Influence of dominance rank in the quality of horns in farmed eland

María Martínez Valdeolivas

Master's thesis

Abstract:

Social Ungulates form different kinds of group structures in the wild, which frequently change in size and composition along the year. In this thesis, the common eland was used as animal model to study the behavioural patterns among these different social groups. Social relationships in thirty-two groups of farmed elands were studied. These groups were based on three main social structures: females-based groups, males-based groups and mixed groups. In all the group structures, the most frequent social interaction observed was based on dominance displays. Nevertheless, female-based groups were less aggressive than male-based groups, while these present a strongest linearity probably linked with the access to female. Differences were found in the occurrence of certain displays: females use yield in high frequency, while males displayed wrestle more frequently. This is in agreement with the expected function according to their horn dimorphism. All the studied group structures showed to have a linear hierarchy according to Landau's index and triangle transitivity. Moreover, these behavioural differences lead to the existence differences in the strength of Landau's linearity index (although these differences were not reflected by the triangle transitivity).

Abstract:

Social Ungulates form different kinds of group structures in the wild, which frequently change in size and composition along the year. In this thesis, the common eland was used as animal model to study the behavioural patterns among these different social groups. Social relationships in thirty-two groups of farmed elands were studied. These groups were based on three main social structures: females-based groups, males-based groups and mixed groups. In all the group structures, the most frequent social interaction observed was based on dominance displays. Nevertheless, female-based groups were less aggressive than male-based groups, while these present a strongest linearity probably linked with the access to female. Differences were found in the occurrence of certain displays: females use yield in high frequency, while males displayed wrestle more frequently. This is in agreement with the expected function according to their horn dimorphism. All the studied group structures showed to have a linear hierarchy according to Landau's index and triangle transitivity. Moreover, these behavioural differences lead to the existence differences in the strength of Landau's linearity index (although these differences were not reflected by the triangle transitivity).

Keywords

Animal behavior, Taurotragus oryx, Hierarchy, Horn, Common Eland

Keywords

Animal behavior, Taurotragus oryx, hierarchy, Horn, Common Eland

Language used: English

Date on which the thesis was submitted / produced: 24. 4. 2015

Thesis defence

• Supervisor: Francisco Ceacero Herrador, Ph.D.

Czech University of Life Sciences Prague

Faculty of Tropical AgriSciences

Master programme / field:
Tropical Agriculture / Wildlife Management in the Tropics and Subtropics