The term often leads into confusion, however, since international compact cars are somewhat larger than their North American equivalents, mostly because no supermini/subcompact size is manufactured by American, Mexican and Canadian car makers up to date.
By the late 1860's, Darwin came to describe this process as the survival of the fittest. This is very different from Lamarck's incorrect idea that the environment altered the shape of individuals and that these acquired changes were then inherited.
It might sound tautological, but fitness is pretty much defined as 'being more likely to survive - and reproduce'; fitness is surviving and survival goes to the fittest. This is a trite way of citing Richard Dawkins' theory of the replicator to describe fitness.