spe·ci·a·tion /ˌspiʃiˈeɪʃən, -siˈeɪ-/ Pronunciation Key - Show Spelled Pronunciation[spee-shee-ey-shuhn, -see-ey-] Pronunciation Key - Show IPA Pronunciation
–noun Biology.
the formation of new species as a result of geographic, physiological, anatomical, or behavioral factors that prevent previously interbreeding populations from breeding with each other.
spe·ci·a·tion (spē'shē-ā'shən, -sē-) Pronunciation Key
n. The evolutionary formation of new biological species, usually by the division of a single species into two or more genetically distinct ones.
http://dictionary.reference.com/browse/speciation