Mostly, although there are some handsome pink ones in the Amazon, and of course Orcas are actually dolphins.
no, some may be a light blue, greys, whites, or light pinks.
No, dolphins may not change colours at all.
Dolphins are mammals so they reproduce the same way all mammals do.
a dolphins color is gray
Well, .........you know some food like shrimp, jellyfish, lobster and you get the point right?
Dolphins are vertebrate's. they have back bones the same as humans whales and all other mammal's.
No,it according to the type of dolphin they are
Yes all vampire bats are the same color
GRAY!
grey
it is gray
Yes they are both eukaryotic, as are all animals.
any color you want