Interspecific interactions between the little pocket mouse (Perognathus longimembris) and the dark kangaroo mouse (Microdipodops megacephalus) were tested in the laboratory. P. longimembris was statistically dominant over M. megacephalus. The dominant-subordinate relationships shown by our laboratory results indicate that interspecific aggression may be one mechanism involved in keeping these sympatric species ecologically separated.
Blaustein, Andrew R. and Risser, Arthur C. Jr.
"Dominance relationships of the dark kangaroo mouse (Microdipodops megacephalus) and the little pocket mouse (Perognathus longimembris) in captivity,"
Great Basin Naturalist: Vol. 34
, Article 11.
Available at: http://scholarsarchive.byu.edu/gbn/vol34/iss4/11