Turning induced plasticity into refined adaptations during range expansion

Area of Science:

• Evolutionary biology
• Physiological ecology
• Developmental biology

Background:

• Organisms must balance robustness to environmental fluctuations with the capacity for novel adaptations (evolvability).
• Feather structure and carotenoid uptake represent a key adaptation in many bird species, influenced by environmental conditions.
• Understanding the mechanisms underlying transitions between robustness and evolvability is crucial for predicting evolutionary trajectories.

Purpose of the Study:

• To investigate how robustness and evolvability are reconciled during adaptive transitions.
• To examine the coevolution of feather structure and carotenoid uptake in response to environmental change.
• To elucidate the role of stress-buffering mechanisms in facilitating new adaptations.

Main Methods:

• Studied transitions between adaptive associations of feather structure and carotenoid uptake.
• Analyzed feather modifications induced by novel carotenoids during population range expansion.
• Investigated changes in the sensitivity of feather development to local carotenoid uptake.

Main Results:

• Feather modifications induced by new carotenoids were converted into precise coadaptations of feather development and carotenoid accommodation.
• Populations showed a uniform and coordinated increase in the sensitivity of feather development to local carotenoid uptake.
• This conversion suggests cooption and modification of homeostatic mechanisms buffering feather growth.

Conclusions:

• Stress-buffering mechanisms can effectively alternate between robustness and evolvability.
• This interplay is particularly evident in adaptations requiring integration of external inputs and internal structures.
• The findings provide insights into the evolution of complex adaptations under fluctuating environments.