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:format(jpeg)/cdn.vox-cdn.com/uploads/chorus_image/image/50042261/Screen_20Shot_202016-07-06_20at_206.0.jpg "Nettie Stevens discovered XY sex chromosomes. She didn't get credit because she had two X's. - Vox")
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,webp/004/629/832/526x298.8.webp "Xy Sex | xHamster")
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