Viruses and mobile elements as drivers of evolutionary transitions

Area of Science:

• Evolutionary biology
• Genetics
• Systems biology

Background:

• Life's history features major evolutionary transitions, creating new biological organization levels.
• These transitions include the origin of cells, multicellular organisms, and eusocial animals.
• Cells host diverse, autonomous selfish genetic elements like plasmids, transposons, and viruses.

Purpose of the Study:

• To present evidence that evolutionary transitions up to multicellularity are driven by host-parasite coevolution and public goods sharing.
• To explore the dual role of selfish elements in driving evolutionary transitions.

Main Methods:

• Mathematical modeling of evolutionary processes (e.g., replicator populations, unicellular organisms).
• Comparative genomic analysis of gene recruitment in cellular life forms.

Main Results:

• Mathematical models show increasing organizational complexity prevents host-parasite system collapse.
• Genomic analysis reveals recruitment of essential genes, enabling evolutionary transitions, often involves parasitic elements.
• Selfish genetic elements drive transitions at two distinct levels.

Conclusions:

• Coevolution with selfish genetic elements and public goods sharing are key drivers of major evolutionary transitions.
• Increasing biological organization is a mechanism to maintain system stability against parasitic pressure.
• Selfish elements contribute to the emergence of complexity and essential functions throughout evolutionary history.