Adaptation can be considered at the species level, but a recent study involving Tigriopus californicus has shown that that may not be sufficient to accurately predict the effects of climate change on a species. Tigriopus californicus has isolated populations scattered through a wide latitudinal range. These populations have great disparities in terms of their thermal tolerance and their ability to adapt to a new thermal tolerance. This data suggests that in order to accurately predict the effects that a changing temperature and climate will have on a species, it is necessary to look at the variance in adaptation potential in different populations of that species.
Phenotypic plasticity and the rate of climate change are important factors in determining if a species will be able to adapt.
- The phenotypic plasticity of species of brown trout are heritable. http://rspb.royalsocietypublishing.org/content/275/1653/2859.full.pdf+html If the rate of climate change is slow enough that organisms at the upper range of tolerance can survive, then there is a chance that the species can adapt over time by inheriting this tolerance. T
- The rate that a species can adapt is related to how drastic of a temperature change it could survive and adapt to. http://rspb.royalsocietypublishing.org/content/275/1635/649.short In the case of T. californicus, the fragmented population means that there is large variation in the species (and thus large potential for adaptation), but lower opportunity for adaptation within the individual populations.
- A greater amount of variation is indicative of a population that can more readily adapt, as evidenced by this article showing that S. franciscamus,a species of sea urchin, is more likely to be able to adapt to increased carbon dioxide levels than the mussel species M. trossulus over the next 50 years.
An organism at the edge of its thermal tolerance may have more difficulty adapting.
- Among congeneric invertebrates, those adapted to the warmest environments are most susceptible to local extinction. In contrast, some Arctic marine ectotherms have lost the ability to adapt to rising temperature. http://jeb.biologists.org/content/213/6/912.long
- The lowering pH of the oceans affects the ability of certain marine organisms to calcify their skeletons.
- Some corals have the ability to up-regulate the pH at calcification, thus increasing calcification rates with relatively low energetic cost. Even though there is some loss of fitness among these coral, those species of coral without this mechanism will be at a disadvantage if ocean pH levels continue to lower.
Evolution and Climate Change in the Oceans
Comments