Since the time of Darwin, evolutionary biologists have wondered why the lifespans of different species vary so significantly. A new model now suggests that the life expectancy of any given species is a function of evolutionary pressures — a conclusion that hints at the potential for powerful anti-aging interventions in humans.
The new paper, which now appears in Physical Review Letters, challenges popular conceptions about the nature of aging and why it manifests at different rates in different organisms, including species that are closely related.
By running variations of their model hundreds of thousands of times, a research team led by Yaneer Bar-Yam from the New England Complex Systems Institute (NECSI), in collaboration with the Harvard Wyss Institute for Biologically Inspired Engineering, observed that evolution favors shorter lifespans in environments where resources are scarce and when pressures to procreate are particularly intense. The simulations appeared to show that lifespans of animals — humans included — are genetically conditioned, and not the result of gradual wear-and-tear. It's a surprising result, one that gives added credence to the burgeoning paradigm known as "programmed aging." At the same time, the study shows that current efforts to develop anti-aging interventions may be based on incorrect assumptions.