Linking conceptual mechanisms and transcriptomic evidence of plasticity-driven diversification

Area of Science:

• Evolutionary biology
• Developmental biology
• Genomics

Background:

• East African cichlids exemplify adaptive radiation, with diversification linked to diet and morphology.
• Developmental plasticity in jaw ecomorphs aids niche exploitation and diversification.
• Understanding molecular mechanisms of plasticity is crucial for linking it to phenotypic divergence.

Purpose of the Study:

• To identify the transcriptional mechanisms underlying diet-induced lower pharyngeal jaw (LPJ) plasticity in Astatoreochromis alluaudi.
• To investigate the molecular basis of jaw ecomorph development in response to varying diets.

Main Methods:

• Dietary manipulations were used to induce developmental plasticity in A. alluaudi jaws.
• Transcriptomic profiles of the resulting lower pharyngeal jaw (LPJ) morphs were compared.

Main Results:

• 187 differentially expressed genes were identified, underlying the development and maintenance of diet-induced LPJ morphologies.
• These genes include transcription factors, signaling molecules, and structural genes.

Conclusions:

• This study provides foundational insights into the molecular mechanisms of diet-induced jaw plasticity in cichlids.
• The findings contribute to understanding how plasticity influences evolutionary diversification.