Microevolutionary processes impact macroevolutionary patterns

Jingchun Li,L Lacey Knowles,Jeet Sukumaran,Jen-Pen Huang

doi:10.1186/s12862-018-1236-8

Abstract

BackgroundMacroevolutionary modeling of species diversification plays important roles in inferring large-scale biodiversity patterns. It allows estimation of speciation and extinction rates and statistically testing their relationships with different ecological factors. However, macroevolutionary patterns are ultimately generated by microevolutionary processes acting at population levels, especially when speciation and extinction are considered protracted instead of point events. Neglecting the connection between micro- and macroevolution may hinder our ability to fully understand the underlying mechanisms that drive the observed patterns.ResultsIn this simulation study, we used the protracted speciation framework to demonstrate that distinct microevolutionary scenarios can generate very similar biodiversity patterns (e.g., latitudinal diversity gradient). We also showed that current macroevolutionary models may not be able to distinguish these different scenarios.ConclusionsGiven the compounded nature of speciation and extinction rates, one needs to be cautious when inferring causal relationships between ecological factors and macroevolutioanry rates. Future studies that incorporate microevolutionary processes into current modeling approaches are in need.

Highlights

Macroevolutionary modeling of species diversification plays important roles in inferring large-scale biodiversity patterns
We demonstrate that population level dynamics can impact macroevolutionary patterns, and that current macroevolutionary models may not discriminate among processes, resulting in difficulties discerning underlying causes of the formation of biodiversity patterns
Latitudinal diversity gradient in birds The simulation results show that microevolution level processes can result in a higher speciation rate in the temperate regions while maintaining the high species richness in the tropics, and stress that different sets of microevolutionary parameters can generate similar gradient patterns (Fig. 2)

Summary

Introduction

Macroevolutionary modeling of species diversification plays important roles in inferring large-scale biodiversity patterns. Numerous studies [3,4,5,6] have shown that species diversity can be influenced by both extrinsic (e.g., energy supply, environmental stability, climate) and intrinsic (e.g., dispersal ability, adaptive traits) factors These factors inform the lineage diversification process through a combination of speciation and extinction events. Extinction, or rate shifts are estimated to maximize the likelihood of a given phylogeny [19] These rates can be compared among clades, or used to statistically test if observed diversity patterns are associated with biological traits, geographical events, or other environmental factors [13, 18, 20,21,22,23]

Methods

Results

Conclusion