# Is Photosynthetic Capacity Associated With Diversification of C3 Plants?

## TL;DR

This paper challenges a previous claim that higher photosynthetic capacity in C3 plants leads to more species diversification.

## Contribution

The study shows that previous conclusions about photosynthetic capacity and diversification were based on flawed methods.

## Key findings

- Reanalysis found no link between photosynthetic capacity and diversification rates in C3 plant genera.
- Previous methods used unreliable assumptions about diversification and ancestral traits.
- Model-based phylogenetic comparative methods provided more accurate results.

## Abstract

Schweiger and Schweiger (2024) recently proposed that the evolution of greater photosynthetic capacity in C3 plant species may be linked to increased species diversification. This conclusion is premature because their methods cannot reliably estimate diversification rates or ancestral trait values. Reanalyzing the data set using model‐based phylogenetic comparative methods reveals no evidence that photosynthetic capacity is associated with diversification rates among C3 plant genera.

Schweiger and Schweiger (2024) linked photosynthetic capacity to diversification rate in C3 vascular plants. However, the diversification rate estimates were not conditioned on extinction or incomplete sampling, and the ancestral trait reconstruction was based on unrealistic assumptions that are highly sensitive to incomplete sampling. Reanalysis using model‐based phylogenetic comparative methods (PCMs) in this paper finds no association between photosynthetic capacity and diversification rate among vascular plant genera.