Joy Morgan Dey and Nikki Johnson collaborated on an earlier book in which two little bears discover the northern lights.
Both women are nature lovers, and they say books are like agates -- you want to pick them up because there's bound to be something special inside.
Joy Morgan Day says the book came about when Nikki Johnson came to her with a few watercolor sketches of animals.
The book tells the story of Agate, a young brown moose who compares himself with other animals.
The lion is beautiful and strong. The giraffe can see for miles.
The bat "uses his hearing for steering... In a marvel of fine engineering," while Agate the moose feels "clumsy, disjointed and loose."
But at the end, the other creatures help him see that he's just as special as they are. And at that point he changes from a drab brown into a rainbow of vibrant colors.