TUESDAY, July 26 (HealthDayNews) -- Our ability to distinguish the sweetness of oranges from the bitter taste of lemons may have evolved as a protection against eating poisonous plants, suggests new genetic research.

An international team of researchers examined the sequence of one of 25 genes that encode bitter taste receptors in the tongue, reviewing the occurrence of the gene in 60 human populations across the world.

By reconstructing the history of the gene, they found evidence that humans' ability to taste bitterness developed through evolutionary selection.

"Detecting signatures of selection for a bitter taste receptor suggests that sensory detection of dangerous foods played an important role at certain times during the course of our evolution," lead author Nicole Soranzo, of the University College London, said in a prepared statement.

The research is published in the July 26 issue of Current Biology.

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