Laser scanning confocal micrograph of a water flea, Daphnia atkinsoni. This specimen has a "crown of thorns," a defensive trait induced in offspring only when the
parents sense chemical cues released by one of their main
predators, the tadpole shrimp Triops cancriformis. The water flea's exoskeleton (exterior structure, green) and subcellular details within the organism (nuclei - tiny blue dots) are both visible. First Prize, 2009 Olympus BioScapes
Digital Imaging Competition®.