Living Fossils Offer Fundamental Demonstration of Evolutionary Process [Study]

Biological mechanisms play a major role in the evolution of "living fossils." These living organisms have minimal physical variation from ancient forebears and minimal species diversity.

Evolution Plays a Role in Bizarre 'Living Fossil' Fish

A new study showcased the first conclusive proof that a biological mechanism can account for the status of an extinct family of pointy-nosed fish known as gars.

Darwin coined the phrase 1859 because certain living things exhibit remarkably little species diversity and morphological variation from their ancient predecessors. However, there has never been conclusive proof of a mechanism behind living fossils.

Evolutionary researcher Chase Brownstein of Yale University stated that their paper demonstrates that living fossils aren't simply strange accidents of history but offer essential evidence of the evolutionary process in nature.

It not only advances our knowledge of the world's biodiversity but also has the potential to advance human health through medical research.

Despite the fact that 105 million years have passed since their last common ancestor, Brownstein and colleagues from the US and China discovered that two distinct species—longnose gars (Lepisosteus osseus) and alligator gars (Atractosteus spatula)-can generate successful hybrid offspring.

Gars have the slowest rates of molecular evolution of all jawed vertebrate species, according to an examination of 1,105 coding areas of DNA in 481 species. This finding may help explain why their hybrids can still be viable and productive despite evolving into different species for 100 million years.

The evolution of new species may also be hindered when genetic changes occur at a rate that allows hybridization between even highly disparate species.

"We show that gars' slow rate of molecular evolution has stymied their rate of speciation," said Yale University ichthyologist Thomas Near.

"Fundamentally, this is the first instance where science is showing that a lineage, through an intrinsic aspect of its biology, fits the criteria of living fossils."

251-pound Monster Gar Could Be the World's Best Alligator Gar

A Texas fishing guide claims that an enormous alligator gar captured there might surpass the previous record for its kind. On April 16, 2023, in the Trinity River near Huntsville, Texas, anglers Kirk Kirkland and Art Weston of Kentucky hooked the monster, weighing 251 pounds. Kirkland refers to himself as the "world's best alligator gar guide." He holds over 100 world records for the International Game Fish Association (IGFA).

Kirkland called the fish an "absolute monster" in a social media post and shared multiple photos of the alligator gar, one of which showed a scale indicating 251 pounds.

Weston claimed to Field & Stream that he battled the alligator gar for twenty-five minutes after using carp as bait. He acknowledged that because of the gar's power, they had initially thought it to be a genuine alligator.

Another 7-foot alligator gar was caught in Alabama. Keith Dees and his son Huntley were fishing in the Mobile-Tensaw Delta a few days after Thanksgiving when they snagged the largest alligator gar in the state.

They captured a 7-foot-tall alligator gar that weighed 165 pounds on one scale and 175 pounds on another. According to Dees, the state record was 151 pounds.

The fish stayed alive and was weighed at Orange Beach Marina. It broke the state record with an official weight of 162 pounds.

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