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dc.creatorGuerra, Trina Marie
dc.descriptionDue to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to, referencing the URI of the item.en
dc.descriptionIncludes bibliographical references : p. 36-38.en
dc.descriptionIssued also on microfiche from Lange Micrographics.en
dc.description.abstractMitochondrial and nuclear analyses were performed on Phrynosoma cornutum from Texas, New Mexico, and Arizona, to determine appropriate conservation goals f or this threatened animal. Both analyses revealed substantial divergence between Texas populations and those in New Mexico and Arizona. Sequencing of the 950 bp mitochondrial DNA fragment, ND4 to TRNA Leu, revealed an average of 6.25% sequence divergence between individuals from the two regions. Seven microsatellite loci showed strong allelic frequency differences between Texas and New Mexico/Arizona, with Rsr values ranging from 0.613 to 0.966. The divergence seen among P. cornutum populations may be the result of an early Pleistocene pluvial lake, Cabeza de Vaca, that separated populations in Texas from those in New Mexico and Arizona. Several terrestrial vertebrate species have similar distribution patterns in this lake region. The substantial genetic differentiation found between the Texas and New Mexico/Arizona groups warrants classification of P. cornutum into two species. The Texas populations were found to have ample genetic variation despite their threatened status. A lack of geographic differentiation across Texas suggests that conservation efforts, including transplantation and maintenance of populations within the state and regulation of detrimental factors, may be implemented to promote the recovery of P. cornutum.en
dc.publisherTexas A&M University
dc.rightsThis thesis was part of a retrospective digitization project authorized by the Texas A&M University Libraries in 2008. Copyright remains vested with the author(s). It is the user's responsibility to secure permission from the copyright holder(s) for re-use of the work beyond the provision of Fair Use.en
dc.subjectMajor genetics.en
dc.titleGenetic analyses of the Texas horned lizard, Phrynosoma cornutum: implications for conservationen
dc.format.digitalOriginreformatted digitalen

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