Metabolic stability of the Pallas' spadefoot Pelobates vespertinus under extreme hypoxia.

The Pallas' spadefoot Pelobates vespertinus is a frog species native to eastern Europe and west Siberia. This species resists harsh winter conditions by moving up to 2 m underground. This amphibian is the first species known to withstand extreme air hypoxia.

Viviparity is associated with larger female size and higher sexual size dimorphism in a reproductively bimodal lizard.

Squamate reptiles are central for studying phenotypic correlates of evolutionary transitions from oviparity to viviparity because these transitions are numerous, with many of them being recent. Several models of life-history theory predict that viviparity is associated with increased female size, and thus more female-biased sexual size dimorphism (SSD). Yet, the corresponding empirical evidence is overall weak and inconsistent.

The Impact of Long-Term Hypoxia on the Antioxidant Defense System in the Siberian Frog Rana amurensis.

The Siberian frog Rana amurensis has a uniquely high tolerance to hypoxia among amphibians, as it is able to withstand several months underwater with almost no oxygen (0.2 mg/liter) vs. several days for other studied species.

Metabolomic Profiling Reveals Differences in Hypoxia Response between Far Eastern and Siberian Frogs.

Anoxia is a significant challenge for most animals, as it can lead to tissue damage and death. Among amphibians, the Siberian frog is the only known species capable of surviving near-zero levels of oxygen in water for a prolonged period. In this study, we aimed to compare metabolomic profiles of the liver, brain, and heart of the Siberian frog exposed to long-term oxygen deprivation (approximately 0.

Biochemical response of two earthworm taxa exposed to freezing.

Several earthworm species are known to be able to withstand freezing. At the biochemical level, this ability is based on cryoprotectant accumulation as well as several other mechanisms. In this study, we used H NMR to investigate metabolomic changes in two freeze-tolerant earthworm taxa, Dendrobaena octaedra and one of the genetic lineages of Eisenia sp.

Metabolomic Analysis Reveals That the Moor Frog Uses Both Glucose and Glycerol as Cryoprotectants.

The moor frog is one of a few amphibians that can tolerate freezing to low temperatures, up to -16 °C. In this study, we performed metabolomic analysis of the liver and hindlimb muscles of frozen and control . We found that the moor frog synthesizes glucose and glycerol in similar concentrations as low molecular weight cryoprotectants.

De novo assembly and analysis of the transcriptome of the Siberian wood frog Rana amurensis.

The Siberian wood frog Rana amurensis Boulenger, 1886 is the most hypoxia-tolerant amphibian. It can survive for several months in an almost complete absence of oxygen. Little is known about the mechanisms of this remarkable resilience, in part because studies of amphibian genomes are impeded by their large size.

Biochemical Response to Freezing in the Siberian Salamander .

The Siberian salamander Dybowski, 1870 is a unique amphibian that is capable to survive long-term freezing at -55 °C. Nothing is known on the biochemical basis of this remarkable freezing tolerance, except for the fact that it uses glycerol as a low molecular weight cryoprotectant. We used H-NMR analysis to study quantitative changes of multiple metabolites in liver and hindlimb muscle of in response to freezing.

Impacts of environmental change on biodiversity and vegetation dynamics in Siberia.

Biological diversity is the basis for, and an indicator of biosphere integrity. Together with climate change, its loss is one of the two most important planetary boundaries. A halt in biodiversity loss is one of the UN Sustainable Development Goals.

Metabolic response of the Siberian wood frog Rana amurensis to extreme hypoxia.

The Siberian wood frog Rana amurensis is a recently discovered example of extreme hypoxia tolerance that is able to survive several months without oxygen. We studied metabolomic profiles of heart and liver of R. amurensis exposed to 17 days of extreme hypoxia.

Cold-Hardiness of the Common Spadefoot Pelobates Fuscus (Pelobatidae, Anura, Amphibia).

Background: Pelobates fuscus is an anuran amphibian that overwinters on land deep in soil, including regions with low sub-zero temperatures. It is not yet known if such behaviour can be explained by low cold-hardiness of the species.

Objective: To measure cold-hardiness of P.

