It turns out that great fitness may mean a greater tolerance when it comes to changing temperatures. Scientists have found that animals that live in smaller elevational range sizes may be more adapted to changing temperatures.
In previous studies, researchers have theorized that animals that are able to endure greater swings in seasonal temperatures tend to have great elevational range sizes. However, this latest study shows that this may not be the case.
In this latest study, the researchers focused on daily temperature changes over those that happen over a season. They used a database of 16,592 species of vertebrae at 180 different elevation points. They input the data into a model with nine variables, including daily temperature variations.
So what did they find? The new analysis confirmed that adaptation to greater seasonal temperature correlates with great elevational ranges. However, the scientists found that the opposite pattern was true in species adapted to higher fluctuations in daily temperatures; this was, instead, associated with smaller elevational distributions. This means that specialist species that inhabit narrower ranges may actually do better in areas where daily fluctuation are dominant. In contrast, generalist species are more likely to do better in situations where seasonal fluctuations are the main climate influence.
The new findings represent a hypothesis on the relationship between climatic variability and species range size. This, in particular, has implications for how these animals respond to climate change. In the long term, it's likely that "thermal specialists" may not do all that well.
Currently, climate change is causing temperatures to rise. This especially affects mountainous climates, where species can only rise so high to escape the warmer temperatures before running out of habitat. The pika, which lives in the Arctic, is a good example of a species that's currently experiencing this type of habitat shift.
The findings reveal a bit more about how animals respond to temperature and, possibly, also respond to climate change. As temperatures heat up, it's important to learn which species are most at risk when it comes to a changing climate.
The findings are published in the March 2016 journal Science.
