Abstract. To examine phylogenetic
relationships within the Asian lineage of voles (Microtus) belonging
to
subgenus Alexandromys,
the mitochondrial cytochrome b gene (cytb) was
sequenced for its representatives, and the results were compared with
the cytogenetic, morphological, and paleontological data. In all the
trees inferred from maximum likelihood, parsimony, and Bayesian
phylogenetic analyses, the Asian clade is subdivided into highly
supported
Alexandromys
s.s. and moderately supported Pallasiinus
lineages. Four
subclades are recovered within Alexandromys:
(1) Microtus
maximowiczii
and Microtus
sachalinensis; (2) Microtus
miiddendorffii s.l., Microtus
mongolicus and Microtus
gromovi; (3) Microtus
fortis; and (4) Microtus
limnophilus. Thus, M.
limnophilus demonstrates clear affinities to
Alexandromys
s.s. but not to Microtus
oeconomus (subgenus Pallasiinus),
which was always regarded as its sibling species. The results obtained
indicate M. mongolicus
as a member of Alexandromys
but not of the
Microtus arvalis
group, thus being concordant with the cytogenetic
data. The mitochondrial data support the species status of M. gromovi;
moreover, its placement as a part of a trichotomy with M.
miiddendorffii s.l. and M. mongolicus
contradicts the traditional
affiliation of M.
gromovi with
M. maximowiczii. The divergence rate of
cytb third position transversions in Microtus is
estimated at
approximately 8% per Myr, which corresponds to approximately 30% per
Myr for all substitution types at all codon positions. The maximum
likelihood distance based on complete sequence showed a tendency for a
progressive underestimation of divergence and time for older splits.
According to our molecular clock analysis employing nonlinear
estimation methods, the split between Alexandromys and Pallasiinus and
basal radiation within Alexandromys
date back to approximately 1.2 Mya
and 800 Kya, respectively.
Abstract. New archaic Early Palaeolithic
sites,
Bogatyri/Sinyaya Balka and Rodniki, are reported from the Taman
Peninsula in southern Russia. The geological setting of the sites as
well as the mammal fauna, palynological data, and palaeomagnetic data
clearly indicate mid Early Pleistocene, Early Biharian age of the
deposits. In many of its typological and technological characteristics,
the archaeological assemblages of
Bogatyri/Sinyaya Balka and Rodniki are similar to the Oldowan industry,
although they show specific local features.
Key words: Early Pleistocene, Gelasian, Calabrian, Early Palaeolithic, mammalian fauna, palynology
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