Phenotypic Constraints and Community Structure: Linking Intraspecific and Interspecific Tradeoffs

相互竞争的功能之间的权衡阻止任何一种生物在所有环境中都表现出色，从而促进了自然群落的多样性。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中观察到的这种权衡是否反映了在所有物种中运作的更深层次的约束。研究人员将在温室中对不同干旱梯度的种群进行比较，并利用控制育种来估计对生长和耐旱性的遗传限制。物种生长和耐旱性之间的权衡表明，基本的制约因素限制了植物的生产力和耐旱性。如果这种权衡在物种内部并不明显，那么竞争等生态过程就会创造出构建群落的关键权衡。该项目将揭示人口和社区应对气候变化的潜在制约因素。这个概念框架也可以扩展到调查为什么一些非本地物种成为威胁生物多样性的入侵者，而另一些却没有。该项目将通过支持早期职业女性的研究项目，并为来自代表性不足群体的本科生提供培训和指导，为国家科学基金会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.