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Phenotypic Divergence Despite High Levels Of Gene Flow In Galapagos Lava Lizards (Microlophus Albemarlensis), Mark Jordan, H. Snell, H. Snell, W. Jordan Jul 2011

Phenotypic Divergence Despite High Levels Of Gene Flow In Galapagos Lava Lizards (Microlophus Albemarlensis), Mark Jordan, H. Snell, H. Snell, W. Jordan

Mark A. Jordan

The extent of evolutionary divergence of phenotypes between habitats is predominantly the result of the balance of differential natural selection and gene flow. Lava lizards (Microlophus albemarlensis) on the small island of Plaza Sur in the Galápagos archipelago inhabit contrasting habitats: dense vegetation on the western end of the island thins rapidly in a transitional area, before becoming absent on the eastern half. Associated with these habitats are phenotypic differences in traits linked to predator avoidance (increased wariness, sprint speed, and endurance in lizards from the sparsely vegetated habitat). This population provides an opportunity to test the hypothesis that reduced …


The Influence Of Historical Landscape Change On Genetic Variation And Population Structure Of A Terrestrial Salamander ( Plethodon Cinereus ), Mark Jordan, Douglas Morris, Scott Gibson Jul 2011

The Influence Of Historical Landscape Change On Genetic Variation And Population Structure Of A Terrestrial Salamander ( Plethodon Cinereus ), Mark Jordan, Douglas Morris, Scott Gibson

Mark A. Jordan

Forest loss and fragmentation is expected to shape the genetic structure of amphibian populations and reduce genetic variation. Another factor widely understood to have impacted these same parameters in North America is the range expansion that occurred following glacial retreat at the end of the Pleistocene. The Eastern Red-Backed Salamander (Plethodon cinereus) has been subjected to both processes. In this context, we investigated the historical events that are likely to have shaped genetic variation in this species using a panel of six microsatellite markers screened on individuals sampled across ten localities in northeastern Indiana, USA. We found low genetic diversity …


Historical Fragmentation And Genetic Drift In Populations Of Galápagos Lava Lizards (Microlophus Albemarlensis Complex), Mark Jordan, H. Snell Jul 2011

Historical Fragmentation And Genetic Drift In Populations Of Galápagos Lava Lizards (Microlophus Albemarlensis Complex), Mark Jordan, H. Snell

Mark A. Jordan

No abstract provided.


North American Pollinator Partnership Conference: Public Lands Task Force, Tammy Horn Apr 2011

North American Pollinator Partnership Conference: Public Lands Task Force, Tammy Horn

Tammy Horn

No abstract provided.


Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney Dec 2010

Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney

Ryan Kerney

The concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and …


Feasibility Of Farming Nile Tilapia, Oreochromis Niloticus (L.), In Suboptimal Water Temperature, Ahmed Mustafa, Laura Randolph, Shree Dhawale Dec 2010

Feasibility Of Farming Nile Tilapia, Oreochromis Niloticus (L.), In Suboptimal Water Temperature, Ahmed Mustafa, Laura Randolph, Shree Dhawale

Ahmed Mustafa Dr.

No abstract provided.


Effects Of Indian Herbs On The Modulation Of Stress And Immune Response In Tilapia, Ahmed Mustafa, Brittany Byerley, Paul Mccain Dec 2010

Effects Of Indian Herbs On The Modulation Of Stress And Immune Response In Tilapia, Ahmed Mustafa, Brittany Byerley, Paul Mccain

Ahmed Mustafa Dr.

No abstract provided.


Embryonic Staging Table For A Direct- Developing Salamander, Plethodon Cinereus (Plethodontidae), Ryan Kerney Dec 2010

Embryonic Staging Table For A Direct- Developing Salamander, Plethodon Cinereus (Plethodontidae), Ryan Kerney

Ryan Kerney

This work presents a refined staging table for the direct-developing red-backed salamander Plethodon cinereus, which is based on the incom- plete staging system of James Norman Dent (J Morphol 1942; 71:577– 601). This common species from eastern North America is a member of the species-rich lungless salamander family Plethodontidae. The stag- ing table presented here covers several stages omitted by Dent and reveals novel developmental features of P. cinereus embryos. These include putative Leydig cells and open gill clefts, which are found in lar- vae of metamorphosing species but were previously reported as absent in direct-developing Plethodon. Other features found …