ECTOTHERM THAT REGULATES ITS TEMPERATURE BY THE HEAT OF THE ENVIRONMENT (POIQUILOTHERM), BUT THAT IN SOME CASES HAVE OTHER MEANS TO BEHAVE LIKE HOMEOTHERMS. Eye: Not to be confused with ECTODERM, which the outer layer of the metazoan embryo, from which then derives the skin, hair, feathers, nails and nervous system.
