Intraspecific character displacement in oaks.

Area of Science:

• Evolutionary Biology
• Ecology
• Genetics

Background:

• Character displacement explains species divergence due to competition.
• Intraspecific character displacement (ICD) is a less-studied mechanism for divergence within species.
• Competition can influence intraspecific competition and drive the evolution of alternative phenotypes.

Purpose of the Study:

• Investigate how competition affects genetic and morphological differentiation within species in sympatric and allopatric populations.
• Analyze divergence in Quercus serrata and Q. serrata var. brevipetiolata.
• Explore resource-use strategies and ecological divergence driven by ICD.

Main Methods:

• Genetic markers to detect population divergence and gene flow.
• Geometric morphometric method (GMM) and traditional methods for leaf morphology analysis.
• Analysis of trait variation in relation to environmental factors.

Main Results:

• Detected genetic divergence between Chinese and Japanese populations of Q. serrata, with diversification within China.
• Leaf morphological variation was greater in sympatric populations compared to allopatric ones.
• Q. serrata var. brevipetiolata showed resource-conservative leaf traits in sympatry, indicating potential ecological divergence.

Conclusions:

• Intraspecific character displacement plays a key role in morphological diversification within species.
• Competition in sympatry influences resource-use strategies, favoring more conservative traits in later-diverged varieties.
• Results suggest Q. serrata var. brevipetiolata is undergoing ecological divergence from Q. serrata.