Evolution of the latitudinal diversity gradient in the hyperdiverse ant genus Pheidole
Evolution of the latitudinal diversity gradient in the hyperdiverse ant genus Pheidole
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DOI：
10.1111/geb.12867
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发表时间：
2019-04-01
影响因子：
6.4
通讯作者：
Knowles, L. Lacey
中科院分区：
文献类型：
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作者：
Economo, Evan P.;Huang, Jen-Pan;Knowles, L. Lacey
纬度多样性梯度是地球上生命的主要地理格局，但对其起源的共识仍然难以捉摸。最近分歧，超丰富的无脊椎动物群体的分析提供了一个机会，调查纬度模式与大树的统计能力，同时尽量减少潜在的混淆变化的生态和历史。在这里，我们综合了全球系统发育和宏观生态数据的超多样性（> 1,100种）的蚂蚁辐射，Pheidole和测试预测的纬度梯度的三个一般解释：多样化率的变化，热带保守主义和生态调节。位置全球。时间段过去的3500万年。主要分类群研究的超多样性蚂蚁属Pheidole Westwood。方法收集了1,499种和形态种的地理资料，并对449种的系统发育进行了推断，其中包括167种新的系统发育序列。我们测试了多样化率和纬度之间的相关性与贝叶斯分析的宏观进化混合物（BAMM），隐藏状态的物种形成和灭绝（HiSSE），地理状态的物种形成和灭绝（GeoSSE），和非参数方法（FiSSE），评估的证据丰富的稳定状态，并检查模式的多样化作为Pheidole传播到地球仪。结果没有证据表明任何方法的净多样化率随纬度的系统性变化。我们发现，当新大陆被殖民时，Pheidole多样化发生在爆发中，随后每个地区的增长速度都有所放缓，但没有证据表明任何地区的丰富度都达到了平衡。此外，我们发现纬度亲和力与新热带祖先适度保守，模拟表明仅系统发育惯性就足以产生梯度模式。主要结论我们的研究结果没有提供证据表明，多样化率随纬度系统地变化。尽管有证据表明，在新的地区殖民化后，生态机会促进了多样化，但与生态调节假说相反，每个地区的富裕程度远未达到稳定状态。生态位保守性强到足以产生梯度格局的事实与热带保守性假说雅阁。总的来说，这些结果揭示了在过去3400万年内出现的多样性梯度的机制，补充了最近的工作更深的时间尺度，更普遍地促进急需的无脊椎动物的角度对全球生物多样性动态。
Aim The latitudinal diversity gradient is the dominant geographic pattern of life on Earth, but a consensus understanding of its origins has remained elusive. The analysis of recently diverged, hyper-rich invertebrate groups provides an opportunity to investigate latitudinal patterns with the statistical power of large trees while minimizing potentially confounding variation in ecology and history. Here, we synthesize global phylogenetic and macroecological data on a hyperdiverse (> 1,100 species) ant radiation, Pheidole and test predictions of three general explanations for the latitudinal gradient: variation in diversification rates, tropical conservatism and ecological regulation. Location Global. Time period The past 35 million years. Major taxa studied The hyperdiverse ant genus Pheidole Westwood. Methods We assembled geographic data for 1,499 species and morphospecies, and inferred a dated phylogeny for 449 species of Pheidole, including 167 species newly sequenced for this study. We tested for correlations between diversification rate and latitude with Bayesian analysis of macroevolutionary mixtures (BAMM), hidden state speciation and extinction (HiSSE), geographic state speciation and extinction (GeoSSE), and a non-parametric method (FiSSE), evaluated evidence for richness steady state, and examined patterns of diversification as Pheidole spread around the globe. Results There was no evidence of systematic variation of net diversification rates with latitude across any of the methods. We found that Pheidole diversification occurred in bursts when new continents were colonized, followed by a slowdown in each region, but there is no evidence richness has saturated at an equilibrium in any region. Additionally, we found latitudinal affinity is moderately conserved with a Neotropical ancestor and simulations show that phylogenetic inertia alone is sufficient to produce the gradient pattern. Main conclusions Our results provide no evidence that diversification rates vary systematically with latitude. Richness is far from steady state in each region, contrary to the ecological regulation hypothesis, although there is evidence that ecological opportunity promotes diversification after colonization of new areas. The fact that niche conservatism is strong enough to produce the gradient pattern is in accord with the tropical conservatism hypothesis. Overall, these results shed light on the mechanisms underlying the emergence of the diversity gradient within the past 34 million years, complementing recent work on deeper time-scales, and more generally contribute toward much-needed invertebrate perspective on global biodiversity dynamics.