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Among seven species of the order Eulipotyphla (from southern Gansu and northern Sichuan Provinces, Central China) studied cytogenetically, karyotypes of one talpid species, Uropsilus aff. soricipes (2n = 36, NFa = 54), and three soricid species, Chodsigoa hypsibia (2n = 65, NFa = 66), Sorex cansulus (2n = 42, NFa = 64) and Sorex thibetanus (2n = 42, NFa = 60), are described cytogenetically for the first time. All four species are endemic to China with distribution ranges restricted to the Qinghai-Tibet Plateau and adjacent mountain ranges. The Ch. hypsibia karyotype consists of mostly acrocentric autosomes and one metacentric pair of autosomes; besides, a B chromosome was identified. No polymorphism was detected among karyotypes of other species, including shrews Sorex bedfordiae (2n = 26, NFa = 44), Anourosorex squamipes (2n = 48, NFa = 92) and Crocidura suaveolens (2n = 40, NFa = 44). The Chinese shrew mole U. aff. soricipes and three shrew species (S. bedfordiae, Ch. hypsibia and A. squamipes) represent autochthonous fauna of Central/Western China, whereas S. thibetanus, S. cansulus and C. suaveolens belong to phylogenetic groups occurring mostly to the north and west from China; therefore, they should be considered relatively recent colonisers. Thus, considering the relationships of the species within phylogenetic groups, our results on karyotypes are in good agreement with molecular genetic data.

Shrews occupy the lower extreme of the seven orders of magnitude mammals range in size. Their hearts are large relative to body weight and heart rate can exceed a thousand beats a minute. To investigate whether cardiac traits that are typical mammalian scale to these extremes, we assessed the heart of three species of shrew (genusSorex) following the sequential segmental analysis developed for human hearts. Using micro-computed tomography we describe the overall structure and find, in agreement with previous studies, a large and elongate ventricle. The atrial and ventricular septums and the atrioventricular and arterial valves are typically mammalian. The ventricular walls comprise mostly compact myocardium and especially the right ventricle has few trabeculations on the luminal side. A developmental process of compaction is thought to reduce trabeculations in mammals, but in embryonic shrews the volume of trabeculations increase for every gestational stage, only slower than the compact volume. By expression of Hcn4, we identify a sinus node and an atrioventricular conduction axis which is continuous with the ventricular septal crest. Outstanding traits include pulmonary venous sleeve myocardium that reaches farther into the lungs than in any other mammals. Typical proportions of coronary arteries-to-aorta do not scale and the shrew coronary arteries are proportionally enormous, presumably to avoid the high resistance to blood flow of narrow vessels. In conclusion, most cardiac traits do scale to the miniscule shrews. The shrew heart, nevertheless, stands out by its relative size, elongation, proportionally large coronary vessels, and extent of pulmonary venous myocardium.

Adrenal glands are the major organs releasing catecholamines and regulating our stress response. The mechanisms balancing generation of adrenergic chromaffin cells and protecting against neuroblastoma tumors are still enigmatic. Here we revealed that serotonin (5HT) controls the numbers of chromaffin cells by acting upon their immediate progenitor “bridge” cells via 5-hydroxytryptamine receptor 3A (HTR3A), and the aggressive HTR3Ahigh human neuroblastoma cell lines reduce proliferation in response to HTR3A-specific agonists. In embryos (in vivo), the physiological increase of 5HT caused a prolongation of the cell cycle in “bridge” progenitors leading to a smaller chromaffin population and changing the balance of hormones and behavioral patterns in adulthood. These behavioral effects and smaller adrenals were mirrored in the progeny of pregnant female mice subjected to experimental stress, suggesting a maternal-fetal link that controls developmental adaptations. Finally, these results corresponded to a size-distribution of adrenals found in wild rodents with different coping strategies.

First data on morphological and mitochondrial variation in the long-tailed hamster Cricetulus longicaudatus is presented. In contrast to genetically monomorphic populations of Mongolia and Tuva, the northeastern part of the Qinghai-Tibetian Plateau was found to harbor several divergent mtDNA lineages. This pattern suggests a recent expansion of the long-tailed hamster to the northern part of its recent range, which started from Tibet, presumably, in the late Middle Pleistocene. Several populations from the northern edge of the species range were found to be morphologically but not genetically distinct. The apparent disagreement between genetic and morphological data can be explained by rapid morphological evolution in peripheral isolates.

Thirty-year studies of populations of eight shrew species in the Middle Yenisei taiga have shown that at the late 20th century the population dynamics had a pronounced cyclic character, but in the 21st century cyclic dynamics changed with fluctuating one. The analysis of the dependence of the animal body weight on the population density have revealed that under cyclic dynamics at the peaks of the population, the animal’s body weight is significantly higher than that at population decline, i.e., the corollary from the Chitty hypothesis (the Chitty effect) is observed. In populations with fluctuating dynamics such regularity has not been observed.

Genetic diversity of the genus Blarinella was studied using one mitochondrial and four nuclear genes as examples. The first genotyping of shrews from the southeast of Gansu province (China), which is a typical habitat of B. griselda, has been performed. Molecular genetic analysis showed that Blarinella sp. from southern Gansu stand apart among the other representatives of the genus and can be assigned to neither of the known species.

In Western Siberia, most boundaries between common shrew chromosomal races have been found to pass along the banks of rivers, mainly those flowing in the meridional direction. The races Serov and Novosibirsk co-inhabited the right bank of the Irtysh. The easternmost point of the Novosibirsk race has been found on the middle Yenisei River, while the race Tomsk in this area was only on the right (eastern) bank.

The results of the first molecular study focused on the phylogenetic position of the Gansu mole, Scapanulus oweni are presented. The analysis based on sequences of the mitochondrial cytb gene and five nuclear genes supports the monophyly of the Scalopini tribe including S. oweni and shows that two highly fossorial talpid tribes, Talpini and Scalopini, are not immediate sister taxa. These results highlight the role of morphological parallelism as a potential source of conflict between molecular and morphology-based phylogenies in Talpidae.

Sequences (MRS) distantly related to mouse mammary tumor virus (MMTV) were found in genomes of a wide range of mammalian species using blot hybridization. The number of MRS copies and the degree of their homology with the hybridization probe varied and did not correlate with the taxonomic position of the species. Nevertheless, within a genus the set of MRS was species specific and reflected the taxonomic relation between the species. MRS were also found in avian genomes and the degree of their homology did not correlate with the taxonomic position of the species either. The origin and distribution of MRS is discussed on the basis of the authors' and published data.