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.