Trunk Tip Wear in Wild African Savanna Elephants

The anatomy and function of tactile structures, such as vibrissae, are typically studied in captive animals, but we know little about how tactile structures compare between captive and wild animals. We analyzed trunk tip morphology in wild (n = 6) and captive (n = 6) adult African savanna elephants (Loxodonta africana). We found striking differences in both vibrissae and skin structure between the two groups. Wild elephants showed significant vibrissae abrasion, with frontal trunk tip vibrissae often entirely worn down, whereas captive elephants retained proportionally more long vibrissae, particularly along the trunk tip rim. In wild elephants, vibrissae rarely exceeded 1 cm in length, whereas many captive individuals had vibrissae several centimeters long. In contrast, vibrissae inside the nostril-a trunk region not directly exposed to feeding-were similar in length and density between wild and captive elephants. Additionally, trunk tip skin in wild elephants appeared to be worn down to a smooth surface, whereas all captive elephants showed distinct papillary skin structure and folds at the lateral trunk tip opening and nasal septum. These findings suggest that wild elephants experience feeding-related trunk abrasion, leading to significant alterations in both vibrissa structure and skin texture. Our results highlight the importance of studying sensory structures in wild animals to understand sensing in natural environments.