Genetic variation and thermal tolerance were surveyed for variation attributed to nonuniform selection pressures for five populations of the red shiner, Notropis lutrensis, collected from regulated and unregulated portions of a Texas river. Populations within 30 km of a hypolimnion-release dam that experience large thermal perturbations were found to have higher levels of heterozygosity, higher levels of polymorphism, significantly depressed levels of upper thermal tolerance endpoints, and greater variances in tolerance endpoints. These populations have evolved enzyme systems differing from the unregulated populations in response to a variable and depressed thermal regime.
| Identifer | oai:union.ndltd.org:unt.edu/info:ark/67531/metadc663337 |
| Date | 12 1900 |
| Creators | King, Timothy L. (Timothy Lee) |
| Contributors | Zimmerman, Earl G., Beitinger, Thomas L., Dickson, Kenneth L. |
| Publisher | North Texas State University |
| Source Sets | University of North Texas |
| Language | English |
| Detected Language | English |
| Type | Thesis or Dissertation |
| Format | v, 71 leaves : ill., maps, Text |
| Rights | Public, King, Timothy L. (Timothy Lee), Copyright, Copyright is held by the author, unless otherwise noted. All rights |
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