Mathematicians map the geometry of parasites evolving inside hosts

A research team developed a geometric framework for modeling nested evolutionary trees, where one organism's evolution is embedded inside another's (like parasites inside hosts). This makes it possible to do precise mathematical operations on these co-evolutionary systems that weren't possible before.

For decades, biologists could describe co-evolutionary systems (host-parasite, plant-pollinator) only qualitatively or through simulation. This paper gives the system a formal geometric structure, which means researchers can now apply tools from mathematics to ask quantitative questions about these relationships. The practical payoff is years away, but this is the kind of foundational math that eventually lets biology become more predictive rather than purely descriptive.