Time for speciation and niche conservatism explain the latitudinal diversity gradient in clupeiform fishes
Time for speciation and niche conservatism explain the latitudinal diversity gradient in clupeiform fishes
复制标题
DOI：
10.1111/jbi.14465
复制
发表时间：
2022-07-31
影响因子：
3.9
通讯作者：
Simons，Andrew M.
中科院分区：
文献类型：
--
作者：
Egan，Joshua P.;Bloom，Devin D.;Simons，Andrew M.
目的从两极到赤道物种丰富度增加的纬度多样性梯度是生物多样性最引人注目和最普遍的空间格局之一。气候似乎是纬度多样性梯度形成的关键，但气候塑造物种丰富度的过程仍不清楚。我们测试的时间预测的物种形成，承载能力和多样化率纬度多样性梯度假设在一个跨海洋/淡水的fish.LocationGlobal在海洋和淡水环境中的分支。TaxonClupeiformes（鲱鱼，鲱鱼，沙丁鱼和亲属）。MethodsWe测试预测的纬度多样性梯度假设使用分子生物学，物种分布数据和系统发育比较方法。为了检验物种形成假说的时间，我们进行了祖先状态重建，以推断温带，亚热带和热带血统的年龄和气候之间的进化过渡的频率。我们通过描述净多元化率随时间的变化来检验承载能力假设。为了检验多样化率假说，我们定性比较了温带，亚热带和热带血统的多样化率和纬度和多样化率之间的关联进行统计检验results我们确定了四个过渡到温带气候和两个过渡出温带气候。我们没有发现温带和热带clupeiforms之间的多样化率的差异。自热带和温带谱系起源约150 Ma以来，冠鲱形目的净多样化率一直保持正值。气候生态位特征具有较强的系统发育信号。所有温带clupeiform谱系出现<50 Ma后，早始新世Climatic optimit.Main conclusionsOur结果支持的时间为物种形成假说，提出气候生态位保守性和波动的程度，温带气候限制的时间物种积累在温带气候，导致纬度多样性梯度。我们发现没有支持的承载能力或多样化率的假设。
AimThe latitudinal diversity gradient of increasing species richness from poles to equator is one of the most striking and pervasive spatial patterns of biodiversity. Climate appears to have been key to the formation of the latitudinal diversity gradient, but the processes through which climate shaped species richness remain unclear. We tested predictions of the time for speciation, carrying capacity and diversification rate latitudinal diversity gradient hypotheses in a trans‐marine/freshwater clade of fishes.LocationGlobal in marine and freshwater environments.TaxonClupeiformes (anchovies, herrings, sardines and relatives).MethodsWe tested predictions of latitudinal diversity gradient hypotheses using a molecular phylogeny, species distribution data and phylogenetic comparative approaches. To test the time for speciation hypothesis, we conducted ancestral state reconstructions to infer the ages of temperate, subtropical and tropical lineages and frequency of evolutionary transitions between climates. We tested the carry capacity hypothesis by characterizing changes in net diversification rates through time. To test the diversification rate hypothesis, we qualitatively compared the diversification rates of temperate, subtropical and tropical lineages and conducted statistical tests for associations between latitude and diversification rates.ResultsWe identified four transitions to temperate climates and two transitions out of temperate climates. We found no differences in diversification rates among temperate and tropical clupeiforms. Net diversification rates remained positive in crown Clupeiformes since their origin ~150 Ma in both tropical and temperate lineages. Climate niche characters exhibited strong phylogenetic signal. All temperate clupeiform lineages arose <50 Ma, after the Early Eocene Climatic Optimum.Main conclusionsOur results support the time for speciation hypothesis, which proposes that climate niche conservatism and fluctuations in the extent of temperate climates limited the time for species to accumulate in temperate climates, resulting in the latitudinal diversity gradient. We found no support for the carrying capacity or diversification rate hypotheses.