West African Lungfish

The West African lungfish is a large, eel-like freshwater fish native to rivers, lakes and swamps across much of West and Central Africa, notable as one of only a handful of living lungfish species that retain the ability, inherited from ancient fish ancestors, to breathe air using a modified swim bladder that functions much like a primitive lung in addition to gills. This adaptation allows it to survive in oxygen-poor water and, remarkably, to endure the complete drying up of its habitat during the dry season by burrowing into mud and secreting a mucus cocoon around its body, entering a dormant state called aestivation that can last for many months, or in extreme cases even years, until rain returns and the wetland refills. West African lungfish feed on a varied diet of fish, mollusks, crustaceans and insects, using strong jaws with tooth plates capable of crushing hard-shelled prey. As a close living relative of the ancient fish lineage from which land vertebrates are believed to have evolved, the lungfish holds particular scientific interest as a window into a key transitional stage in vertebrate evolutionary history.