A new paper by researchers at George Mason University and the University of Otago in New Zealand shows a strong link between the diversity of organisms at the bottom of the food chain and the diversity of mammals at the top.
Mason geologist Mark D. Uhen  says that throughout the past 30 million years, changes in the diversity of whale species living at any given time correlates with the evolution and diversification of diatoms, tiny, abundant algae that live in the ocean. In the paper “Climate, Critters, and Cetaceans: Cenozoic Drivers of the Evolution of Modern Whales,” which was published in the February 19, 2010, issue of Science, Uhen and co-author Felix G. Mark of Otago show that the more kinds of diatoms living in a time, the more kinds of whales there are.
“This study shows that if we look at the bottom of the food chain, it might tell you something about the top,” says Uhen. “Diatoms are key primary producers in the modern ocean and thus help form the base of the marine food chain. The fossil record clearly shows that diatoms and whales rose and fell in diversity together during the past 30 million years.”
Uhen says this is the first time that such a correlation has been shown. The researchers hope these findings will encourage other specialists to look at other animals with a similar narrow ecology to see if this link translates.
In the future, he hopes to conduct research on how whales became the largest living organisms in the world.
—Tara Laskowski, MFA ’05