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| Chironomus plumosus , a midge. Photo courtesy of http://www.entomart.be/ |
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| Above, a semi-transparent head capsule from a midge that prefers cooler water temperatures. Head capsules encase a midge's head until it reaches adulthood. Researchers use specific characteristics of head capsules, such as teeth, to differentiate between midges from different taxonomic groups. This midge belongs to the taxonomic group Sergentia. Photo courtesy of David Porinchu. |
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At left, a head capsule belonging to a midge of the Dicrotendipes group. Midges in this group prefer slightly warmer water temperatures. Researchers use certain characteristics of head capsules, including teeth, to differentiate between different types of midges. Photo courtesy of David Porinchu. |
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| Jeff Munroe, a study co-author and an assistant professor of geology at Middlebury College in Vermont, holds a sediment core. This small column of lake-bottom sediment holds a wealth of climatological information. Photo courtesy of David Porinchu. |
