Dietary morphology of two island-endemic murid rodent clades is consistent with persistent, incumbent-imposed competitive interactions

Dakota M. Rowsey, Ryan M. Keenan, Sharon A. Jansa

Research output: Contribution to journalArticlepeer-review

8 Scopus citations


A lineage colonizing a geographic region with no competitors may exhibit rapid diversification due to greater ecological opportunity. The resultant species diversity of this primary-colonizing (incumbent) clade may limit subsequent lineages’ ability to persist unless these non-incumbent lineages are ecologically distinct. We compare the diversity in diet-related mandibular morphology of two sympatric murid rodent clades endemic to Luzon Island, Philippines—incumbent Phloeomyini and secondary-colonizing Chrotomyini—to the mandibular morphological diversity of Sahul Hydromyini, the sister clade of Chrotomyini and the incumbent murid lineage on the supercontinent of Sahul. This three-clade comparison allows us to test the hypothesis that incumbent lineages can force persistent ecological distinction of subsequent colonists at the time of colonization and throughout the subsequent history of the two sympatric clades. We find that Chrotomyini forms a subset of the diversity of their clade plus Sahul Hydromyini that minimizes overlap with Phloeomyini. We also infer that this differentiation extends to the stem ancestor of Chrotomyini and Sahul Hydromyini, consistent with a biotic filter imposed by Phloeomyini. Our work illustrates that incumbency has the potential to have a profound influence on the ecomorphological diversity of colonizing lineages at the island scale even when the traits in question are evolving at similar rates among independently colonizing clades.

Original languageEnglish (US)
Article number20192746
JournalProceedings of the Royal Society B: Biological Sciences
Issue number1921
StatePublished - Feb 26 2020

Bibliographical note

Publisher Copyright:
© 2020 The Author(s) Published by the Royal Society. All rights reserved.


  • Community assembly
  • Geometric morphometrics
  • Incumbency effects
  • Macroevolution
  • Oceanic island
  • Systematics


Dive into the research topics of 'Dietary morphology of two island-endemic murid rodent clades is consistent with persistent, incumbent-imposed competitive interactions'. Together they form a unique fingerprint.

Cite this