Item – Theses Canada

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OCLC number
46952568
Author
Muir, Cedric Campbell,1963-
Title
The descendants of our ancestors : investigating population structure of the orangutan, Pongo pygmaeus, using DNA sequence and paleomigration modeling.
Degree
Ph. D. -- Simon Fraser University, 1998
Publisher
Ottawa : National Library of Canada = Bibliothèque nationale du Canada, [1999]
Description
2 microfiches.
Notes
Includes bibliographical references.
Abstract
Up until 40 000 years ago, the orangutan ('Pongo pygmaeus') ranged widely over South Asia. Sea level fluctuations which have resulted from numerous glacial advances have given rise to widespread landbridge formation between the islands of Borneo, Sumatra, and Java, with the South Asian mainland. Compilation of a sea level change series over a bathometric matrix was used to create a video which demonstrates changes in the land form resulting from glacial induced sea level fluctuations. Land bridges which existed provided possible migration routes between dernes which presently share alleles. Thirteen mitochondrial and nuclear loci were sequenced and compared between up to 41 individuals from different sample areas. Phylogenetic analysis of these data indicate recent gene flow between some sample areas including presently distinct islands of Borneo and Sumatra. Rates of sequence evolution were compared across mitochondrial and nuclear loci including a (mt) gene/(nuc) pseudo-gene pair. Coalescent theory, and a derivation from this theoretical framework, were engaged to infer which alleles are most like the ancestral state which contextualizes a paleornigratory hypothesis to explain contemporary allele distribution. Gene trees were constructed as cladograms which allow extant taxa to occupy internal nodes and are consistent with the paleomigratory model. Continued habitat destruction contributes, both directly and indirectly, to important declines in the overall numbers of orangutans as well as fragmenting remaining populations. Large clear-cut swaths may also limit gene flow between areas which have shared migrations.
ISBN
0612377350
9780612377356