Acute exposure to low oxygen (hypoxia) places conflicting demands on the heart. Whilst an
increase in heart rate (tachycardia) may compensate systemic oxygen delivery as arterial …

A swimbladder is a special organ present in several orders of Actinopterygians. As a gas‐
filled cavity it contributes to a reduction in overall density, but on descend from the water …

Adaptation to extreme environments often involves the evolution of dramatic physiological
changes. To better understand how organisms evolve these complex phenotypic changes …

Previously, we showed that the evolution of high acuity vision in fishes was directly
associated with their unique pH-sensitive hemoglobins that allow O2 to be delivered to the …

In hypoxia, air-breathing fish obtain O2 from the air but continue to excrete CO2 into the
water. Consequently, it is believed that some O2 obtained by air-breathing is lost at the gills …

Amphibious and aquatic air-breathing fishes both exchange respiratory gasses with the
atmosphere, but these fishes differ in physiology, ecology, and possibly evolutionary origins …

Amphibiousness in fishes spans the actinopterygian tree from the earliest to the most
recently derived species. The land environment requires locomotor force production different …

This review explores the long‐standing question:'Why do cardiovascular shunts occur?'An
historical perspective is provided on previous research into cardiac shunts in vertebrates …

In the pirarucu (Arapaima gigas), gill surface area and thus gas exchange capacity of the
gills are reduced with proceeding development. It, therefore, is expected that A. gigas …

The evolutionary origins of specialized organs pose significant challenges for empirical
studies, as most such organs evolved millions of years ago. The Northern snakehead …