Difference (from prior major revision)
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Changed: 11c11
The last 20 years have seen an explosion in scientific research into the genetic, biological and psychological causes of homosexuality.
The last 20 years have seen an explosion in scientific research into the genetic, biological and psychological causes of homosexuality. Most research looks at human sexuality, but homosexual behavior has been observed in non-human animals as well as in humans.
Changed: 25c25
Homosexual behavior has been observed in non-human animals as well as in humans.