Biological Lifespan of Humans and the Influence of Growth Parameters and Temperature

Completed at the Research Science Institute (RSI) summer program under Prof. James Michaelson of Harvard Medical School. There's currently no mathematical model for projecting an organism's lifespan or how temperature variation affects it. Historically it's taken thousands of years for a meaningful shift in human lifespan, a change attributed to Life History Theory (LHT) — the trade-offs an organism makes to maintain maximum fitness across generations. Before the 18th century, and outside the influence of modern medicine, temperature and climatic variation were the primary drivers of lifespan change, since they affected habitat conditions, internal metabolic rate, and growth itself.

Lifespan is dependent on specific growth parameters and can be modeled with the lifespan equation, so this research analyzes how varying those parameters — and temperature specifically — affects lifespan, and projects how it could change going forward. It uses the Mitotic Fraction (the fraction of dividing cells in an organism) and the lifespan equation, both part of the Binary Cellular Biology framework, to study temperature's influence on lifespan and predict future lifespan under modern-day climate change.