Around 240 million years ago, during the Cretaceous period, the earth looked pretty different. It was a time when dinosaurs roamed freely and crocodiles coexisted alongside them. In fact, crocodiles are one of the only animals that are thought to have survived the asteroid that wiped out the dinosaur population.
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.
The research, published in the Journal of Vertebrate Paleontology, found that the Deinosuchus, a lineage of the giant crocodilians from North America, grew up to 33 feet long and “was the largest carnivore in its ecosystem,” in the late Cretaceous period about 75 to 82 million years ago.
The newly-discovered crocodile species roamed Earth during the Late Jurassic epoch, some 148 million years ago. The ancient creature lived alongside giant titanosaurs and other sauropod dinosaurs as well as smaller herbivorous species such as Chilesaurus diegosuarezi.
There are two main reasons crocodiles survived the asteroid that killed the dinosaurs. First, crocodiles can live for a very long time without food. Second, they lived in places that were the least affected when the asteroid hit Earth.
Surviving crocodiles did not change throughout millions of years because they arrived at an equilibrium where they were efficient and versatile enough that they did not need to evolve to exist, reports the Conversation.
An expert in evolutionary biology explains. There are two main reasons. First, crocodiles can live for a very long time without food. Second, they lived in places that were the least affected when the asteroid hit Earth.
In fact, birds are commonly thought to be the only animals around today that are direct descendants of dinosaurs. So next time you visit a farm, take a moment to think about it. All those squawking chickens are actually the closest living relatives of the most incredible predator the world has ever known!
Gigantism in crocodiles has been reported several times in the fossil record. In North America, the oldest body fossil evidence of giant crocodiles is of Deinosuchus at about 82 million years, estimated to have been between eight to 12 metres long.
Based on fossil evidence, the longest crocodile ever to live was a Sarcosuchus imperator, who measured 40 feet long and weighed 17,600 pounds. The largest one ever officially measured was Lolong, who was a saltwater crocodile that measured 20 feet three inches long and weighed 2,370 pounds.
Alligators & Crocodiles: These sizeable reptiles survived–even though other large reptiles did not. Birds: Birds are the only dinosaurs to survive the mass extinction event 65 million years ago.
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.
Australia is home to two species of crocodiles, the Estuarine Crocodile and the Freshwater Crocodile. Both belong to the reptile family Crocodylidae (the 'true crocodiles'), members of the sub-class Archosauria.
The earliest ancestors of the crocodiles evolved around 200 million years ago during the Late Triassic and Early Jurassic.
They existed long before our time, and there are no dinosaurs left today. There are a lot of interesting and fascinating facts about dinosaurs that have been presented in movies and articles about them. We can better understand the history of our planet by studying the stories of dinosaurs.
Ok, first thing: Please tell us that dragons could be real.
"Unfortunately, no, we do not have evidence of dragons on this planet. We do have evidence of very cool extinct animals that were kind of similar to dragons, but no fire-breathing six-legged vertebrates, I'm afraid."
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.
Are there any sea dinosaurs that may still exist? There are no “sea dinosaurs”. Mosasaurs are marine lizards and Plesiosaurs and Ichthyosaurs are Synapsids that are more distant relatives to dinosaurs. That said, none of them survived either.
Humans never lived with dinosaurs like the T-rex, but only birds. Modern humans are much younger and have only evolved recently, around 300,000 years ago.
The tuatara is a reptile the lives (almost) forever and is related to humans.
Humans and the Tyrannosaurus rex are closer on the world's timeline than the T. rex and Stegosaurus.
But despite their size and strength, there are animals that do prey on them. Man appears to be their biggest predator. Big cats like leopards and panthers sometimes kill and eat these big reptiles. Large snakes can also do a lot of damage to alligators and crocodiles.
It was a life-altering event. Around 66 million years ago, at the end of the Cretaceous period, an asteroid struck the Earth, triggering a mass extinction that killed off the dinosaurs and some 75% of all species.
While much of life became extinct during the End-Cretaceous extinction event, including all non-avian dinosaurs, sharks once again persisted.