An animal studied at Berkeley's Museum of Vertebrate Geology. It demonstrated the effect of a changing environment on a species.
A mountain species, the chipmunk has moved up as California has warmed. That is, the early Museum data showed its vertical range was between X and Y feet of elevation. And over the past century, both X and Y have increased: the chipmunk has been heading upslope as its environment changed. Moreover, scientists examining the Museum’s hundred-year-old stored specimens have identified the genetic changes that allow the chipmunk to survive in a lower density of oxygen.)
So that’s neat: sometime not too long after 1908, some person caught a chipmunk, recorded a lot of information about it – like where the chipmunk was, on a topographical map. That person also wandered over the countryside, marking where chipmunks were. Later, someone used the topographical map to calculate the range of this group of chipmunks. Then *someone* filed the information and the corpse somewhere. Perhaps a century later, old data on chipmunks was compared to recent data and, because the chipmunks were seen to have moved higher, someone was inspired to pull a chipmunk corpse out of a drawer somewhere and scrape off some DNA.