A single small bag of snails collected in a one meter by one meter section of lake floor contained dozens of specimens and eight different species. (Photo courtesy Center for Limnology)
Field season is, of course, where the best photo ops and a lot of the fun of being a research scientist happens.
Then there's the arduous task of combing through specimens, which is how professor Peter McIntyre in the University of Wisconsin-Madison's Center for Limnology and Ellen Hamann, the manager of the McIntyre lab, have spent this winter.
Last summer, the McIntyre lab worked in Lake Tanganyika on the coast of Tanzania to examine an ecosystem that thrives in spite of limited nutrients.
The collection of snail specimens McIntyre and Hamann brought back from Tanzania was so massive that, earlier this winter, they called in outside help in the form of two world-renowned experts from the zoology department of London’s Natural History Museum. Elllinor Michel and Jon Todd flew in to help identify the nearly 12,000 snails Ellen and Pete pulled up from the bottom of Lake Tanganyika outside of both the port town of Kigoma and the forested shores of Mahale Mountains National Park, which the team first visited last summer.
McIntyre began working on Lake Tanganyika as an undergraduate student, when Michel served as his mentor.
McIntyre
“Because of the training I’ve had from her in the past,” he says, “we did okay on taxonomy of the snails from the area [around Kigoma] where we worked for the past 14 years. But we were pretty clueless about anything we got from this new region. So we’re just making the first baby steps to figuring out what’s [near Mahale] and it only took, what, 10 or 15 years to figure out what was down in the other area?”
Michel says Tanganyika is one of the most ancient extant lakes in the world, estimated at 15 million years old. “That’s the amount of time that it’s been working on being a lake,” she clarifies, “it started out as a swampy area, but it’s probably been in place as a super deep isolated body of freshwater for a good 6 million years and potentially longer than that.”
For perspective, that’s 1,000 times longer than the Great Lakes have been around. And that means aquatic organisms in Lake Tanganyika have been adapting and evolving for a long, long time. The result is a daunting collection of specimens representing a staggering diversity of species.
Now some of that diversity is in Hasler Lab, being sorted by genus and species, and giving the researchers a better idea of the community composition of snails in Lake Tanganyika. More important, these snails will help the team understand how that composition is affected by habitat. Comparing what snails thrive in the heavily sedimented waters off of the developed shoreline near Kigoma to the several dozen species of snails that call the more “pristine” waters around Mahale Mountains National Park home, the McIntyre lab will be able to generate some hard data on how Africa’s great lake is faring in its 15 millionth year of existence.
And, should any of this research wind up in the pages of a scientific journal, thanks to Michel and Todd, everyone can rest assured that, as Michel says, “we’re all talking about the same thing.”
Story from the Center for Limnology blog. Check out the blog for more limnology stories.