Cat
From Halopedia, the Halo wiki
The Cat (Latin, Felis silvestris catus) is a member of the Felidae (Feline) family and has been associated with humans for at least 10,500 years at the time of Halo: Combat Evolved. Genetic tests have determined that the modern cat is descended from a species of desert wildcat, domesticated by humans approximately 8,000 BC in Egypt.
Known cats include Jonesy, pet of the UNSC Pillar of Autumn crew member, a cat named Spock [1] onboard the UNSC Spirit of Fire, and a cat rescued off a church roof by Janissary James.[2] Another cat can also be seen in the concept art for Halo Wars, sitting on the bridge of the Spirit of Fire. Also, in Halo 3 and Halo 3:ODST a cat with a bow called a tom cat can be used as your emblem.