kind, cattle, and creeping thing, and beast of the earth after his kind: and it was so.”
Sixty-six million years ago, dinosaurs had the ultimate bad day. With a devastating asteroid impact, a reign that had lasted 180 million years was abruptly ended. Prof Paul Barrett, a dinosaur researcher at the Museum, explains what is thought to have happened the day the dinosaurs died.
Today, paleontologists have discerned that most dinosaur lineages disappeared by about 66 million years ago after intense volcanic activity, climate change and a catastrophic asteroid impact triggered one of the worst mass extinctions in our planet's history.
Today there are at least 11,000 bird species. But with such a close relationship to the extinct dinosaurs, why did birds survive? The answer probably lies in a combination of things: their small size, the fact they can eat a lot of different foods and their ability to fly.
Crocodiles
Well, crocodiles share a heritage with dinosaurs as part of a group known as archosaurs (“ruling reptiles”), who date back to the Early Triassic period (250 million years ago). The earliest crocodilian, meanwhile, evolved around 95 million years ago, in the Late Cretaceous period.
If they didn't die, but instead kept evolving, they may have developed even bigger brains and keener senses. And given millions of years of evolution, perhaps they would have taken the path of primates, eventually developing tool use, sophisticated communication, and even complex societies.
The 'Big Five' mass extinctions
There have been five mass extinction events in Earth's history. At least, since 500 million years ago; we know very little about extinction events in the Precambrian and early Cambrian earlier which predates this.
The First Animals
Sponges were among the earliest animals. While chemical compounds from sponges are preserved in rocks as old as 700 million years, molecular evidence points to sponges developing even earlier.
We'd likely still have those supergiant, long-necked herbivores and huge tyrannosaur-like predators. They may have evolved slightly bigger brains, but there's little evidence they'd have evolved into geniuses. Neither is it likely that mammals would have displaced them.