Convergent evolution on the molecular level.

Area of Science:

• Evolutionary Biology
• Molecular Biology
• Neurobiology

Background:

• Organisms adapt to environments through evolutionary processes like divergence and convergence.
• Molecular biology techniques enable the investigation of these evolutionary processes at the molecular level.
• Molecular divergence is well-documented, but convergent molecular evolution is less reported and often debated.

Purpose of the Study:

• To discuss the different types of convergent molecular evolution.
• To outline the criteria for evaluating claims of molecular convergence.
• To present examples of claimed molecular convergence in neurobiology.

Main Methods:

• Review of existing literature on molecular evolution, divergence, and convergence.
• Analysis of criteria for establishing molecular convergence.
• Examination of specific case studies in neurobiology.

Main Results:

• Molecular divergence is common, involving changes in molecular sequences and functions over evolutionary time.
• Fewer, often controversial, examples of molecular convergence exist.
• Neurobiological examples include opsins, gap junction proteins, neurotransmitter receptors, ion channels, and venoms targeting ion channels.

Conclusions:

• Convergent molecular evolution, while less common than divergence, is a significant evolutionary process.
• Rigorous criteria are necessary to validate claims of molecular convergence.
• Neurobiology provides compelling, though sometimes debated, examples of molecular convergence.