Weird ‘Living Fossil’ Fish Lives 100 Years, Pregnant For 5

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The coelacanth — an enormous bizarre fish nonetheless round from dinosaur occasions — can reside for 100 years, a brand new examine discovered.

These slow-moving, people-sized fish of the deep, nicknamed a “residing fossil,” are the alternative of the reside quick, die younger mantra. These nocturnal fish develop at an achingly sluggish tempo.

Females don’t hit sexual maturity till their late 50s, the examine stated, whereas male coelacanths are sexually mature at 40 to 69 years. And possibly strangest of all, researchers determine being pregnant within the fish lasts about 5 years.

Coelacanths, which have been round for 400 million years, had been thought extinct till they had been discovered alive in 1938 off South Africa. Scientists lengthy believed coelacanths reside about 20 years. However by making use of a regular approach for relationship business fish, French scientists calculated they really reside near a century, in keeping with a examine in Thursday’s Present Biology.

Coelacanths are so endangered that scientists can solely examine specimens already caught and useless.

Up to now, scientists calculated fish ages by counting huge strains on a selected coelacanth scale. However the French scientists discovered they had been lacking smaller strains that would solely be seen utilizing polarized mild — the approach used to determine the age of business fish.

Research co-author Bruno Ernande, a marine evolutionary ecologist at France’s marine analysis institute, stated polarized mild revealed 5 smaller strains for each huge one. The researchers concluded the smaller strains higher correlated to a 12 months of coelacanth age — and that indicated their oldest specimen was 84 years outdated.

Utilizing the approach, the scientists studied two embryos and calculated the biggest was 5 years outdated and the youngest was 9 years outdated. So, Ernande stated, they figured being pregnant lasts at the very least 5 years in coelacanths, which have reside births.

That five-year gestation is “very unusual” for fish or any animal, stated Scripps Establishment of Oceanography’s Harold Walker, who wasn’t a part of the analysis.

Despite the fact that coelacanths are unrelated genetically and present broad evolutionary variations, they age slowly like different dwellers of the deep, sharks and rays, Ernande stated. “They may have developed comparable life histories as a result of they’re sharing comparable kind habitats,” he stated.

Comply with Seth Borenstein on Twitter at @borenbears.

The Related Press Well being and Science Division receives help from the Howard Hughes Medical Institute’s Division of Science Training. The AP is solely accountable for all content material.



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