Evolution of multicellular life cycles under costly fragmentation

Area of Science:

• Evolutionary biology
• Theoretical biology
• Cellular biology

Background:

• Life cycles range from unicellular to multicellular fragmentation.
• Factors driving life cycle evolution remain incompletely understood.

Purpose of the Study:

• To investigate the impact of fragmentation costs on the evolution of life cycles.
• To model how these costs influence population growth and life cycle diversity.

Main Methods:

• Modeling a group-structured population of undifferentiated cells.
• Simulating reproduction via fragmentation with associated costs (delay, risk, cell loss).

Main Results:

• Fragmentation costs substantially increase the variety of possible life cycles.
• These costs directly correlate with the evolution of life cycles involving multiple offspring.
• Fragmentation costs alone can promote multicellularity, favoring fragmentation into single cells.

Conclusions:

• Fragmentation costs are a key driver in the evolution of diverse life cycles.
• The emergence of multicellular life cycles is strongly linked to the costs associated with splitting.
• Even when solitary individuals have an advantage, fragmentation costs can lead to collective splitting behavior.