Data from: Horses in the Cloud: big data exploration and mining of fossil and extant Equus (Mammalia: Equidae)

Extant species of the genus Equus (e.g., horses, asses, and zebras) have a widespread distribution today on all continents except Antarctica. Extinct species of Equus represented by fossils were likewise widely distributed in the Pliocene and even more so during the Pleistocene. In order to understand the efficacy of “big data” for (paleo)biogeographic analyses, location records (latitude, longitude) and fossil occurrences for the genus Equus were mined and further explored from six databases, including iDigBio, Paleobiology Database, VertNet, BISON, Neotoma, and GBIF. These were chosen from a priori knowledge of where relevant data might be aggregated. We also realized that these databases have different objectives and data sources and therefore would provide a useful comparative study of the widespread taxon Equus in space and time. The mining of Equus data from these six sources yielded a combined total of 123.8 K location records, including 116.2K fossil specimens. These include individual points that are unique, that is, only occurring in one of these databases, and those that are duplicated in multiple databases. Of the six databases, three (iDigBio, Paleobiology Database, and GBIF) were judged to be the most useful in the Equus use case. Most of the databases are biased toward North American records, thus limiting the reconstruction of the actual distribution of the genus Equus in space and time outside of this continent. Although Equus has a large number of digitally accessible records, fundamentally interesting questions pertaining to evolutionary dynamics and extinction geography are still a challenge for these kinds of biodiversity databases due primarily to the lack of sufficiently dense and precise temporal data.马属（Equus）现存物种（如马、驴和斑马）如今除南极洲外，遍布全球各大陆。以化石记录为代表的马属已灭绝物种，在上新世时期便已有广泛分布，至更新世时期分布范围更为广阔。为探究“大数据”在（古）生物地理学分析中的应用效能，本研究从六大数据库——包括iDigBio、古生物学数据库（Paleobiology Database）、VertNet、BISON、Neotoma以及全球生物多样性信息设施（GBIF）——中挖掘并进一步梳理了马属物种的位置记录（纬度、经度）与化石出现数据。这些数据库的选取基于先验知识，即依据相关数据的常规聚集渠道进行筛选。同时，我们注意到各数据库的目标与数据来源存在差异，因此可针对广布分类群马属开展跨时空的对比研究，具备较高学术价值。从上述六大数据库中挖掘的马属数据总计达12.38万条位置记录，其中包含11.62万件化石标本。这些记录包含两类：一类为仅在单一数据库中出现的独有点位，另一类为在多个数据库中重复存在的点位。在六大数据库中，iDigBio、古生物学数据库（Paleobiology Database）与全球生物多样性信息设施（GBIF）这三个数据库被认为在马属研究场景中实用性最强。多数数据库的数据偏向北美地区的记录，这限制了对该属在北美以外区域的跨时空实际分布的重建工作。尽管马属拥有大量可数字化获取的记录，但针对演化动态与灭绝地理等核心科学问题的研究，仍是这类生物多样性数据库面临的一大挑战，这主要是因为缺乏足够密集且精确的时序数据。