Data from: Phylogenetic diversity and coevolutionary signals among trophic levels change across a habitat edge

1. Incorporating the evolutionary history of species into community ecology enhances understanding of community composition, ecosystem functioning and responses to environmental changes. 2. Phylogenetic history might partly explain the impact of fragmentation and land-use change on assemblages of interacting organisms, and even determine potential cascading effects across trophic levels. However, it remains unclear whether phylogenetic diversity of basal resources is reflected at higher trophic levels in the food web. In particular, phylogenetic determinants of community structure have never been incorporated into habitat edge studies, even though edges are recognised as key factors affecting communities in fragmented landscapes. 3. Here we test whether phylogenetic diversity at different trophic levels (plants, herbivores, parasitoids) and signals of coevolution (i.e. phylogenetic congruence) among interacting trophic levels change across an edge gradient between native and plantation forests. To ascertain whether there is a signal of coevolution across trophic levels, we test whether related consumer species generally feed on related resource species. 4. We found differences across trophic levels in how their phylogenetic diversity responded to the habitat edge gradient. Plant and native parasitoid phylogenetic diversity changed markedly across habitats, while phylogenetic variability of herbivores (which were predominantly native) did not change across habitats, though phylogenetic evenness declined in plantation interiors. Related herbivore species did not appear to feed disproportionately on related plant species (i.e. there was no signal of coevolution) even when considering only native species, potentially due to the high trophic generality of herbivores. However, related native parasitoid species tended to feed on related herbivore species, suggesting the presence of a coevolutionary signal at higher trophic levels. Moreover, this signal was stronger in plantation forests, indicating that this habitat may impose stresses on parasitoids that constrain them to attack only host species for which they are best adapted. 5. Overall, changes in land use across native to plantation forest edges differentially affected phylogenetic diversity across trophic levels, and may also exert a strong selective pressure for particular coevolved herbivore-parasitoid interactions.

1. 将物种进化历史纳入群落生态学(community ecology)研究，可深化对群落组成(community composition)、生态系统功能(ecosystem functioning)以及群落对环境变化响应的认知。
2. 系统发育历史(phylogenetic history)或可部分解释生境片段化与土地利用变化对互作生物群落的影响，甚至能决定跨营养级(trophic levels)的潜在级联效应。然而，目前仍不清楚食物网中基础资源的系统发育多样性(phylogenetic diversity)是否会在更高营养级得到体现。尤为关键的是，尽管生境边缘被认为是影响破碎化景观中群落的关键因素，但群落结构的系统发育决定因素从未被纳入生境边缘效应研究。
3. 本研究旨在检验不同营养级（植物、植食性昆虫、寄生蜂）的系统发育多样性，以及互作营养级间的共进化(coevolution)信号（即系统发育一致性(phylogenetic congruence)）是否会随原生林与人工林之间的边缘梯度发生变化。为明确营养级间是否存在共进化信号，我们检验了亲缘关系较近的消费者物种是否普遍取食亲缘关系较近的资源物种。
4. 研究发现，不同营养级的系统发育多样性对生境边缘梯度的响应存在差异。植物与本土寄生蜂的系统发育多样性在不同生境中变化显著，而（以本土物种为主的）植食性昆虫的系统发育变异性并未随生境改变，但其系统发育均匀度(phylogenetic evenness)在人工林内部有所下降。亲缘关系较近的植食性昆虫并未不成比例地取食亲缘关系较近的植物物种（即未检测到共进化信号），即便仅考虑本土物种亦是如此，这可能源于植食性昆虫较高的营养泛化性(trophic generality)。然而，亲缘关系较近的本土寄生蜂物种往往会取食亲缘关系较近的植食性昆虫物种，这表明在更高营养级存在共进化信号。此外，该信号在人工林中更为强烈，这表明该生境可能会对寄生蜂施加选择压力，使其仅能攻击自身最适应的寄主物种(host species)。
5. 总体而言，从原生林到人工林的边缘地带土地利用变化，会对不同营养级的系统发育多样性产生差异化影响，同时可能会对特定的植食性昆虫-寄生蜂互作的共进化关系施加强烈的选择压力。