Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
Dolphins have names for one another.
18
In 1918, a homing pigeon saved over 190 American soldiers by delivering a message to nearby support despite having been shot through the breast, blinded in one eye, covered in blood, and with a leg hanging on by just a tendon.
22
When cats are happy, they may squeeze their eyes shut.
10
In Australia, there are spiders big enough to eat snakes.
20
Using a remote-controlled camera, biologists caught dolphins getting high by sucking on puffer fish. They were even caught passing the puffer fish around.
23