Costs and Consequences of Plasticity

Production Costs: The energetic costs of producing a plastic phenotype, specifically the shifting of a response. It can be hard to demonstrate since producing a flexible phenotype has to be costly.
Maintenance Costs: Maintaining the sensory machinery required to detect environmental changes and initiate a plastic response. Includes genes to sense environmental changes.
Information Acquisition Costs: Costs associated with actively sensing the environment (e.g., energy expenditure for predator detection).
Developmental Instability: Imperfect phenotypic changes during development. Results in issues like fluctuating asymmetry (e.g., wonky wing shape affecting flight).
Genetic Costs: Alleles coding for plasticity may have links to lower fitness. The negative interactions between genes/alleles (epistasis) influence fitness.
Limits to Benefits: Occur due to unreliable information, lag time limits if environment fluctuates too fast. The plastic response may not be fast enough or the right response.

Fixed responses are sometimes better than plastic adjustments. It might be better to produce one fixed phenotype than a phenotype that can change. Epiphenotype problem: fixed phenotype might be better in a different way.

The species with the highest tolerance from the warmest habitats didn't show the biggest response, but showed the smallest response.
Species with low initial tolerance from cooler habitats could show a plastic response.
Species with a higher tolerance had the highest responses. Species with the low tolerance had low responses.

Behavioral responses to environmental stressors, such as the presence of predators or pesticides, can have unexpected effects on survival and development.

Plastic responses can persist across generations via epigenetics (no gene change) or maternal effects.
Example: Daphnia producing head spikes in response to a chemical cue from predators. The effect diminishes in the second generation.
Example: Bryozoan species exposed to copper:
- Parents exposed to copper pass on resistance to their offspring.
- No genetic change or selection is involved.
- Offspring of exposed parents show lower fitness in clean water.

Predator-prey oscillations can be stabilized by plasticity in prey species (e.g., phytoplankton producing defensive chemicals).
Plasticity can influence species interactions:
- Wood frogs hide from predators, decreasing growth rate and competitive ability with leopard frogs.
- Crabs cause snails to hide, affecting algae density due to reduced grazing.