Biology ETDs

Publication Date



Despite being the most studied species on the planet, ecologists typically do not study humans the same way we study other organisms. My Ph.D. thesis contributes to scientific development in two ways: i) synthesizing our understand of the inter and intraspecific variation in social behavior in an understudied rodent lineage, the caviomorphs, providing a comparative context to understand social evolution in general, and 2) developing a macroecological approach to understand the metabolic trajectory of the human species. Through comparative analysis, chapter 2 synthesizes the available information on the diversity of sociality in the caviomorph rodents, both within and across species. Studies and theory derived from better-studied mammalian taxa establish an integrative and comparative framework from which to examine social systems in caviomorphs. We synthesize the literature to evaluate variation in space use, group size, mating systems, and parental care strategies in caviomorphs in the context of current hypotheses. We highlight unique aspects of caviomorph biology and offer potentially fruitful lines for future research both at the inter and intraspecific levels. We can gain unique insights into the ecological drivers and evolutionary significance of diverse animal societies by studying this diverse taxon. Chapter 3 outlines core ecological principles that should be integral to a science of sustainability: 1) physical conservation laws govern the flows of energy and materials between human systems and the environment, 2) smaller systems are connected by these flows to larger systems in which they are embedded, 3) global constraints ultimately limit flows at smaller scales. Over the past few decades, decreasing per-capita rates of consumption of petroleum, phosphate, agricultural land, fresh water, fish, and wood indicate that the growing human population has surpassed the capacity of the Earth to supply enough of these essential resources to sustain even the current population and level of socioeconomic development. Chapter 4 applies a socio-metabolic perspective of the urban transition coupled with empirical examination of cross-country data spanning decades. It highlights the central role of extra-metabolic energy in global urbanization and the coinciding transition from resource extraction to industrial and service economies. The global urban transition from resource producers in rural areas, to industrial and service employment in urban systems is fuelled by supplementing extra-metabolic energy in the form of fossil fuels for decreasing human and animal labor. Collectively, I hope this work demonstrates the utility of comparative analysis and synthesis in understanding the evolutionary ecology of sociality and the power of a macroecological approach in understanding the metabolic ecology and trajectory of the human species.




Human Ecology, Macroecology, Metabolic Ecology, Sociality, Sustainability, Cities

Document Type


Degree Name


Level of Degree


Department Name

UNM Biology Department

First Advisor

Brown, James

First Committee Member (Chair)

Smith, Felisa

Second Committee Member

Moses, Melanie

Third Committee Member

Milne, Bruce