Evolution of multiple competitors; experimental evolution using a natural protozoan community.

这项研究将检验生态学中一个长期存在的概念，即如果两个物种利用非常相似的资源，其中一个或两个物种将进化成使用不同的资源，或者其中一个将在当地灭绝。这个概念是我们理解生物群落是如何组织的基础。利用在猪笼草充满水的叶子中发现的微生物，该项目将测试这一原理及其对物种相互作用如何进化的预测。一种新的实验方法将被用来比较在物种多样性增加的群落中发生的多种物种的进化。许多群落生态学假设每个物种都有自己理想的生态角色，称为生态位，并且进化可以导致物种改变其生态位以限制来自其他物种的资源竞争。达尔文的雀类提供了一个很好的例子，这些鸟类在岛屿上一起进化时，与它们单独生活时相比，差异更大。然而，在许多物种可能同时进化的复杂群落中，关于生态位进化的预测变得更加困难。除了进行涉及猪笼草微生物群落的温室实验外，pi还将培训本科生和研究生，并开展针对佛罗里达州科学标准的教育活动。这项工作将解决长期存在的假设，即竞争导致生态位划分和特征位移。利用温室中生长的猪笼草，对1种、2种和4种群落的原生动物物种进化模式进行了量化。这个设计可以用来询问物种是否在日益复杂的群落中进化得不同。生态位划分理论被认为是导致共存的理论，如果物种共同进化减少竞争相互作用，将得到支持，而如果在多物种系统中进化增加竞争相互作用，将支持生态位趋同。与原生动物进食有关的细胞大小和其他物理特征等具体特征也将被量化。下一代DNA测序将用于量化不同组合的原生动物如何影响潜在的细菌群落。

This study will test a long-standing concept in ecology that if two species utilize very similar resources, either one or both will evolve to use different resources, or one will be driven locally extinct. This concept is foundational to our understanding of how biological communities are organized. Using microbes found in the water-filled leaves of pitcher plants, this project will test this principle and its predictions about how species interactions evolve. A novel experimental approach will be used that compares the evolution of multiple species occurring in communities of increasing species diversity. Much of community ecology assumes that each species has its own ideal ecological role, called the niche, and that evolution can lead species to change their niche to limit resource competition from other species. Darwin's finches provide a good example, where these bird species evolved to be more different when together on islands, as compared to when they were alone. However, predictions about the evolution of the niche become more difficult in complex communities where many species may evolve at the same time. In addition to conducting greenhouse experiments involving pitcher plant microbial communities, the PIs will train undergraduate and graduate students as well as develop educational activities that target Florida science standards. This work will address long-standing hypotheses that competition leads to niche partitioning and character displacement. The evolutionary patterns of protozoa species will be quantified in 1-, 2, and 4-species communities, using pitcher plants grown in the greenhouse. This design can be used to ask if species evolve differently in communities of increasing complexity. The theory of niche partitioning, which is thought to lead to coexistence, will be supported if species co-evolve to have reduced competitive interactions, while niche convergence would be supported if increased competitive interactions evolve in multispecies systems. Specific traits such as cell size and other physical characteristics associated with feeding in the protozoa will also be quantified. Next-generation DNA sequencing will be used to quantifying how the protozoa evolving in different combinations affect the underlying bacterial community.