Did the Quaternary climatic fluctuations really influence the tempo and mode of diversification in European rodents?

Abstract

The objective of this study was to establish whether the Quaternary climatic fluctuations influenced the tempo and mode of diversification in European rodents. Our case study is the subgenus Microtus (Terricola) distributed from western Europe to the Caucasus. Mitochondrial cytochrome b gene sequences from several representatives of all the species were used to generate maximum‐likelihood and Bayesian phylogenetic trees, to estimate divergence times, to identify biogeographic ancestral areas and to study the rate of diversification. Results showed that phylogenetic tree topologies were similar to previous published studies but with a better resolution at some nodes. The origin of Microtus (Terricola) is dated back to approximately 4.05 Myr in the Early Pliocene, and molecular dating for most Terricola species corresponds to several glacial periods of the Pleistocene. Results of the biogeographic ancestral area reconstruction suggest that Microtus (Terricola) diversified from the Caucasus/Turkey/Iran area through western Europe. Several periods of diversity variation were highlighted as follows: two period of diversity increase, between 3 and 2 Myr, and after 1 Myr; two periods of diversity decrease, before 3 Myr, and between 2 and 1 Myr. The diversification rate of Microtus (Terricola) was 0.353 ± 0.004 event/Myr, a rate similar to that of the Muridae family. To conclude, although the Pleistocene glacial conditions had an impact on the speciation events, the Quaternary does not appear however as a period with an exceptional rate of diversification for European rodents.

Mammal endemism In Italy: A review

“…Castiglia et al (2008) suggested a possible specific status of the Sicilian Microtus, then they confirmed this in further papers based on molecular genetics, karyotypic and morphological studies (Gornung et al 2011, Bezerra et al 2016. The split of this species with the other species of the complex, M. savii and M. brachycercus, dated about 1.81 million years ago (MYA) (Tougard 2017). Microtus brachycerchus (von Lehmann, 1961).…”

“…Its species status is supported by chromosomal and hybridological data (Galleni et al 1994). Genetic divergence with the sister species, M. savii, dated about 1.03 MYA (Tougard 2017).…”

“…This species resulted karyotypically different from M. brachycercus and male hybrids between the two species are steriles (see account for the sister species M. brachycercus). The divergence time with its sister species M. brachycerucs is 1.03 MYA (Tougard 2017).…”

A complex scenario of glacial survival in Mediterranean and continental refugia of a temperate continental vole species ( Microtus arvalis ) in Europe

“…This location is consistent with the oldest fossil remains of M. arvalis found in SW Germany (Kowalski, ) and relates closely to what (Tougard et al, ) proposed as the common cradle of M. arvalis in “western Central Europe.” Moreover, our date estimates for the root of the tree and of major lineages coincided with recent research (Stojak, McDevitt, et al, ). This scenario is clearly not consistent with the fossil evidence (oldest fossil remains of M. arvalis in Central Europe from the Late Cromerian, 465,000 ybp; (Kowalski, )) although accurate species identification in fossil remains appear to be problematic and should always be considered cautiously for this and related species (Navarro et al, ; Tougard, ). The extreme similarity between sibling vole species (Markova et al, ) and the morphological changes probably suffered by the species between the mid‐Holocene and the present day are known to be unfavorable for diagnosing M. arvalis in the fossil record (Markova, Beeren, van Kolfschoten, Strukova, & Vrieling, ).…”

Küçük Memeli Paleontolojisinin Türkiye’deki Kuvaterner Çalışmalarına Katkısı: Tanımlar ve Uygulamalar

“…Diğer taraftan, Kuvaterner boyunca iklimsel değişikliklerin etkisiyle kimi türlerin soğuk dönemlerde sığınma alanını oluşturur (glacial refugia), adaptasyonla yayılma (adaptive radiation) gösteren kimi türler için de bir koridor görevi üstlenir (örn. kör fareler, tarla fareleri, Anadolu yer sincabı gibi; Gür, 2013;Tougard, 2016). Kaldı ki, kimi yazarlara göre (Chaline, 1987) bu alanlar yeni türleşmelerin tetikleyicisidir.…”