RED-LIGHT DISTRICT Levels of a brain reward compound increased in male fruit flies genetically engineered to ejaculate when exposed to red light when the insects were bathed in the rosy hue.
Avi Jacob/BIU microscopy unit
NEURON NURSERY Roughly the same number of new nerve cells (dots) exist in the hippocampus of people in their 20s (three hippocampi shown, top row) as in people in their 70s (bottom). Blue marks the dentate gyrus, where new nerve cells are born.
M. Boldrini/Columbia Univ.
ANCIENT LIZARD Four-eyed Saniwa ensidens, which lived 50 million years ago, closely resembled the modern monitor lizard Varanus mertensi, shown here with an overlay of the skull of S. ensidens.
A. Lachmann/Senckenberg Gesellschaft für Naturforschung/Digimorph.org