Extinction vs. Rapid Radiation: The Juxtaposed Evolutionary Histories of Coelotine Spiders Support the Eocene–Oligocene Orogenesis of the Tibetan Plateau

Abstract

Evolutionary biology has long been concerned with how changing environments affect and drive the spatiotemporal development of organisms. Coelotine spiders (Agelenidae: Coelotinae) are common species in the temperate and subtropical areas of the Northern Hemisphere. Their long evolutionary history and the extremely imbalanced distribution of species richness suggest that Eurasian environments, especially since the Cenozoic, are the drivers of their diversification. We use phylogenetics, molecular dating, ancestral area reconstructions, diversity, and ecological niche analyses to investigate the spatiotemporal evolution of 286 coelotine species from throughout the region. Based on eight genes (6.5 kb) and 2323 de novo DNA sequences, analyses suggest an Eocene South China origin for them. Most extant, widespread species belong to the southern (SCG) or northern (NCG) clades. The origin of coelotine spiders appears to associate with either the Paleocene-Eocene Thermal Maximum or the hot period in early Eocene. Tibetan uplifting events influenced the current diversity patterns of coelotines. The origin of SCG lies outside of the Tibetan Plateau. Uplifting in the southeastern area of the plateau blocked dispersal since the Late Eocene. Continuous orogenesis appears to have created localized vicariant events, which drove rapid radiation in SCG. North-central Tibet is the likely location of origin for NCG and many lineages likely experienced extinction owing to uplifting since early Oligocene. Their evolutionary histories correspond with recent geological evidence that high-elevation orographical features existed in the Tibetan region as early as 40-35 Ma. Our discoveries may be the first empirical evidence that links the evolution of organisms to the Eocene-Oligocene uplifting of the Tibetan Plateau. [Tibet; biogeography; ecology; molecular clock; diversification.].

Sinodraconarius gen. n., a new genus of Coelotinae spiders from Southwest China (Araneae, Agelenidae)

“…A partial fragment of the mitochondrial cytochrome oxidase subunit I (COI) gene was amplified and sequenced for all species, using the following primers: Forward: LCO1490-oono (5’-CWACAAAYCATARRGATATTGG-3’) and Reverse: C1-N-2776 (5’-GGATAATCAGAATANCGNCGAGG-3’). For additional information on extraction, amplification and sequencing procedures, see Zhao and Li (2017). All sequences were analyzed using BLAST and are deposited in GenBank.…”

“…In addition to morphological study, we analyzed the relationships of coelotine spiders using eight genes from 286 species in 19 genera (Zhao and Li 2017). The molecular topologies inferred by three different approaches all supported Sinodraconarius gen. n. as a monophyletic group that is closely related to Draconarius .…”

“…The molecular topologies inferred by three different approaches all supported Sinodraconarius gen. n. as a monophyletic group that is closely related to Draconarius . For details, please see SD001, SD002, SD019, SD028 and ZZ300 (Southern Coelotes groups) in Figure 3 and supplementary figures S4–S6 of Zhao and Li (2017).…”

“…Recent molecular studies suggested that Draconarius is polyphyletic and requires taxonomic rearrangements (Zhao and Li 2017). Here, we described a new genus, Sinodraconarius gen. n., with four new species.…”

Clonal diversity and substantial genetic divergence of the Daphnia similis species complex in Chinese lakes: Possible adaptations to the uplift of the Qinghai‐Tibetan Plateau

“…All these factors have contributed to the evolution of the Qinghai‐Tibetan Plateau as a biogeographic hotspot (e.g., Myers et al ; Xie et al ). Previous studies of biodiversity and biogeography in the region have focused on aquatic vertebrates (e.g., Zhao et al ; Ding et al ) and terrestrial invertebrates (Zhao and Li ). Very few studies have focused on the biogeography and genetic diversity of aquatic invertebrate zooplankton from the Qinghai‐Tibetan Plateau (Xu et al ; Ma et al , b ).…”