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Primary sensory cortices of microphthalmic mammals, adaptations to habitat and lifestyle
Miklušová, Zuzana ; Němec, Pavel (advisor) ; Druga, Rastislav (referee)
Microphthalmia has evolved in evolution many times independently within unrelated groups of mammals (e.g., rodens, echolocating bats, shrews). Due to such extensive convergent evolution, investigation of mammals with reduced eyes provides a unique approach for understanding the adaptive significance of sensory regression, the impact of peripheral reduction on organization of central sensory structures and cross-modal reorganization or compensation. In this thesis I review our current knowledge concerning the organization of the primary sensory cortex in microphthalmic mammals. In subterranean species (the eastern mole, Scalopus aquaticus; the star-nosed mole, Condylura cristata; the blind mole rat, Spalax ehrenbergi; the naked mole rat, Heterocephalus glaber) is obvious expansion of somatosensoty cortex, which processes tactile information.The sense of touch plays a pivotal role in orientation in their dynamically changing three-dimensional burrow systems. Microphthalmic, echolocating bats whose body is adapted to flight have topographicly reorganized somatosensory cortex, reduced the visual cortex and expanded, complexly organized acoustic cortex. Terrestrial shrews (Soricidae, Insectivora) do not posses any specific adaptations at level of the sensory cortex. Interestingly, their primary visual cortex is...
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