It is ironic in that the Morlocks, savage ape-like beings with pale skin and hair (from living underground), seem to be more intelligent than the Eloi, a apparently more evolved peaceful race of people.  The Morlocks, descendents of Britain's working class, make easy prey of the Eloi (by raising them as livestock for their food) who, finally, are docile to the point of being dull-witted and servile. This is a direct stab at the Darwinist theory of evolution in that some radical changes over time aren't really improvement for the species in question.

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