Evolutionarily stable sexual allocation by both stressed and unstressed potentially simultaneous hermaphrodites...

Area of Science:

• Evolutionary biology
• Reproductive strategies
• Sex allocation theory

Background:

• Simultaneous hermaphrodites function as both male and female.
• Resource allocation strategies are crucial for hermaphrodites, especially under environmental stress.
• Understanding sex allocation in response to stress is vital for evolutionary biology.

Purpose of the Study:

• To model how environmental stress affects resource allocation in simultaneous hermaphrodites.
• To investigate the impact of stress on the trade-off between male and female reproductive costs.
• To predict evolutionary stable strategies for sex allocation under varying stress conditions.

Main Methods:

• Theoretical modeling of sex allocation in hermaphrodites.
• Analysis of resource allocation trade-offs under environmental stress.
• Simulation of population dynamics with stressed and unstressed individuals.

Main Results:

• Sex allocation strategies are critically dependent on how stress affects the male-female reproduction cost trade-off.
• When stress affects a small population fraction, stressed individuals allocate to male function, unstressed to female.
• When stress affects a high population fraction, stressed individuals invest in sperm, unstressed in embryos.

Conclusions:

• Environmental stress significantly alters sex allocation strategies in simultaneous hermaphrodites.
• The proportion of stressed individuals influences the direction of resource allocation shifts.
• Populations with both stressed and unstressed hermaphrodites exhibiting simultaneous reproduction are unlikely in nature.