Offspring may succeed well next to their relatives, but it needs particular traits

Area of Science:

• Ecology
• Evolutionary Biology
• Plant Science

Background:

• Debate exists on whether offspring thrive near distantly related (fewer enemies) or closely related (more mutualists) adults.
• This study investigates how neighbor relatedness impacts offspring performance and trait-based success.

Purpose of the Study:

• To test the hypothesis that adult neighbor relatedness influences which traits confer offspring performance, rather than performance itself.
• To understand the role of trait-performance relationships in sessile oaks (Quercus petraea and hybrids) across varying neighbor relatedness.

Main Methods:

• Examined seed removal, germination, and sapling growth in sessile oaks.
• Manipulated offspring density, presence of insects/fungi, and proximity to related/unrelated oaks.
• Assessed trait-performance relationships under different neighbor relatedness conditions.

Main Results:

• Phylogenetic distance of neighbors had minimal impact on overall offspring performance.
• Neighbor relatedness significantly altered which traits (seed/sapling size, shape) conferred performance.
• Trait-performance relationships were largely explained by biotic interactions (insects, competitors), not environmental factors or gymnosperm presence.

Conclusions:

• Sessile oaks exhibit flexible adaptation to diverse neighborhoods via biotic micro-mosaic selection.
• The species may maintain potential for both niche convergence and divergence, influencing phylogenetic niche signal.
• Neighbor relatedness shapes adaptive trait expression in sessile oaks.