Meeting Abstract
Environmental variation along a species’ geographic range often imposes strong selection on isolated populations. In the absence of gene flow, populations may become locally adapted, which facilitates population divergence, and potentially speciation. Natural systems in which genetically divergent populations have adapted to different levels of environmental stress allow us to examine the relevance of genetic variation for adaptive evolution of gene networks. Most intertidal organisms experience short-term changes in abiotic factors including temperature, salinity, and dissolved oxygen (DO) in their marine or estuarine habitats. Previous work has shown that T. californicus can withstand prolonged exposure to extreme oxygen deprivation with very little mortality; however, this was assessed in only one population, and it is unknown to what degree allopatric populations along a wide latitudinal range are similarly tolerant. Here, we assess both juvenile and adult response to extreme hypoxia in multiple populations of T. californicus from California to Oregon. Ultimately, we show evidence for population-level variation in tolerance to low DO levels with regards to survival, as well as growth and development.
