Iberian Plio‐Pleistocene biochronology: micromammalian evidence for MNs and ELMAs calibration in southwestern Europe

Abstract

A multivariate biochronological analysis of the Plio-Pleistocene Iberian rodent fossil record is presented. Among more than 300 fossil sites, 49 sites have been selected. The ordination of the fossil sites selected from the Iberian Peninsula has been achieved by the appearance event ordination method. After calibration of this ordination with geochronological dates at some of the localities, numerical dates are proposed for all the localities studied. Hence, mammal fossil sites non-datable by other means (palaeomagnetism, radiometric dating, etc.) have been dated with a relatively high degree of confidence. Final results allow dating of boundaries between the Plio-Pleistocene European Land Mammal Ages (ELMAS) or the Mammal Neogene (MN) units. These boundaries agree with previous studies using magnetostratigraphical calibration of these scales.

Global climate changes drive ecological specialization of mammal faunas: trends in rodent assemblages from the Iberian Plio-Pleistocene

“…In this work we used the faunal lists of rodent communities from 44 fossil sites from the Iberian Plio-Pleistocene (Table 1) dated between 5.25 and 0.01 Ma [38]. These fossil sites have been subject to intensive sampling during the last fifty years (see references in [38]).…”

“…These fossil sites have been subject to intensive sampling during the last fifty years (see references in [38]). The minimum sample required to include a fossil site in our study was 100 first and second upper and lower molars, which is considered the minimum number necessary to render a representative sample of the original paleocommunity [30,36,39].…”

Biogeographic provincialism in rodent faunas from the Iberoccitanian Region (southwestern Europe) generates severe diachrony within the Mammalian Neogene (MN) biochronologic scale during the Late Miocene

“…The analysis does not consider species exclusive to one locality, known as singletons. A new version named Appearance Event Ordination (AEO; Alroy, 1994) makes it possible to include available information on stratigraphic superposition between fossil localities (Wing et al, 1995;Hernandez Fernandez et al, 2004;Hammer and Harper, 2006). This software calculates for each faunal list the First Appearance Event (FAE) of one species with regard to the Last Appearance Event (lAE) of another.…”

“…Several authors have suggested the inclusion of some additional fossil sites in the analysis to avoid mathematical anomalies, which affect the boundaries of the temporal distribution studied Hernandez Fernandez et al, 2004;Domingo et al, 2007). Therefore, in order to polarize the upper end of the sequence, we included some fossil sites from MN 14 (Caravaca 1, Celadas 9, Gorafe 1, La Gloria 4, Peralejos E and Purcal 4 for the southern province; Celleneuve, Font Estramar, Hautimagne and Vendargues for the northern province), which are younger than the study interval being analyzed.…”

“…These statistical tools use all the taxa described in a fossil site, and can be very useful for dating some stratigraphically isolated localities or sites where no characteristic taxa are found (Azanza et al, 1997a;van Dam, 2003;Fortelius et al, 2006). For example, the Maximum Likelihood Appearance Event Ordination (ML AEO; Alroy, 2000) has been used in biochronological studies of Cenozoic mammals from North America (Alroy, 1992(Alroy, , 1994, South America (Prado et al" 2001), Africa (Alroy, 1994) and Europe (Azanza et aI., 1997b;Hernandez Fernandez et al, 2004;Domingo et al, 2007). The ML AEO allows ordination of fossil sites according to values (AEO coefficients) obtained on the basis of their faunal lists.…”