To find out which linguistic features travel together, and might thus be parts of Chomskyan modules, means drawing up a reliable linguistic family tree.

ECONOMIST: The evolution of language: Babel or babble? | The

And various other features of hominids' skulls also hint at linguistic ability.

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It looks, then, as if the correlations between grammatical features noticed by previous researchers are actually fossilised coincidences passed down the generations as part of linguistic culture.

ECONOMIST: The evolution of language: Babel or babble? | The