Diversification in tropics and subtropics following the mid‐Miocene climate change: A case study of the spider genusNesticella

Abstract

Caves may offer suitable refugia for troglophilic invertebrates during periods of unfavourable climatic conditions because of their stable microclimates. As a consequence, allopatric divergence from their epigean counterparts may occur, leading to formation of truly hypogean communities (the Climatic Relict Hypothesis). Unlike the well-studied effects of Pleistocene glaciations, we know little about how ancient climate changes drove the development of cave-dwelling organisms living at both middle and lower latitudes. We investigate the evolutionary history of the troglophilic spider genus Nesticella (Araneae, Nesticidae) in relation to Asian Neogene (23-2.6 Ma) climatic changes. Our analyses discern clear differences in the evolution of the two main clades of Nesticella, which occur in temperate/subtropical and tropical latitudes. Eastern Asian Nesticella gradually evolved greater sedentariness and a strict subterranean lifestyle starting from the middle Miocene Epoch (~15-14 Ma) in conjunction with the progressive deterioration of the climate and vegetational shifts. Caves appear to have acted as refugia because of their internally uniform temperature and humidity, which allowed these spiders to survive increasing external seasonality and habitat loss. In contrast, a uniform accumulation of lineages, long-lasting times for dispersals and the lack of a comparable habitat shifting characterized the tropical lineage. This difference in pattern likely owes to the mild effects of climate change at low latitudes and the consequent lack of strong climatic drivers in tropical environments. Thus, the mid-Miocene climatic shift appears to be the major evolutionary force shaping the ecological differences between Asian troglophilic invertebrates and the driver of the permanent hypogean communities in middle latitudes.

Eocene–Oligocene sea‐level fall drove amphipod habitat shift from marine to freshwater in the Far East

“…The Sea of Japan opened with a “double door” movement, the islands in north‐eastern Japan rotated counterclockwise by 47° and the islands in south‐western Japan rotated 56° clockwise (Isozaki et al, ; Otofuji, Matsuda, & Nohda, ). Similar diversification patterns have been documented in other groups, such as Hynobius salamanders (Li et al, ) and spiders (Ballarin & Li, ).…”

Finding answers in the dark: caves as models in ecology fifty years after Poulson and White

“…Spatial modelisation None that past climatic changes drove surface-dwelling species to colonize subterranean habitats, causing their isolation (Jeannel 1943, Peck 1980, Holsinger 1988, Botosaneanu and Holsinger 1991) and shaping their current ranges of distribution (Foulquier et al 2008, Allegrucci et al 2011, Niemiller et al 2013b, Mammola et al 2015b. Some authors have also demonstrated how more ancient climatic upheavals, such as those that occurred in the Miocene epoch, were involved in driving subterranean colonization (Leys et al 2003, Faille 2010, Mammola et al 2015b, Ballarin and Li 2017. For instance, it is observed that an obligate subterranean fauna is nearly absent from areas which have been covered by conspicuous ice masses during the last glacial maximum (Holdhaus 1932, Latella et al 2012, Ružička et al 2013, Mammola et al 2018b.…”

“…For instance, it is observed that an obligate subterranean fauna is nearly absent from areas which have been covered by conspicuous ice masses during the last glacial maximum (Holdhaus 1932, Latella et al 2012, Ružička et al 2013, Mammola et al 2018b). Some authors have also demonstrated how more ancient climatic upheavals, such as those that occurred in the Miocene epoch, were involved in driving subterranean colonization (Leys et al 2003, Faille 2010, Mammola et al 2015b, Ballarin and Li 2017. Past climatic oscillations and historic factors are also known to be important determinants of subterranean species range size and current distribution patterns (Stoch andGalassi 2010, Zagmajster et al 2014).…”

The first record of the introduced spider species Nesticella mogera (Yaginuma, 1972) from Russia (Aranei: Nesticidae)

“…According to Ballarin & Li [2017], the mogera species group of the genus Nesticella was originally distributed in mainland China, separated from other species groups of the north-clade some 24 m.y.a. This hypothesis describes the continued stagnation of this group in the indigenous territory and the resettlement northward to Korea and from there eastward to Japan.…”

“…Unfortunately, Marusik's hypothesis about the ancient Caucasian-Far East disjunctive range of N. mogera [Marusik, Guseinov, 2003] was not discussed by Ballarin & Li [2017]. Yet, the disjunctive type of species distribution is not unique.…”