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Repeated evolution: Warm blood evolved multiple times independently
Endothermy, i.e. the endogenous production of metabolic heat, has evolved multiple times among vertebrates, and several strategies of heat production have been studied extensively by physiologists over the course of the twentieth century. The independent acquisition of endothermy by mammals and birds has been the subject of many hypotheses regarding their origin and associated evolutionary […]
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Repeated evolution of compound eyes: one of two seemingly very unlikely evolutionary histories must be true
From PNAS.ORG: These results illustrate exactly why arthropod compound eye evolution has remained controversial, because one of two seemingly very unlikely evolutionary histories must be true. Either compound eyes with detailed similarities evolved multiple times in different arthropod groups or compound eyes have been lost in a seemingly inordinate number of arthropod lineages http://www.pnas.org/content/pnas/99/3/1426.full.pdf These […]
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Repeated evolution: The same retroviral gene coopted independently by unrelated species to aid reproduction
… in other words: a species gets infected by a virus, the virus inserts a part of its own viral-DNA into the species genome. Later on, a very complex placental structure starts emerging in the infected species – and everything is ready for modified reproduction … and, of course, the modified reproduction works flawlessly from […]