cnidaria

03/05/2012 - 15:53

New research from the University of California shows how the ability to detect light could have evolved before anything like an eye.  As published today (March 5) in the journal BMC Biology, the research is based on the stinging mechanism in the tiny, brainless and eyeless freshwater polyp Hydra magnipapillata. Part of a group of animals called cnidarians that includes sea anemones, corals and jellyfish, a hydra is essentially a mouth surrounded by tentacles armed with stinging cells, or cnidocytes.