Phenotypic Constraints and Community Structure: Linking Intraspecific and Interspecific Tradeoffs

相互竞争的功能之间的权衡使任何一个有机体都无法在所有环境中脱颖而出，从而促进自然群落的多样性。在索诺兰沙漠，生长速度和耐旱性之间的权衡有助于冬季一年生植物的共存。该项目的目标是确定在不同物种之间观察到的这种权衡是否反映了在所有物种中运行的更深层次的约束。研究人员将在温室操作水资源可获得性的情况下比较干旱梯度上的种群，并使用受控育种来估计生长和耐旱性的遗传限制。在物种内的生长和耐旱性之间的权衡将表明，根本的限制限制了植物的生产力和抗逆性。如果这种权衡在物种内部并不明显，那么竞争等生态过程创造了构建群落的关键权衡。这个项目将揭示人口和社区对气候变化反应的潜在制约。概念框架还可以扩展到调查为什么一些非本土物种成为威胁生物多样性的入侵者，而另一些物种则不是。该项目将通过支持一名职业早期女性的研究计划，并为来自代表性不足群体的本科生提供培训和指导，为NSF促进教育和多样性的目标做出贡献。

Trade-offs between competing functions prevent any one organism from excelling in all environments, promoting diversity in natural communities. In the Sonoran Desert, a trade-off between growth rate and drought tolerance contributes to coexistence among winter annual plants. The goal of this project is to determine whether this trade-off observed across disparate species reflects a deeper constraint operating within all species. Researchers will compare populations from across an aridity gradient in a greenhouse manipulation of water availability and use controlled breeding to estimate genetic constraints on growth and drought tolerance. A trade-off between growth and drought tolerance within species would indicate that fundamental constraints limit plant productivity and stress tolerance. If the trade-off is not apparent within species, then ecological processes such as competition create the key trade-off that structures the community.This project will reveal potential constraints on population and community responses to climate change. The conceptual framework can also be extended to investigate why some non-native species become invaders that threaten biodiversity while others do not. The project will contribute to NSF goals for fostering education and diversity by supporting the research program of an early-career woman and providing training and mentorship for undergraduates from underrepresented groups.