Developmental plasticity reveals hidden fish phenotypes and enables morphospace diversification

Area of Science:

• Evolutionary biology
• Developmental biology
• Ecology

Background:

• Phenotypic variation arises from developmental plasticity, allowing organisms to adapt to new environments.
• Understanding how environmental stimuli influence phenotypic diversification is crucial for evolutionary studies.

Purpose of the Study:

• To investigate the role of developmental plasticity in generating new phenotypes and diversifying the morphospace of Megaleporinus macrocephalus.
• To assess phenotypic diversification at both the species and family levels within Anostomidae.

Main Methods:

• Raising Megaleporinus macrocephalus fish under diverse environmental conditions.
• Analyzing morphospace occupation and head bone morphology of plastic morphotypes.
• Comparing results with control populations and other Anostomidae species.

Main Results:

• Developmental plasticity rapidly generated distinct head morphotypes previously hidden in the monomorphic parental population.
• Plastic morphotypes occupied unique, previously unfilled regions of the morphospace.
• Environmental influences induced adjustments in head bone shape and position, mimicking patterns of different genera.

Conclusions:

• Developmental plasticity is a significant driver of morphospace diversification and the emergence of novel phenotypes.
• Plastic responses in Megaleporinus macrocephalus contribute to adaptive radiation within the Anostomidae family.
• This study highlights how environmental plasticity shapes evolutionary trajectories.