Comparative Population Genomics of Native (Sundamys Muelleri) and Invasive (Rattus Rattus) Rodents Along an Urbanization Gradient in Borneo

Giselle Agatha Herrera, Fordham University


Urbanization continues to be one of the most significant processes of global change modifying the environment rapidly and permanently. With increases in infrastructure and human settlement, natural areas become fragmented, and small populations in these patches become more vulnerable to genetic drift and are unable to disperse due to barriers to gene flow. Often these pervasive alterations to the environment result in the introduction of exotic species that can thrive in urban habitats with anthropogenically made available resources. Both native and nonnative wildlife that inhabit cities and nearby non-urban areas serve as ideal models to show how populations are evolving in response to developmental pressures. While native rodents in urban areas exhibit patterns of low genetic diversity and genetic connectivity, populations of invasive rodents reveal high connectivity and gene flow. Studying the evolutionary implications of this ecological change, particularly in understudied regions of rapid development like in biodiverse rich areas of Southeast Asia, will be vital to understand the variation of species responses to urbanization. In this study, I explored genetic diversity, structure, and connectivity of populations of the native Müller's giant Sunda rat (Sundamys muelleri) and invasive black rat (Rattus rattus) across an urbanization gradient on the island on Borneo. Sundamys muelleri exhibited decreased genetic diversity in urban areas and was differentiated from rural and suburban locations. Populations of S. muelleri also displayed low genetic connectivity with urbanization posing a potential barrier to gene flow. Rattus rattus exhibited decreased genetic diversity in rural areas and a clinal genetic structure across the urbanization gradient. Populations of R. rattus also displayed high genetic connectivity, but development likely still prevents dispersal opportunities. This research provides useful information on how urbanization evolutionarily affects these two species of rodents (a native and invasive) and how development impacts population structure and connectivity. This information will provide useful for the conservation of endemic species in Borneo, to better understand the population genetics of these vector species and inform pest management across the urbanization gradient.

Subject Area

Ecology|Evolution and Development

Recommended Citation

Herrera, Giselle Agatha, "Comparative Population Genomics of Native (Sundamys Muelleri) and Invasive (Rattus Rattus) Rodents Along an Urbanization Gradient in Borneo" (2020). ETD Collection for Fordham University. AAI27957089.