The Siberian wood frog survives for months underwater without oxygen.

Few of the amphibian species that occur in the Subarctic and in mountains are adapted to low sub-zero temperatures; most of these species overwinter underwater. It is believed that the distribution of the species that overwinter underwater can be limited by the low oxygen levels in waterbodies covered with ice. We show that the colonisation of the coldest areas of Northern Asia (to 71°N) by the Siberian wood frog (Rana amurensis) was facilitated by a unique adaptation, the ability to survive extreme hypoxia - and probably anoxia - in waterbodies during overwintering.

The Japanese tree frog (Hyla japonica), one of the most cold-resistant species of amphibians.

The Japanese tree frog, a representative of the Manchurian fauna, is characterized by an outstanding cold resistance among the anuran amphibian species studied so far. Almost 70% of the specimens from the population inhabiting the middle Amur River withstand the cooling down to-30°C; some animals, down to-35°C. This exceeds more than twofold the cold hardiness of the wood frog (Lithobates sylvaticus LeConte, 1825), which has been considered earlier to be the most cold-resistant species.

Extreme negative temperatures and body mass loss in the Siberian salamander (Salamandrella keyserlingii, amphibia, hynobiidae).

Frozen Siberian salamander safely tolerates long (45 days) stay at-35°C. Short-term (3 days) cooling down to-50°C was tolerable for 40% of adult individuals; down to-55°C, for 80% of the underyearlings. Generally, the salamanders lose about 28% of the body mass during the pre-hibernating period (before winter, at temperatures as low as 0°C) and during the process of freezing (as low as-5°C).

Geographic variation of life-history traits in the sand lizard, Lacerta agilis: testing Darwin's fecundity-advantage hypothesis.

The fecundity-advantage hypothesis (FAH) explains larger female size relative to male size as a correlated response to fecundity selection. We explored FAH by investigating geographic variation in female reproductive output and its relation to sexual size dimorphism (SSD) in Lacerta agilis, an oviparous lizard occupying a major part of temperate Eurasia. We analysed how sex-specific body size and SSD are associated with two putative indicators of fecundity selection intensity (clutch size and the slope of the clutch size-female size relationship) and with two climatic variables throughout the species range and across two widespread evolutionary lineages.

Variation of Reproductive Traits and Female Body Size in the Most Widely-Ranging Terrestrial Reptile: Testing the Effects of Reproductive Mode, Lineage, and Climate.

The European common lizard, , is the most widespread terrestrial reptile in the world. It occupies almost the entire Northern Eurasia and includes four viviparous and two oviparous lineages. We analysed how female snout-vent length (SVL), clutch size (CS), hatchling mass (HM), and relative clutch mass (RCM) is associated with the reproductive mode and climate throughout the species range and across the evolutionary lineages within .

Phylogeography and molecular adaptation of Siberian salamander Salamandrella keyserlingii based on mitochondrial DNA variation.

We assessed the phylogeographic pattern of Siberian salamander (Salamandrella keyserlingii, Dybowski, 1870), which appear to be the most northern ectothermic, terrestrial vertebrate in Northern Eurasia, by sequence analysis of a 611-bp fragment of the mitochondrial cytochrome b gene in 159 specimens from different localities (Khabarovsk region, Sakhalin, Yakutia, Magadan region, Chukotka, Kamchatka and others). The data revealed that cytochrome b lineages of S. keyserlingii are divided into haplogroups A, B and C.

[Genetic structure of populations of Schrenck newt (Salamandrella schrenckii) based on mitochondrial DNA cytochrome b variability data].

Data on variability of nucleotide sequences of mitochondrial DNA (mtDNA) cytochrome b gene of Schrenck newt, Salamandrella schrenckii (Strauch, 1870), from populations of Primorie and Khabarovsk regions have been received. By means of phylogenetic analysis, two clusters of haplotypes--'southern' cluster 1 and 'northern' cluster 2, with divegence level between them estimated as 3%-- were revealed. Results of analysis of mtDNA and cytochrome b amino acid variation allow us to assume that development of a modern area of Schrenck newt occurred from the south on the north of Primorie region.