Darwin Today @ NMNH
Meet Dr. Gene Hunt
Gene Hunt, PhD, is curator of Ostracoda, which are crustaceans like shrimp and crabs, but tinier—only about 1 mm (1/25 in.) long.
I find it gratifying that an insight made more than 150 years ago can still contribute to understanding living things today.
Like Charles Darwin, I sometimes spend a lot of time thinking about natural selection. Most often, that’s because I observe fossil evidence of change over time, and considering natural selection can help make sense of these patterns.
I was puzzled that one group of ostracodes evolved larger bodies over millions of years until I remembered that natural selection often favors larger bodies in colder climates. The ostracodes lived more than 1 km (3,300 ft) deep in the ocean, which has grown colder over millions of years, by about 10oC (18oF). I hypothesized that ostracodes had evolved larger sizes as an adaptation to increasingly cold temperatures.
Colleagues and I tested this idea, and we found that ostracodes grew larger when the ocean cooled but not when ocean temperatures stayed the same.
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