Character displacement in Pleistocene kangaroos
thesisposted on 2022-03-29, 02:44 authored by Hayley Bell
Palaeontological studies are helpful not only for understanding how communitiesinteracted in the past, but also for testing ecological models in deep time. Macropods have a rich fossil record and there are many living species, making them optimal for palaeoecological studies. Character displacement between closely related coexisting species is a developing ecological topic and testing for it in evolutionary time can enhance our understanding of the processes lying behind it. Using length and width measurements of dentary molars I looked for the presence of displacement in modern and Pleistocene communities of kangaroos using Willams’ V-test. Results indicated that there was little to no character displacement and so the hypothesis that this phenomenon enabled kangaroos to coexist was rejected. The Kruskal-Wallis test showed some significant variation for modern and extinct kangaroos but not enough to support displacement. This conclusion brings forward more questions about kangaroo palaeoecology: how do these species coexist? Was competition not as strong as we thought? Did coexisting Pleistocene kangaroos use resource partitioning like modern species do? Further studies of kangaroo ecology, both in modern communities and Pleistocene, will yield greater insights into how species interact with eachother and how their evolutionary history has been shaped.