| A variety of pathologies have been noted on Mammut americanum (American mastodon), including subchondral articular surface undermining on metapodials (documented in extinct bison). Metapodial undermining in mastodons has been ascribed to tuberculosis (Mycobacterium tuberculosis), but this diagnosis has not been tested by comparisons with Recent material. The following questions are here addressed by comparisons with Recent proboscideans: (1) To what degree do Recent elephants show undermining? (2) Does undermining vary based on species, age, sex, or whether the animal is wild or captive? (3) Does undermining preferentially affect a specific metapodial? and (4) Can this undermining be firmly linked to tuberculosis in Recent elephants, and be used to interpret the presence of the disease in the American mastodon?; To answer these questions, 165 metapodials from 17 skeletal specimens of Recent elephants were examined for the presence of undermining. Of the 165 metapodials studied, 103 (62%) had undermining. The third metapodial most often had undermining (31 of 35; 89%). Undermining differentially affected adult elephants; no juvenile elephants in the study had undermining. Because undermining in Recent elephants affected only adults, and was most often present on the central metapodials, it is likely the result of pressure on the feet from the weight of the animal, and a normal part of Recent proboscidean skeletal anatomy, rather than the result of an infection. |
