He and all of the other researchers, however, suspect that more recent dinosaurs even closer to the K-T boundary will be found in the future. For now, however, the 65-million-year-old Triceratops is the world's last known surviving dinosaur.
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.
Other than birds, however, there is no scientific evidence that any dinosaurs, such as Tyrannosaurus, Velociraptor, Apatosaurus, Stegosaurus, or Triceratops, are still alive. These, and all other non-avian dinosaurs became extinct at least 65 million years ago at the end of the Cretaceous Period.
The loss of species included most dinosaurs, but not all. Today's birds are the last of the dinosaurs, descendents of ancestors that didn't just survive this mass extinction, but evolutionarily exploded into thousands of species distributed around the world.
The first ever fossilised remains of a dinosaur that was killed on the day a massive asteroid struck Earth 66 million years ago have been unearthed by palaeontologists. They discovered the leg of a Thescelosaurus – a small herbivore – alongside a fragment of the seven mile-wide space rock that killed it.
rex - a six-ton powerhouse of muscle and teeth and the most famous killer the world has ever known. Its jaws were packed with over 50 teeth, each up to a foot long, and powerful enough to crush a car.
The results of this study, which were based on estimated real global biodiversity, showed that between 628 and 1,078 non-avian dinosaur species were alive at the end of the Cretaceous and underwent sudden extinction after the Cretaceous–Paleogene extinction event.
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.
Crocodiles are not dinosaurs, but both crocodiles and dinosaurs came from the crown group Archosaurs. Archosaurs were reptiles that included birds, crocodiles, pterosaurs, and dinosaurs. Modern-day birds are descendants of feathered dinosaurs, evolving over the last 65 million years.
Most dinosaurs went extinct. Only birds remained. Over the next 66 million years, birds evolved in many ways, which enabled them to survive in lots of different habitats.
Although that would be fascinating, the answer is almost definitely no. While there's only one generation between you and your grandparents – that is, your parents – there are many millions of generations between today's birds and their ancient dinosaurs ancestors.
Bizarre 500-toothed dinosaur
Nigersaurus, you might remember, we named for bones collected on the last expedition here three years ago. This sauropod (long-necked dinosaur) has an unusual skull containing as many as 500 slender teeth.
But how long can humans last? Eventually humans will go extinct. At the most wildly optimistic estimate, our species will last perhaps another billion years but end when the expanding envelope of the sun swells outward and heats the planet to a Venus-like state. But a billion years is a long time.
Dinosaurs roamed the earth for 160 million years until their sudden demise some 65.5 million years ago, in an event now known as the Cretaceous-Tertiary, or K-T, extinction event.
No, a rhino is not a type of dinosaur. A rhino, short for rhinoceros, is an ungulate or hoofed mammal. Dinosaurs, on the other hand, are a group of reptiles classified as archosaurs. With the exception of modern birds all the dinosaurs went extinct about 65 million years ago.
"Not all the dinosaurs died that day, but many dinosaurs did,” said Sean Gulick, a research professor at the University of Texas Institute for Geophysics and coauthor of a study out today in the Proceedings of the National Academy of Sciences.
So, are chickens dinosaurs? No – the birds are a distinct group of animals, but they did descend from the dinosaurs, and it's not too much of a twist of facts to call them modern dinosaurs. There are many similarities between the two types of animal, largely to do with bone structure.
The age immediately prior to the dinosaurs was called the Permian. Although there were amphibious reptiles, early versions of the dinosaurs, the dominant life form was the trilobite, visually somewhere between a wood louse and an armadillo. In their heyday there were 15,000 kinds of trilobite.
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!
The First Humans
One of the earliest known humans is Homo habilis, or “handy man,” who lived about 2.4 million to 1.4 million years ago in Eastern and Southern Africa.
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.
God told Noah, “And of every living thing of all flesh, two of every sort shalt thou bring into the ark, to keep them alive with thee; they shall be male and female” (Genesis 6:19). A few small dinosaurs would have been on the ark. The larger species of dinosaurs were probably young and smaller on the ark.
Paleontologists don't know for certain, but perhaps a large body size protected them from most predators, helped to regulate internal body temperature, or let them reach new sources of food (some probably browsed treetops, as giraffes do today).
If you were to visit Earth about 65 million years ago, during a time called the Paleocene, you would find thick forests where the descendants of mammals that survived the asteroid impact were starting to get big. Triceratops would have been extinct for a million years.
In fact, one of the things that I think about is that if dinosaurs hadn't gone extinct at this time period, the mammals probably wouldn't have had the same opportunity to kind of take over the world. They would not be able to fill all of those ecological niches that those dinosaurs once filled.