{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/12614"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/12614","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"A functional morphological study of limb regression in some Southern African species of Scincidae (Reptilia : Sauria)","abstract":"How and why did limblessness evolve in certain skinks? These questions are explored in certain species of the Scincidae (from southern Africa) that vary in the degree of limb reduction. This regression series consists of Mabuya capensis (with normal, pentadactyle limbs), Riopa sundevallii (with miniaturized, pentadactyle limbs), three species of the genus Scelotes (bipes, gronovii and brevipes - with vestigial hindlimbs varying in the degree of degeneration) and, finally, Acontias meleagris(without any trace of limbs). The osteology and the myology of the locomotor apparatus are described for all members of this regression series with special reference to the axial system which has in the past received but scant attention compared with the appendicular apparatus. Qualitative and morphometric data are used to construct morphoclines that are correlated with limb reduction. Numerous morphological trends and tendencies support the conclusion that the axial system hypertrophies as the appendages degenerate. The patterns of locomotion are also described for all members of the regression series. Furthermore, an ethocline, that links the limbed and limbless extremes, is postulated. Even in quadrupedal skinks the dominant appendicular system may be assisted by axial flexures that increase stride length. As limbs degenerate, appendicular progression is phased out while axial progression increases in importance.","abstract_html":"How and why did limblessness evolve in certain skinks? These questions are explored in certain species of the Scincidae (from southern Africa) that vary in the degree of limb reduction. This regression series consists of Mabuya capensis (with normal, pentadactyle limbs), Riopa sundevallii (with miniaturized, pentadactyle limbs), three species of the genus Scelotes (bipes, gronovii and brevipes - with vestigial hindlimbs varying in the degree of degeneration) and, finally, Acontias meleagris(without any trace of limbs). The osteology and the myology of the locomotor apparatus are described for all members of this regression series with special reference to the axial system which has in the past received but scant attention compared with the appendicular apparatus. Qualitative and morphometric data are used to construct morphoclines that are correlated with limb reduction. Numerous morphological trends and tendencies support the conclusion that the axial system hypertrophies as the appendages degenerate. The patterns of locomotion are also described for all members of the regression series. Furthermore, an ethocline, that links the limbed and limbless extremes, is postulated. Even in quadrupedal skinks the dominant appendicular system may be assisted by axial flexures that increase stride length. As limbs degenerate, appendicular progression is phased out while axial progression increases in importance.","abstract_has_math":false,"creators":["Leonard, Cecil John"],"institution":"Department of Biological Sciences","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Jarvis, J U M"],"committee_chairs":[],"committee_members":[],"year":1979,"date_issued":"1979","date_published":"1979","updated_at":"2026-07-22T22:22:49Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/12614","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Jarvis, J U M"]},{"key":"dc:creator","label":"Author","values":["Leonard, Cecil John"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2015-03-16T10:30:37Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2015-03-16T10:30:37Z"]},{"key":"dc:date.issued","label":"Date","values":["1979"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Biological Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["PhD"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/12614"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Bibliography: leaves 342-359."]},{"key":"dc:description.abstract","label":"Abstract","values":["How and why did limblessness evolve in certain skinks? These questions are explored in certain species of the Scincidae (from southern Africa) that vary in the degree of limb reduction. This regression series consists of Mabuya capensis (with normal, pentadactyle limbs), Riopa sundevallii (with miniaturized, pentadactyle limbs), three species of the genus Scelotes (bipes, gronovii and brevipes - with vestigial hindlimbs varying in the degree of degeneration) and, finally, Acontias meleagris(without any trace of limbs). The osteology and the myology of the locomotor apparatus are described for all members of this regression series with special reference to the axial system which has in the past received but scant attention compared with the appendicular apparatus. Qualitative and morphometric data are used to construct morphoclines that are correlated with limb reduction. Numerous morphological trends and tendencies support the conclusion that the axial system hypertrophies as the appendages degenerate. The patterns of locomotion are also described for all members of the regression series. Furthermore, an ethocline, that links the limbed and limbless extremes, is postulated. Even in quadrupedal skinks the dominant appendicular system may be assisted by axial flexures that increase stride length. As limbs degenerate, appendicular progression is phased out while axial progression increases in importance."]},{"key":"dc:title","label":"Title","values":["A functional morphological study of limb regression in some Southern African species of Scincidae (Reptilia : Sauria)"]}]}],"canonical_facts":{"dc:contributor.advisor":["Jarvis, J U M"],"dc:creator":["Leonard, Cecil John"],"dc:date.accessioned":["2015-03-16T10:30:37Z"],"dc:date.available":["2015-03-16T10:30:37Z"],"dc:date.issued":["1979"],"dc:description":["Bibliography: leaves 342-359."],"dc:description.abstract":["How and why did limblessness evolve in certain skinks? These questions are explored in certain species of the Scincidae (from southern Africa) that vary in the degree of limb reduction. This regression series consists of Mabuya capensis (with normal, pentadactyle limbs), Riopa sundevallii (with miniaturized, pentadactyle limbs), three species of the genus Scelotes (bipes, gronovii and brevipes - with vestigial hindlimbs varying in the degree of degeneration) and, finally, Acontias meleagris(without any trace of limbs). The osteology and the myology of the locomotor apparatus are described for all members of this regression series with special reference to the axial system which has in the past received but scant attention compared with the appendicular apparatus. Qualitative and morphometric data are used to construct morphoclines that are correlated with limb reduction. Numerous morphological trends and tendencies support the conclusion that the axial system hypertrophies as the appendages degenerate. The patterns of locomotion are also described for all members of the regression series. Furthermore, an ethocline, that links the limbed and limbless extremes, is postulated. Even in quadrupedal skinks the dominant appendicular system may be assisted by axial flexures that increase stride length. As limbs degenerate, appendicular progression is phased out while axial progression increases in importance."],"dc:identifier.uri":["http://hdl.handle.net/11427/12614"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Biological Sciences"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["A functional morphological study of limb regression in some Southern African species of Scincidae (Reptilia : Sauria)"],"dc:type":["Doctoral Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["PhD"]},"updated_at":"2026-07-22T22:22:49Z"}