University of Florida graduate student Kelly Speer discusses her research using DNA differences to learn about bat populations in the Caribbean, and how climate and sea level changes affect population dispersal and movements.
Assessing the movement of bats will also inform us about the movements of other animals because if bats have a difficulty with a barrier, than less-mobile animals will have a harder time with it. They are also indicators of the affects of climate in an area because they are susceptible to minor changes quickly.
Interview and videos produced by Nicolus Hartley for Explore Research at the University of Florida.
Transcript
Kelly Speer: I studied the dispersal of bats in the Bahamas. Bats are a really good model for looking at movement because they’re such good dispersers. If bats experience difficulty crossing a barrier than likely other less mobile organisms will share that difficulty. In order to assess the movements of bats in the Bahamas I measured the differences between DNA of populations that are geographically separated.
I studied the dispersal of bats in the Bahamas. Bats are a really good model for looking at movement because they’re such good dispersers. If bats experience difficulty crossing a barrier than likely other less mobile organisms will share that difficulty. In order to assess the movements of bats in the Bahamas I measured the differences between DNA of populations that are geographically separated.
So bats interact through dispersal, but in situations where there’s very little dispersal and interaction DNA accumulates changes over time and populations become distinct from each other. It’s important to look at the dispersal that’s happened over time because this tells us how climate change has played a role in affecting bat populations that are currently in the Caribbean, and if we can better understand how environmental changes have affected populations in the past we can predict how future environmental change might affect populations in the future.
So over the past two million years the climate has fluctuated between really warm periods and really cold periods and during these really cold periods ocean water is trapped in glaciers as it gets frozen. During warm periods these glaciers melt and release water into the ocean. So as water gets frozen from the ocean this decreases the sea level and as water melts from the glaciers this increases sea level and this change in sea level likely had a really big impact on low elevation places like the Caribbean islands because it only takes a change of a few meters to really make a difference in the area of exposed land and how close islands are to each other.
So this distance between islands, and between islands and the mainland, affects dispersal of populations and therefore their interaction. Based on how patterns of movement have changed over time or have remained constant through time we can identify factors that will influence dispersal of populations, bats and other animals and plants in the Caribbean as well, and correlate them to how future changes in the climate or environment or habitat resources might impact these populations.
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