Discovery of a warm blooded fish “Opah”

Date: May 16, 2015

Warm blooded Hot blooded Opah fish

Discovery of a warm blooded fish “Opah”

Hot and Warm blooded animals:

Those animals which have capability to maintain a constant body temperature in all conditions are referred to as hot blooded animals (Homeotherms or Endotherms). Whereas those animals which regulate their internal body temperature with respect to the external environment are referred to as warm blooded animals (Poikilotherms or Ectotherms).

Illustrated examples:

Human beings are hot blooded animals. Internal temperature remains constant whether a person is in zero degree or in a hot desert. This heat regulation is attained by a process called homeostasis. Dogs can be seen with an open mouth, salivating. With this in hot days, dogs tend to loose water and maintain a constant body temperature.

Mostly, crocodiles can be seen bathing in sun, with wide open mouth. They actually are capturing solar heat and thus are increasing their body temperature. In cold weather, most of the reptiles (ex. Lizards) become very less active as their body temperatures declines with decreasing external temperature and thus have to hibernate.

Body temperature in fishes:

Fishes are termed as poikilotherms (poikilos=variation; therm=heat). Thus fishes hibernate between hot and cold streams with seasonal variations.


First warm blooded fish: Opah fish

It is discovered by scientists at the US National Oceanic and Atmospheric Administration (NOAA).

Opah or moonfish has ability to circulate heated blood throughout its body which makes it first fish known to be fully warm-blood.

Being a warm-blooded fish it has distinct advantages such as faster swimming speeds and reaction times, better brain and eye function and withstand the effects of cold on vital organs compared to cold-bodied fish