You are probably referring to a camel.
it was dry and desert like a very long time ago. i think.
They've been isolated in that desert for so long. An isolated population can develop traits unique to a single region over time (on an evolutionary scale; a very long time).
There are very many animals which live in the desert and there is no single name for them all.
A desert animal will likely be very cautious of other larger animals. They will be foragers for food and water in the dry desert conditions as well.
An penguin is a bird that can take a very long time to develop from an egg to an adult.
A Turtle is definetley the slowest animal because while a turtle moves it takes a very long time to move from places to place.
A very long time ago is how ever long you wish to make it there is no set time for a very long time ago.
The desert is a habitat where it is very rare to find sources of water.
an ant
The long hair will help insulate the animal from the Sun's heat during the day, and keep it warm during the freezing cold of the night. Most deserts' climate is usually either very hot or very cold.
Not for very long. People cannot survive for very long without water, anywhere.
It is the welwitschia