Miacis is a small extinct carnivore of the family Miacidae. They were small mammals which lived in forests and climbed trees. They had the ancestral mammalian of about 30-45 teeth. Miacis had brains that were relatively larger than those of the creodonts, and the larger brain size compared to body size suggests their behaviour was more flexible and possibly more intelligent.
Miacids are either early members of the order Carnivora or in a larger group called the Carnivoramorpha. They may not be monophyletic. One professional opinion is that most Miacis species belong to the ancestors of the modern order, the crown-group Carnivora.
The miacids lived 50 to 60 million years ago and was a small omnivorous predator that preyed on smaller animals, such as small mammals, reptiles, and birds, and might have also have eaten eggs and fruits.
- Wesley-Hunt G.D. & Flynn J.J. 2005. Phylogeny of the Carnivora: basal relationships among the Carnivoramorphans, and assessment of the position of 'Miacoidea' relative to Carnivora. Journal of Systematic Paleontology, 3: 1-28. 
- Palmer D. (ed) 1999. The Marshall illustrated encyclopedia of dinosaurs and prehistoric animals. London: Marshall Editions, 214. ISBN 1-84028-152-9