Larger Doesn't Mean Longer: Neither Body Size Nor Seed Size Affect the Gut Retention Times of Aldabra Giant Tortoises

Neither the body size of Aldabra giant tortoises nor the size of ingested seeds influences their gut retention times, challenging assumptions about seed dispersal dynamics. Researchers fed tortoises of varying sizes (ranging from 0.6 to 104 kg) with artificial seeds of different diameters (2, 4.5, and 10 mm). Despite expectations that larger dispersers or seeds would result in longer retention times, all beads were defecated within a consistent timeframe, averaging 14.6 ± 3.7 days post-ingestion. This finding has significant implications for understanding seed dispersal effectiveness and for rewilding projects involving Aldabra giant tortoises as proxies for extinct megafauna on other oceanic islands.

Falcón, W., Bunbury, N., & Hansen, D. M. (2021). Larger Doesn’t Mean Longer: Neither Body Size Nor Seed Size Affect the Gut Retention Times of Aldabra Giant Tortoises. Herpetologica, 77(2). https://doi.org/10.1655/herpetologica-d-21-00060