Centaurs are misshapen, mutated creatures. They are a by-product of the Forced Evolutionary Virus, as they were created by tossing a varied mix of dogs, cats, brahmin and other animals into a FEV vat and seeing what came out the other end.
The Centaur are not only created by the FEV, they also seem to live in an heavy radiated environment. Therefore they radiate everything around them.
Centaurs frequently travel in packs with floaters. They encompassed a large bulk of the masters armies and are commonly found with renegade nightkin and other remnants of the masters army who roam Northern California.
(Falloutwikia ^^)
Und DCs:
Deathclaws are an enormously large, agile, and strong species of genetically engineered reptiles. They are substantially larger than a human, and have large and dangerous claws. It is claimed that they were originally derived from mixed animal stock DNA (mostly Jackson's Chameleons)1 before the Great War to replace humans during close-combat search-and-destroy missions and later refined by the Master, using genetic manipulation2, but the accounts of their origins vary.
Female deathclaws, also called Mothers and Matriarchs, are stronger and tougher than males, as well as fewer in numbers. Only one female is the pack mother at a given time, with another female taking its place when it dies. A pack is led by an 'alpha male'. Although they do not have vocal chords, the deathclaws seem to be able mimic human speech much the same as a parrot does, although normal deathclaws aren't intelligent enough to be capable of real speech.
In 2235, the Enclave captured many deathclaws and exposed them to FEV. This boosted their intelligence, giving them the ability to talk with varying degrees of erudition and articulation. This subspecies was highly intelligent, about the equivalent of an eight-year-old, with some individuals reaching human normal level. Their learning capacity was very high and they were capable of abstract thought and reasoning. Although they did not have vocal chords, the deathclaws seemed to mimic human speech the same as a parrot does. Socially, they had a very rigid code of ethics. They were extremely loyal to the pack as a whole, treating it as a family unit rather than having individual families.
(ganz nachzulesen ebenfalls von dort)