FEWER THAN 200 YEARS AGO
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the grasshoppers are very sensitive to the presence and proximity of others of their kind. When things start to get a bit too cozy, the insects switch from intolerance to attraction, forming so-called bands of nymphs. The locusts take on the appearance of the swarming insect and fly off in search of more space and food. Settlers in the native range of the locust also killed huge numbers of beavers and widened streambeds, both of which led to increased flooding and the death of locust eggs and young in the ground. These settlers also planted alfalfa over huge swathes of ground, a plant that the locust was not fond of eating. It has also been suggested that bird species from the eastern United States followed the settlers along corridors of cottonwood, preying on huge numbers of insects, including the locust. Female Rocky Mountain locusts used a pair of tough valves at end of their abdomens to excavate a tunnel and deposit their eggs below the surface of the soil, where they would be out of the sight of most predators. For added protection, the eggs were cocooned in a hardened foam egg sac with the appearance of a stale marshmallow. Some of the glaciers of the Rocky Mountains are known as grasshopper glaciers as large numbers of Rocky Mountain locusts from the swarms were driven by winds high up into the mountains, where they perished on the glaciers, only to be covered by subsequent layers of snow and ice. As these glaciers thaw, they reveal the mummified remains of these insects. Although the Rocky Mountain locust was very numerous, surprisingly few specimens are to be found in collections. Entomologists at the time saw little point in collecting such numerous animals, as it was inconceivable to them that an insect forming such vast swarms could ever become extinct.
Further Reading: Chapco, W., and G. Litzenberger. “A DNA Investigation into the Mysterious Disappearance of the Rocky Mountain Grasshopper, Mega-Pest of the 1800s.” Molecular Phylogenetics and Evolution 30 (2004): 810–14; Samways, M. J., and J. A. Lockwood. “Orthoptera Conservation: Pests and Paradoxes.” Journal of Insect Conservation 2 (1998): 143–49; Lockwood, J. A., and L. D. DeBrey. “A Solution for the Sudden and Unexplained Extinction of the Rocky Mountain Grasshopper (Orthoptera: Acrididae).” Environmental Entomology 19 (1990): 1194–1205; Lockwood, J. A. “Voices from the Past: What We Can Learn from the Rocky Mountain Locust.” American Entomologist 47 (2001): 208–15; Lockwood, J. A. Locust: The Devastating Rise and Mysterious Disappearance of the Insect That Shaped the American Frontier. New York: Basic Books, 2004.
PIG-FOOTED BANDICOOT Scientific name: Chaeropus ecaudatus Scientific classification: Phylum: Chordata Class: Mammalia Order: Peramelemorphia Family: Chaeropodidae When did it become extinct? The last verifiable specimen was collected in 1901, but it probably survived in remote areas for far longer, possibly until the 1950s. Where did it live? This marsupial was known only from the plains of inland Australia.
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