How did dinosaurs get so large?
This produced abundant plant life, and herbivorous dinosaurs may have evolved large bodies partly because there was enough food to support them. But being large also helps to protect against predators. The giant sauropods had to eat plants as fast as they could, to grow big enough to be safe from carnivores like T.
Why were dinosaurs so big and we aren t?
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).
Is oxygen the reason dinosaurs were so big?
Some paleontologists speculated that oxygen might be behind the evolution of huge dinosaurs, too, but the hypothesis has been totally undermined by evidence from the geological record and dinosaur anatomy.
Why were dinosaurs bigger than mammals?
For example, we humans need to maintain a temperature of 98.6 degrees Fahrenheit, or 37 degrees Celsius, in order to stay alive. But dinosaurs, like today's reptiles, did not regulate their body temperature, and the extra energy allowed them to grow larger, Smith said.
Why did T rex have small arms?
Though both dinosaurs were only distantly related, they both had enormous bodies with oversized heads and vastly undersized arms. The idea is that as the predators' heads and bodies got bigger, their arms got correspondingly smaller, perhaps to help them balance.
Did any large dinosaurs survive?
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.
Did humans not coexist with dinosaurs?
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.
Could humans breathe the air 65 million years ago?
A long time ago, before humans, dinosaurs, plants, or even bacteria, Earth's air had no oxygen. If we could time travel to that period, we would need space suits to breathe. Scientists think the air was mostly made out of volcanic gases like carbon dioxide.
Will animals ever get as big as dinosaurs?
The bad news is, we are probably not going to see land mammals the size of Brachiosaurus. After the demise of the dinosaurs, mammals did begin to grow larger all over the world, filling a niche left by the big scaly monsters.
Why did mammals survive but not dinosaurs?
"Even if large herbivorous dinosaurs had managed to survive the initial meteor strike, they would have had nothing to eat," he explains, "because most of the earth's above-ground plant material had been destroyed." Mammals, in contrast, could eat insects and aquatic plants, which were relatively abundant after the …
Was the T. rex muscular?
Tyrannosaurus rex, whose name means “king of the tyrant lizards,” was built to rule. This dinosaur's muscular body stretched as long as 40 feet—about the size of a school bus—from its snout to the tip of its powerful tail. Weighing up to eight tons, T. rex stomped headfirst across its territory on two strong legs.
Why was T. rex so bulky?
Scientists have previously shown that T. rex got so big by going through a huge teenage growth spurt, but they didn't know if that was true for just tyrannosaurs, just them and their close relatives, or perhaps all big bipedal dinosaurs.
Why did crocodiles survive but not dinosaurs?
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.
Would humans exist if dinosaurs didn’t go extinct?
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. So perhaps we would not have been here if it weren't for this extinction event 65 million years ago.
What does the Bible say about dinosaurs?
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.
Could dinosaurs survive today?
Background: Factors in Dinosaur Survival
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.
When did the Earth have 35 oxygen?
around 350 million years ago
The Age of Oxygen (400 million to 290 million years ago)
Oxygen made up 20 percent of the atmosphere—about today's level—around 350 million years ago, and it rose to as much as 35 percent over the next 50 million years.
Was there oxygen 1 billion years ago?
For Earth's first 2 billion years, no oxygen existed in the atmosphere. Low levels of oxygen first appeared when cyanobacteria, also called blue-green algae, began releasing oxygen as a byproduct of photosynthesis. Then, about 2.4 billion years ago, Earth underwent the Great Oxidation Event.
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