Dinosaurs went extinct 65 million years ago
Not wrong, but our understanding became significantly more precise.
TaughtDinosaurs ruled the Earth and then went completely extinct 65 million years ago. Birds may be distantly related to them.
NowBirds are dinosaurs, not relatives of dinosaurs. Non-avian dinosaurs died out about 66 million years ago, but the group survives: there are roughly 11,000 living dinosaur species.
What actually happened
Under modern cladistics, a group includes all descendants of a common ancestor, and you cannot evolve out of your ancestry. Birds are nested inside theropod dinosaurs, the same branch that contains Velociraptor and Tyrannosaurus. That makes them dinosaurs in exactly the way that you are a mammal, not a mammal relative.
The supporting evidence piled up through the 1990s: feathered non-avian dinosaurs from China, wishbones, hollow bones, brooding postures preserved in fossils, and even soft-tissue and protein fragments. Two smaller corrections ride along. The date drifted from 65 to about 66 million years ago as dating improved. And the phrase to use is "non-avian dinosaurs" when you mean the ones that died. There is a pigeon outside doing fine.
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Sources
- American Museum of Natural History: Are birds dinosaurs?amnh.org
- Smithsonian: The origin of birdsnaturalhistory.si.edu
Who was taught this
Still standard through 2000, so anyone who finished school between 1950 and 1996 learned the earlier version.