Heat-Seeking Missiles: Sperm may follow rising temperature to egg
By John Travis
As a blast of Arctic air chills much of the United States this winter, many people travel long distances seeking warmth. Much like sperm, apparently.
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A new study suggests that rabbit sperm find their way toward an unfertilized egg by heading toward higher temperatures within the animal’s fallopian tubes. The egg rests at a spot slightly warmer than the site where sperm begin the final leg of their journey, and sperm can sense that temperature difference, report Michael Eisenbach of the Weizmann Institute of Science in Rehovot, Israel, and his colleagues in the February Nature Medicine.