S1E02 - Evolutionary "Why?"

Season 1: The Science of Aging | Episode 2: Evolutionary "Why?"

In this episode of "The Deep Dive," we tackle the profound question of why aging exists, exploring beyond the simple wear and tear narrative. We delve into the deeply embedded evolutionary reasons underlying aging, focusing on three foundational theories: Sir Peter Medawar's mutation accumulation theory, George C. Williams' antagonistic pleiotropy, and Thomas Kirkwood's disposable soma hypothesis. Our journey is designed to illuminate the evolutionary calculus allowing aging to persist and its implications on modern interventions.

We begin with a compelling natural experiment involving the Virginia opossums on Sapelo Island to set the stage for this exploration. The episode further dissects the biological mechanisms reflecting these evolutionary principles, examining key examples like the growth hormone IGF-1 signaling and the guardian of the genome, P53. The conversation extends to cutting-edge interventions - including caloric restriction and drugs like rapamycin - highlighting their attempts to manipulate these ancient trade-offs.

Listeners are invited to explore the incredible diversity within the animal kingdom, with examples from naked mole rats to bowhead whales, to understand the limits and possibilities in longevity. Finally, we confront the enduring trade-off between regeneration and cancer risk, offering a nuanced perspective on how future scientific breakthroughs might navigate these challenges. Join us for an intellectual adventure merging history, biology, and evolutionary theory to unpack the intricate logic of aging.