Like its modern-day descendants, an ancient big fish known as a coelacanth had gills, but it also sported a well-developed lung, according to a new study. An examination of present-day coelacanths shows that they develop lungs as embryos, but the organ soon becomes vestigial, an adaption that allows the fish to live in deep water and breathe solely with the gills. [Read the full story on the coelacanths]

Creatures' features in 3D

This image shows 3D reconstructions of the pulmonary complex of one species of coelacanth (Latimeria chalumnae) at different ontogenetic stages. (Credit: Brito et al. Nature Communications.)


An unexpected find

Evidence of lung anatomy in L. chalumnae. An internal view of the esophageal wall showing an opening between the esophagus and the lung in L. chalumnae (A); a dissected adult lung (B); a microscopic view of a thin slice of the vestigial lung tissue (C). The scale bar equals 0.2 inches (0.5 centimeters). (Credit: Brito et al. Nature Communications.)


An odd fish

At 427 feet (130 meters) underwater, off Sodwana Bay in South Africa, the extant coelacanth L. chalumnae swims in its natural environment. (Credit: Laurent Ballesta / Andromede Oceanology Ltd / http://www.blancpain-ocean-commitment.com/en-us#!/home.)


Extant, not extinct

The extant coelacanth in its natural environment. (Credit: Laurent Ballesta / Andromede Oceanology Ltd / http://www.blancpain-ocean-commitment.com/en-us#!/home.)


A coelacanth specimen

An adult specimen of the extant coelacanth after dissection. The specimen is kept in the Collection of Comparative Anatomy of the Muséum national d’Histoire naturelle in Paris, France. (Credit: Cupello personal archive/ Muséum national d'Histoire naturelle, Paris.)


They were hooked

An international team of scientists studied the new fossil. Here, the researchers are pictured outside the Platform AST-RX of the Muséum national d’Histoire naturelle in Paris. (Credit: Cupello personal archive/ Muséum national d'Histoire naturelle, Paris.) 


A view into the past

Study co-researcher Paulo Brito created a giant replica of the fossil Coelacanth Mawsonia. (Credit: Didier Dutheil personal archive/ Muséum national d'Histoire naturelle, Paris.)

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