Because dinosaurs have been extinct for 65 million years.
----------------
Why was 6 afraid of 7?
It wasn't. Numbers are not sentient and thus are incapable of feeling fear.
----------------
A horse walked into a bar.
Several people immediately got up and left as they spotted the potential danger in the situation. The bar was closed and animal control was called. The horse was returned to its rightful owner and the bar reopened the next day.
----------------
Why was the little boy crying?
Because there was a frog stapled to his face.
----------------
Why did the little girl fall off the swings?
Because she had no arms.
----------------
What is a pirate’s favourite letter of the alphabet?
None. Historians believe that all pirates would have been illiterate.