2. (Continued...)

Rumi NeelyOther researchers note that kissing is biology's way of determining who in nature you are most genetically compatible with. "At the moment of the kiss, there are hard-wired mechanisms that assess health, reproductive status and genetic compatibility," says Gordon G. Gallup Jr., a professor of evolutionary psychology at the State University of New York at Albany who studies reproductive competition and the biology of interpersonal attraction." Therefore, what happens during that first kiss can be a make-or-break proposition. [Photo via @rumineely]
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