Are melanistic populations of the Karoo girdled lizard, Karusasaurus polyzonus, relics or ecotypes? A molecular investigation

Date
2011
Authors
Engelbrecht H.M.
Mouton P.L.F.N.
Daniels S.R.
Journal Title
Journal ISSN
Volume Title
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Abstract
It has been proposed that melanism in cordylids evolved in response to a single climatic event and that melanistic populations of Karusasaurus polyzonus are relictual. This study investigates the genetic relationships of melanistic and non-melanistic populations of K. polyzonus along the west coast of South Africa. Thirty-five specimens of K. polyzonus were collected from three 'melanistic'- and eight 'non-melanistic'- sample localities. Partial sequence data were derived for two mitochondrial DNA loci (16S rRNA and nicotinamide adenine dinucleotide dehydrogenase component 2 (ND2)) and analysed using maximum parsimony, maximum likelihood and Bayesian inference. In addition, a haplotype network was constructed using TCS and an analysis of molecular variance (AMOVA) was conducted. The derived topologies were highly congruent and showed that melanistic and non-melanistic populations were interdigitated on all tree topologies and a number of haplotypes were shared between melanistic and non-melanistic specimens. These results suggest that melanistic populations of K. polyzonus are ecotypes, not relics.
Description
Keywords
coastal climatic conditions, Karusasaurus polyzonus, melanism, ND2, Bayesian analysis, climate conditions, coastal zone, lizard, maximum likelihood analysis, melanism, mitochondrial DNA, molecular analysis, parsimony analysis, population genetics, RNA, topology, variance analysis, South Africa
Citation
African Zoology
46
1
African Zoology
46
1
http://www.scopus.com/inward/record.url?eid=2-s2.0-79956134314&partnerID=40&md5=e1d63a133b7804b287521d5b917fbc33
URI
http://hdl.handle.net/10019.1/16692
Collections
Stellenbosch University - Scopus Publications