Decoding the Dance Between Pathogens and Aging
A groundbreaking study exploring how the diversity of aging in a host population shapes the evolution of pathogens has been recognized with the 2008 American Society of Naturalists (ASN) Presidential Award.
This research provides a crucial piece of the puzzle in understanding the relentless arms race between infectious diseases and their hosts.
Explores how variation in host aging affects pathogen evolution through sophisticated modeling.
Awarded the 2008 ASN Presidential Award for the best paper published in The American Naturalist.
Reveals how demographic structure actively drives infectious disease dynamics.
The 2008 ASN Presidential Award was given to the authors of the best paper published in The American Naturalist in the previous calendar year. The winning paper was "Pathogen Dynamics Across the Diversity of Aging" by Jessica Clark, Luke McNally, and Tom Little 1 .
This research tackles a fundamental question in evolutionary biology: how does the variation in how hosts age and die affect the evolution of the pathogens that infect them? The study used sophisticated mathematical modeling to demonstrate that the diversity of aging in a host population is a powerful driver of pathogen evolution 1 .
The researchers built theoretical models to simulate how pathogens adapt to host populations with different aging patterns.
The models created virtual host populations with different "senescence profiles"—some aged rapidly, some aged slowly, and the populations had mixtures of these types.
Into these populations, virtual pathogens were introduced. These pathogens had traits, like virulence (harm to the host) and transmission rate, that could evolve over generations.
The key was to observe how pathogen traits evolved in response to the different host environments. Would they become more aggressive in a population of frail hosts? Or would they evolve to be milder in a mixed population?
Visualization of key parameters in the mathematical model used to simulate host-pathogen interactions.
The core finding was that pathogen evolution is profoundly different in a host population where individuals age at different rates compared to one where everyone ages uniformly. In a diverse population, a pathogen faces a complex trade-off. It can't optimize its strategy for just one type of host; it must find a way to survive and spread across both robust and frail individuals.
This research provides a novel framework for understanding infectious disease dynamics in real-world populations, including humans. It suggests that the demographic structure of a population is not just a backdrop for disease spread but an active driver of how dangerous those diseases can become.
The ASN Presidential Award is given annually for the best paper published in The American Naturalist, the flagship journal of the ASN. The award includes an honorarium and is selected by the Society's President, representing the pinnacle of research that aligns with the ASN's mission to advance and unify the biological sciences 1 .
In 2008, the society also recognized other eminent scientists for their lifelong contributions. While the Presidential Award honors a specific, exemplary paper, other awards celebrate sustained career achievement.
| Award | Recipient(s) | Recognition For |
|---|---|---|
| ASN Presidential Award | Jessica Clark, Luke McNally, & Tom Little | Best paper: "Pathogen Dynamics Across the Diversity of Aging" 1 |
| Honorary Lifetime Membership | Awarded to scientists whose careers epitomize the Society's mission | Conceptual unification in biology 1 |
| ASN Award for Distinguished Achievement | Honors a senior, active investigator | Making fundamental contributions to unifying biological sciences; known then as the Sewall Wright Award 1 |
| ASN Distinguished Naturalist Award | Recognizes a mid-career investigator | Significant contributions to the knowledge of an ecosystem or group of organisms; known then as the E. O. Wilson Naturalist Award 1 |
To fully appreciate this award-winning research, it helps to understand a few key concepts that form the toolkit for scientists in this field.
The reciprocal evolutionary change between a host and its pathogen. Each adapts to the other in a continuous arms race.
A fundamental theory stating that a pathogen's harm to its host (virulence) is often a consequence of its efforts to spread to new hosts (transmission).
The biological term for the process of aging, characterized by a gradual decline in function and increased mortality risk with age.
Using equations and computer simulations to represent complex biological systems and test hypotheses that are difficult to study in real time.
The 2008 ASN Presidential Award for the work of Clark, McNally, and Little exemplifies the society's core mission: to foster the conceptual unification of the biological sciences 1 . By applying evolutionary theory to the demographic process of aging, this research bridges fields that are often separate, showing how ecology, evolution, and demography are inextricably linked.
It reminds us that the fight against infectious diseases is not just a medical challenge but an evolutionary one. Understanding the rules of this ancient dance between host and pathogen is crucial for predicting and managing the plagues of both today and tomorrow.