New Page 2
About 60 million years ago, something happened to wipe dinosaurs off the face of the Earth. These creatures dominated the landscape far longer than humans have been around, but many mysteries remain about their appearance, physiology and eventual extinction. So which of today's animals evolved from dinosaurs?start quiz
Question 2 of 11
Which of the following is directly related to dinosaurs?
... The prevailing scientific view is that whether you're seeing a hummingbird, a robin, a flamingo or any other type of bird, you're seeing a descendant of dinosaurs.
Question 3 of 11
In what era did dinosaurs live?
... Dinosaurs were a group of land animals that lived about 230 million years ago until about 60 million years ago. This spans the era of Earth's history known as the Mesozoic era, which includes the Triassic, Jurassic and Cretaceous periods.
Question 4 of 11
Which of the following is not a common dinosaur trait?
... Dinosaurs had four limbs, although some of them walked on just two legs.
Question 5 of 11
Which features of a dinosaur fossil indicate that it had feathers?
... Bumps, called quill barbs, on the bones mean the dinosaur had feathers -- some Velociraptor specimens have these barbs.
Question 6 of 11
Which type of medical technology do some researchers use to examine the interiors of dinosaur fossils?
... With computerized axial tomography (CAT) or CT scans, scientists can get a detailed view of inaccessible parts of skulls and other bones.
Question 7 of 11
What is the K-T boundary?
... A popular theory that explains the extinction of dinosaurs at the K-T boundary -- the Alvarez theory -- states that an asteroid may have hit the Earth, causing massive shock waves, debris clouds and devastation. That impact, combined with geological changes and volcanic eruptions, most likely led to extinction of dinosaurs and about 50 percent of other species on Earth.
Question 8 of 11
What is one predominant question scientists have not entirely agreed upon about dinosaurs?
... One lingering question, which encompasses several smaller questions, is whether dinosaurs were warm-blooded, like birds and mammals, or cold-blooded, like reptiles.
Question 9 of 11
Which group of dinosaurs evolved into birds?
... The dinosaurs that evolved into birds are theropods -- the three-toed dinosaurs that include Tyrannosaurus rex and Velociraptor. Ironically, these are members of the saurischian, or lizard-hipped, subgroup, rather than the ornithischian, or bird-hipped, group.
Question 10 of 11
Which factor likely had the greatest influence on the extinction of dinosaurs?
... A popular theory for the extinction of dinosaurs, the Alvarez theory states that an asteroid may have hit the Earth, causing mass extinctions.
Question 11 of 11
Which of the following prehistoric animals technically was not a dinosaur?
... Many of the most well-known prehistoric reptiles, like the pterodactyl, aren't dinosaurs since dinosaurs must technically be four-legged land animals.