Data from: Diversification across the New World within the ‘blue’ cardinalids (Aves: Cardinalidae)

Aim: To examine the history of diversification of ‘blue’ cardinalids (Cardinalidae) across North and South America. Location: North America (including Middle America) and South America. Methods: We collected 163 individuals of the 14 species of blue cardinalids and generated multilocus sequence data (3193 base pairs from one mitochondrial and three nuclear genes) to infer phylogeographical structure and reconstruct time-calibrated species trees. We then estimated the ancestral range at each divergence event and tested for temporal shifts in diversification rate. Results: Twenty-five lineages of blue cardinalids clustered into two major clades: one confined to North America, and a second concentrated in South America. Blue cardinalids probably originated in North America, but reconstructions were influenced by how migrant taxa were assigned to biogeographical regions. Most of the pre-Pleistocene divergences between extant taxa occurred in the North American clade, whereas most divergences in South America and adjacent Middle America occurred during the Pleistocene. Despite these differences, the rate of diversification for both clades has been similar and relatively constant over the past 10 million years, with little geographical exchange between North and South America outside the Panamanian isthmus region. Main conclusions: Our reconstruction of the diversification history of blue cardinalids indicates a role of both Neogene and Quaternary events in generating biotic diversity across North and South America. Although ancestral area reconstruction suggests a possible North American origin for blue cardinalids, the occurrence of seasonal migration in this group and their relatives limits inference. Our study highlights the importance of considering ecological and behavioural characteristics together with palaeogeological events in order to gain an understanding of the diversification history of widespread, mobile taxonomic groups.研究目的：探究分布于北美洲与南美洲的“蓝色”主红雀科（Cardinalidae）类群的演化分化历史。研究区域：北美洲（含中美洲）及南美洲。方法：本研究采集了14种蓝色主红雀科类群共163个个体，生成了多位点序列数据（包含1个线粒体基因与3个核基因，总计3193个碱基对），以推断其系统地理学结构并重建时间校准的物种树。随后，我们估算了每次分化事件的祖先分布范围，并检验了分化速率的时间变化趋势。结果：25个蓝色主红雀科类群分支可聚类为两大演化支：一支局限于北美洲，另一支主要分布于南美洲。蓝色主红雀科类群大概率起源于北美洲，但祖先分布区重建结果受迁徙类群生物地理区域归属方式的影响。现存类群中绝大多数更新世之前的分化事件发生于北美演化支，而南美洲及邻近中美洲的多数分化事件则发生于更新世时期。尽管存在上述差异，两大演化支的分化速率在过去1000万年中始终相似且相对稳定，除巴拿马地峡区域外，南北美洲之间几乎无地理分布范围的交换。主要结论：本研究对蓝色主红雀科类群分化历史的重建表明，新近纪（Neogene）与第四纪（Quaternary）事件均在塑造南北美洲生物多样性的过程中发挥了作用。尽管祖先分布区重建提示蓝色主红雀科类群可能起源于北美洲，但该类群及其近缘类群存在季节性迁徙的特性，这限制了推论的准确性。本研究强调，若要全面理解分布广泛、具有移动能力的类群的分化历史，需同时结合生态学、行为学特征与古地质事件进行综合考量。