Marine bacteria light up to get a ride elsewhere.

More than a half-century ago, researchers at the Beltsville Agricultural Research Center outside Washington, D.C., engaged in some creative barnyard breeding. Their goal was the development of fatherless turkeys — virgin hens that would reproduce via parthenogenesis. Along the way, and ostensibly quite by accident, an interim stage of this work resulted in a rooster-fathered hybrid that the scientists termed a churk.

Scientists find that a mouse’s heart swells in the presence of python blood

In the wild, the most powerful males reign tensely.