Date: September 24, 2016
Source: University of Washington
Biologists of all stripes attest to evolution, but have debated its details since Darwin's day. Since changes arise and take hold slowly over many generations, it is daunting to track this process in real time for long-lived creatures.
"We know that evolution occurs -- that species change," said Dee Boersma, a University of Washington professor of biology. "But to see this process in long-lived animals you have to look at generations of individuals, track how traits are inherited and detect selection at work."
Boersma studies one particularly intriguing long-lived species, the Magellanic penguins of South America. She has spent 34 years gathering information about their lifespan, reproduction and behavior at Punta Tombo, a stretch of Argentine coast that serves as their largest breeding site. Boersma and her colleagues combed through 28 years' worth of penguin data to search for signs that natural selection -- one of the main drivers of evolution -- may be acting on certain penguin traits. As they report in a paper published Sept. 21 in The Auk: Ornithological Advances, selection is indeed at work at Punta Tombo.
"This is the first decades-long study to measure selection in penguins, and only the second one for birds overall," said lead author Laura Koehn, a graduate student in the UW School of Aquatic and Fishery Sciences who worked with Boersma as an undergraduate.