# Fisher Information and the Dynamics of Multicellular Ageing

## TL;DR

This paper uses Fisher information from information theory to model how multicellular organisms age through the balance of cell competition and cooperation.

## Contribution

A novel theoretical model of multicellular ageing using Fisher information to explain dynamics of cell competition and cooperation.

## Key findings

- Fisher information parametrizes the tension between cell reproduction and multicellular homeostasis through non-monotonic dynamics.
- Optimal ageing dynamics depend on a balance of competition and cooperation among cells.
- Fisher information suggests biological age inference evolves through complex dynamics over an organism's lifespan.

## Abstract

Information theory has long been integrated into the study of biological ageing, for example, in examining the roles of genetic and epigenetic fidelity in cellular and organismal longevity. Here, we introduce a theoretical model that interprets ageing in multicellular systems through the lens of Fisher information. Previous theories have suggested that the ageing of multicellular organisms is an inevitable consequence of the inherent tension between individual cell reproduction and the homeostasis of the multicellular system. Utilising concepts from information theory and statistical mechanics, we show that Fisher information parametrises the dynamics of this tension through non-monotonic behaviour, which depends on an optimal balance of competition and cooperation between cells. Moreover, Fisher information suggests that the ability to infer true biological age from a sample evolves through complex dynamics over an organism’s lifespan.