Oxygen hypothesis of polar gigantism not supported by performance of Antarctic pycnogonids in hypoxia.

Can Oxygen Set Thermal Limits in an Insect and Drive Gigantism?

BACKGROUND Thermal limits may arise through a mismatch between oxygen supply and demand in a range of animal taxa. Whilst this oxygen limitation hypothesis is supported by data from a range of marine fish and invertebrates, its generality remains contentious. In particular, it is unclear whether oxygen limitation determines thermal extremes in tracheated arthropods, where oxygen limitation may ...

The effect of 8 weeks of repetitive speed training in hypoxia and normoxia on erythropoietin and aerobic performance of athletes.

Introduction: Due to the changes that exercise brings to the body in hypoxic conditions, today hypoxic exercise is one of the most common types of exercise among most athletes, coaches and sports professionals to improve performance at sea level (1). In this regard, various types of hypoxia exercises, such as speed training in hypoxia, have recently been considered. Hypoxia exercises are usuall...

Effect of different oxygen levels on growth performance, stress response and oxygen consumption in two weight groups of great sturgeon Huso huso

In the present study, different oxygen levels were examined in two weight groups of great sturgeon Huso huso including small size (with initial weight 280.9 ± 49.2 g) and large size (with initial weight 1217.9 ± 138.1 g). The fish were kept in hypoxia (2-3 mg/l), normoxia (5-6 mg/l) and hyperoxia (9-10 mg/l) conditions for 8 weeks and then were individually placed in the tanks with oxygen lev...

Why polar gigantism and Palaeozoic gigantism are not equivalent: effects of oxygen and temperature on the body size of ectotherms

Physiological basis of temperature-dependent biogeography: trade-offs in muscle design and performance in polar ectotherms.

Polar, especially Antarctic, oceans host ectothermic fish and invertebrates characterized by low-to-moderate levels of motor activity; maximum performance is reduced compared with that in warmer habitats. The present review attempts to identify the trade-offs involved in adaptation to cold in the light of progress in the physiology of thermal tolerance. Recent evidence suggests that oxygen limi...