Editing Gar (section)

===Swim bladder===
As their vascularised swim bladders can function as lungs,<ref name="FB" /> most gars surface periodically to take a gulp of air, doing so more frequently in stagnant or warm water when the concentration of oxygen in the water is low. Experiments on the swim bladder has shown that the temperature of the water affects which respiration method the gar will use—aerial or aquatic. They increase the aerial breathing rate (breathing air) as the temperature of the water is increased. Gars can live completely submerged in oxygenated water without access to air and remain healthy while also being able to survive in deoxygenated water if allowed access to air.<ref>{{cite journal|last1=Renfro|first1=Larry|last2=Hill|first2=Loren|title=Factors Influencing the Aerial Breathing and Metabolism of Gars (Lepisosteus)|journal=The Southwestern Naturalist|date=1970|volume=15|issue=1|pages=45–54|jstor=3670201|doi=10.2307/3670201}}</ref> This adaptation can be the result of environmental pressures and behavioral factors.<ref>{{cite journal|last1=Hill|first1=Loren|title=Social Aspects of Aerial Respiration of Young Gars (Lepisosteus)|journal=The Southwestern Naturalist|date=1972|volume=16|issue=3|pages=239–247|jstor=3670060|doi=10.2307/3670060}}</ref> As a result of this organ, they are extremely resilient and able to tolerate conditions that most other fish could not survive.