Deaf children whose access to usable conventional linguistic input, si
gned or spoken, is severely limited nevertheless use gesture to commun
icate(1-3). These gestures resemble natural language in that they are
structured at the level both of sentence(4) and of word(5). Although t
he inclination Ito use gesture maybe traceable to the fact that the de
af children's]tearing parents, like all speakers, gesture as they talk
(6), the children themselves are responsible for introducing language-
like structure into their gestures(7). We have explored the robustness
of this phenomenon by observing deaf children of hearing parents in t
wo cultures, an American and a Chinese culture, that differ in their c
hild-rearing practices(8-12) and in the way gesture is used in relatio
n to speech(13). The spontaneous sign systems developed in these cultu
res shared a number of structural similarities: patterned production a
nd deletion of semantic elements ii the surface structure of a sentenc
e; patterned ordering of those elements within the sentence; and conca
tenation of propositions within a sentence. These striking similaritie
s offer critical empirical input towards resolving the ongoing debate
about the 'innateness' of language in human infants(14-16).