They digitalized a 5 cm-long fetus, the earliest developmental stage available, with synchrotron X-ray at the European Synchrotron ESRF. The data was used to generate detailed 3D models, which allowed the team to analyse how the form of the skull, the brain and the notochord changes from a fetus to an adult. The team also observed how these structures are positioned relative to each other at each stage, and compared their observations with what is known about the formation of the skull in other vertebrates.
Dr Hutel says These are very unique observations, but they represent only a tiny step forward compared to the amount we know on the development of other species. There could be many answers. It is a rare group of bony fishes with fins attached to lobular projections, making them evolutionarily linked to tetrapod ancestors.
Coelacanth was known only as a fossil fish from Devonian. It was an evidence of evolution of tetrapods from such lobe-finned fish like creatures. In , the first living specimen was found and identified as a 'living fossil' in South Africa.
The organism was named Latimeria chalumnae , because of two reasons: 1. Later in s, another species of coelacath were discovered from sea near Indonesia. They are slow evolving organisms, living in deeper parts of Indian ocean.
It was collected in the Comoros Islands in the mids and purchased in by Dr. Schnitzlein, then of the University of Alabama Medical Center, for use in his neuroanatomy studies. After removing the brain, the specimen was donated by Dr. Schnitzlein to the Smithsonian Institution. In the museum acquired Dr. The specimen is identified as Latimeria chalumnae.
Discovering the Coelacanth by Sally M. Walker, Carolrhoda Books, Inc. Skip to main content. Credit: Don Hurlbert. Coelacanth Latimeria. Division of Fishes. Left: A close-up of the fleshy, limb-like pectoral fin of an adult coelacanth. Right: A close-up of the snout of an Indonesian coelacanth.
Note the pores leading into the internal rostral organ, a feature unique to the coelacanth. Sandra J. Raredon and Mark V. This adaptation apparently allows them to open their mouths wider than they would be able to otherwise, improving their predation ability. Coelacanths reproduce via internal fertilization and give birth to relatively well-developed live young.
As soon as they are born, juvenile coelacanths do not receive any further parental care and are ready to begin a predatory lifestyle.
As a result of its small geographic range, low natural numbers, and vulnerability to newly arising deep-sea fisheries, the coelacanth is considered to be critically endangered very highly vulnerable to extinction by marine scientists.
Only a relatively small number of specimens have ever been collected or observed, and without careful management of human activities throughout its range, this species could easily be lost. Given the fact that it has survived for millions of years, the loss of this species as a result of human activity would represent a shameful loss of natural heritage.
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