MSU to Lead $1.84 mil. Biodiversity Research Project
MSU integrative biologist Janette Boughman is the lead principal investigator of a five-year, $1.84 million National Science Foundation Dimensions of Biodiversity collaborative grant to pursue novel research studying the evolution of threespine stickleback throughout Iceland.
Iceland’s glaciers have scoured the land and created lakes and rivers over many millennia. The age of these lakes ranges from a couple of hundred to thousands of years old. A fascinating ecological feature is that some lakes are fed by springs and exceptionally clear, whereas others are fed by glaciers and cloudy. Originally a marine fish—the threespine stickleback—has adapted over time to inhabit and thrive in hundreds of Iceland’s freshwater lakes.
Boughman, associate professor in MSU’s Department of Integrative Biology in the College of Natural Science, recognized this intriguing set of circumstances as a unique window from which to study adaptation, contrasting populations that were recently introduced into spring-fed versus glacial lakes with populations that have been established for many thousands of years.
Animals find prey, avoid predators and interact with social partners using sensory information such as sight, smell, taste, sound and touch. Sticklebacks rely heavily on sight. Yet Icelandic stickleback populations live in both clear and cloudy lakes – they can see easily in clear spring fed lakes but not in cloudy glacial lakes.
“This begs the question, how do their sensory systems evolve to respond to their visual environment?” Boughman said. “Do sticklebacks evolve better vision in the cloudy glacial lakes where visual information is obscured? Or instead, do other sensory systems such as smell compensate for reduced visibility in glacial lakes? What factors allow such adaptation?”
Boughman and her research team—Gideon Bradburd and Jason Keagy, MSU Department of Integrative Biology; Deborah Stenkamp, University of Idaho; and Hans Hofmann, University of Texas at Austin—will investigate the different sensory systems of Icelandic sticklebacks and then use the data collected to understand whether the way that genes are organized in the genome helps or hinders the process of adaptation.
Boughman considers Iceland an evolutionary powerhouse. Sticklebacks from the ocean migrated to Iceland’s lakes and rivers many times since the last ice age. Some lakes were colonized by stickleback 10,000 years ago while other lakes were colonized as recently as the past 100 years.
“By comparing the newer and older populations it is possible to see how much adaptation there has been for brief and long periods of time; in other words, we can estimate rates of evolution,” Boughman said. “These evolutionary rates can help answer the question about how quickly adaptation occurs in sensory systems. Finding sensory adaptation in the very young lakes would reveal that it can happen very quickly, but finding it only in the older lakes tells us that sensory adaptation takes a longer time.
Boughman added that not only do Icelandic stickleback provide a fantastic opportunity to investigate evolutionary change in sensory systems and evolutionary rate, but they can also help answer critical questions about how these evolutionary processes facilitate survival and persistence of species in rapidly changing Artic environments.
Like much of the Artic, Iceland is experiencing unprecedented climatic and ecological change.
“The Arctic environment is changing and changing very fast,” Boughman said. “Many plants and animals can’t keep up with this rapid environmental change. Against this backdrop, only the few species capable of quick adaptation are likely to persist. As people think about global climate change, they realize that some species may not adapt fast enough to keep up. This project gives us a way to understand that process.”
– College of Natural Science website