Alien Wiki: Howlers
It seemed like a good idea to clone endangered species during the late 21st Century and indeed it was. Later developments in genetic science led to the Uplift programme, which took species with a modest degree of sentience and attempted to create full sapience. One such experiment was with baboons and the result, the Howlers, was a mixed success.
The Howlers are certainly intelligent. It became fashionable to breed them and use them for manual labour in the early days of space exploration. However it later became apparent that flaws in the Uplifting process had not created the intelligent but docile, sophonts the scientists believed they had; the Howlers began to develop a taste for human flesh and distinctly psychopathic and violent tendencies.
Across the frontier worlds like Alzir the Howlers ran amok, escaping to isolated societies that then preyed upon the scattered frontier communities. Howlers are baboon like creatures but with some distinctly human traits and a much fuller coverage of fur than their unmodified counterparts.
Cunning and cruel, Howlers have a developed taste for meat, preferring human flesh which they crave above other protein sources.