Survivorship of ploidy-variable unisexual <i>ambystoma</i> aalamanders across developmental stages

<p>Unisexual <em>Ambystoma</em> produce ploidy-variable offspring that differ in survivorship to adulthood. These populations reproduce through kleptogenesis, persisting by stealing genetic material from males of compatible bisexual <em>Ambystoma</em> species (e.g., Jefferson's Salamander <em>A. jeffersonianum</em>, and the Blue-Spotted Salamander <em>A. laterale</em>). Kleptogenesis can result in ploidy-variable embryos within an egg mass because the female may or may not incorporate the male ambystomatid genome. Little is known about the survivorship of ploidy-variable individuals. In previous studies, triploid individuals are the most abundant class, suggesting a greater mortality in high-ploidy (tetraploid and pentaploid) individuals. We assessed the frequency of ploidy levels (determined by microsatellite analysis) across four life stages within a single year: adults, early larvae, late larvae, and metamorphs. We found that, instead of an abrupt change due to individuals dying at or during metamorphosis, there was a gradual decline in tetraploids across all stages as the larvae develop into adults.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Open Access Thesis

Discipline thesis:degree_discipline

Biology

Year dc:date.available

2013

Author dc:creator

• Casto, Christina Marie

Contributors dc:contributor

• Katherine Greenwald, Ph.D., Chair
• Margaret Hanes, Ph.D.
• Steven Francoeur, Ph.D.

• Ambystoma
• Caudata
• larvae
• metamorphosis
• survival
• Kleptogenesis
• Biology

Repository record dc:identifier

https://commons.emich.edu/theses/601

OAI identifier oai:identifier

oai:commons.emich.edu:theses-1980