Living in Extremes – An Outlook on Human Adaptivity Living in Extremes – An Outlook on Human Adaptivity

Cara Ocobock, PhD

Despite her debut in the field of Cellular, Molecular, and Developmental Biology in the University of Michigan, Dr. Ocobock, Director of the Human Energetics Laboratory at the University of Notre Dame, Indiana, has since shifted her focus towards Life on a more macroscopic scale – and particularly, towards the human species.

Combining her background in Anthropology with her enthusiasm for powerlifting and outdoor sports [1], Ocobock has taken part in numerous studies exploring the physiological and behavioral mechanisms underlying biological adaptation to extreme climates and how these factors could affect physical activity. One of her current projects with collaborators at the University of Missouri and the University of North Texas seeks to gauge the physiological correlation between cold adaptations’ specific anatomical indicators and the advantages extinct cold- climate populations such as the Neanderthals may have had in comparison to modern humans [1].

Ocobock’s love for Humanity goes far beyond organic matter, biochemical reactions, and Darwinian evolution. Through her work, she has encountered many different people across the world, from runners in a cross-country race to reindeer herders in Northern Finland [2]. The latter are currently the protagonists of Ocobock’s work in collaboration with researchers from the University of Lapland and University of Oulu.

Reindeer herders in the Arctic Circle are a highly active population inhabiting extreme environments subject to a cold, rigorous climate. By studying their life ways, habits, and traditions through a multidisciplinary lens, Ocobock and her research team expect to gain anthropological and biological context regarding how these cold climate populations evolved to adapt to their harsh surroundings.

Chief among these adaptations could be the very expansion of the average lifespan in such individuals. Although reindeer commerce management has been linked to an increased risk of fatal occupational accidents [3], intrinsic factors related to health indicators in these populations have consistently shown a promising outlook on human health improvement.

One such factor is the prevalence of brown adipose tissue (BAT) in the body composition of reindeer herders. This uniquely mammalian tissue is particularly relevant for neonatal body temperature maintenance, favoring heat production by combusting triglycerides in mitochondria-rich brown adipocytes. This process occurs due to the presence of uncoupling protein 1 (UCP-1) in the inner mitochondrial membrane, which transports hydrogen ions across the membrane to dissipate the proton gradient generated during organic substrate oxidation [4].