Speciation: more likely through a genetic or through a learned habitat preference?

Area of Science:

• Evolutionary biology
• Speciation research

Background:

• Sympatric speciation, the evolution of new species from a single ancestral species while inhabiting the same geographic region, is challenging to explain.
• Reproductive isolation mechanisms are crucial for understanding how new species arise without geographic separation.

Purpose of the Study:

• To model the evolution of habitat preference as a mechanism for sympatric speciation.
• To investigate the roles of genetic mechanisms and learning in the evolution of habitat preference and subsequent speciation.

Main Methods:

• Adaptive-dynamical analysis of a mathematical model.
• Individual-based simulations to explore genetic and learning-based speciation.

Main Results:

• Evolution can lead to either specialist populations with genetic habitat preferences or generalist populations.
• Generalist populations experience disruptive selection, potentially leading to speciation.
• Learning enhances disruptive selection, promoting speciation, especially with low learning costs.
• High learning costs favor genetic habitat preference evolution, contingent on mutation effects or gene linkage.

Conclusions:

• Habitat preference evolution is a viable pathway for sympatric speciation.
• Learning can accelerate speciation by increasing disruptive selection.
• The interplay between learning costs, genetic mechanisms, and selection intensity determines the mode of speciation.