'Living fossil' fish species has survived for over 400 million years
09-16-2024

'Living fossil' fish species has survived for over 400 million years

A recent discovery slamming the fish world is drawing us deep into the abyss. The protagonist of our story is an ancient fish called a coelacanth.

If you haven’t heard of them, these large, less-than-attractive fish have been swimming around our planet for over 400 million years. Yet, they still have a few tricks up their fins.

Our adventure starts in the sun-soaked stretches of Western Australia, where an ancient, pristinely preserved new coelacanth species from the Devonian Period was found poking through the sand.

The story weaves between past and present, science and culture, tracing the evolution of coelacanths and the Earth itself.

Coelacanths: A fish out of time

What makes these deep-sea dwellers so fascinating? Today, coelacanths are a rare spectacle observed off the coasts of eastern Africa and Indonesia.

Reaching up to 2 meters (about 6.5 feet), they are known as “lobe-finned” fish. Their fin structure bears an uncanny resemblance to our arm bones.

This particular quirk places them closer to lungfish and backboned animals — frogs, emus, mice (and yes, dear reader, humans too) — than most fish.

Over their 410-million-year tenure, coelacanths have bloomed into more than 175 species worldwide. One of their finer moments of diversification occurred during the Mesozoic Era, the age of dinosaurs.

But as the Cretaceous Period (around 66 million years ago) rolled to a close under the impact of an asteroid, these mighty fish fell off our fossil radar.

In 1938, however, a group of South African fishermen pulled a Lazarus-like marvel from the ocean’s depths — a living, breathing coelacanth.

This resurgence led to their infamous reputation as ‘living fossils’. However, evidence is beginning to challenge this notion.

Birth of Ngamugawi wirngarri

This brings us to our ancient starlet, the newly discovered coelacanth called Ngamugawi wirngarri. This specimen comes from a time of heightened tectonic activity.

These time periods were earth-shaking epochs when the terrestrial plates shifted and carved out new habitats.

Ngamugawi wirngarri, a new coelacanth species, skull bones after they were acid etched out of rock at Museum Victoria, 2009. Credit: Flinders University
Ngamugawi wirngarri, a new coelacanth species, skull bones after they were acid etched out of rock at Museum Victoria, 2009. Credit: Flinders University

Dr. Alice Clement, an evolutionary biologist and paleontologist from Flinders University in Australia, was part of the team that christened the fish in partnership with the Mimbi community.

“Our analyses found that tectonic plate activity had a profound influence on rates of coelacanth evolution,” she revealed.

“New species of coelacanth were more likely to evolve during periods of heightened tectonic activity as new habitats were divided and created.”

Gogo sites and coelacanth fish

Ngamugawi wirngarri lived about 380 million years ago amidst the Devonian Period’s tropical reefs, teeming with more than 50 species of fish.

Today, this region is the rocky Gogo Formation on Gooniyandi Country in the Kimberley region of northern Western Australia.

John Long, a Flinders University Strategic Professor of Palaeontology, sheds light on the importance of the Gogo sites.

“For more than 35 years, we have found several perfectly preserved 3D fish fossils from Gogo sites,” he said, “which have yielded many significant discoveries, including mineralized soft tissues and the origins of complex sexual reproduction in vertebrates,” he explained.

Importance of Ngamugawi wirngarri

The story of coelacanths takes a crucial turn as we dive deeper into their lineage. Many landmarks of human anatomy, such as our jaws, teeth, and chambered hearts, can trace their roots to early fishes in the Early Palaeozoic (540-350 million years ago).

Although coelacanths’ evolution has dramatically slowed since the dinosaur era, they’re not static entities fossilized in time.

Richard Cloutier, a vertebrate paleontologist at the University of Quebec in Rimouski and a study co-author, offers unique insight.

“While most early forms remain poorly known, our study allows us to start understanding how living coelacanth species of Latimeria might not deserve the enigmatic title of ‘living fossils,'” he explained.

The discovery of Ngamugawi wirngarri brings to light the intricate interplay between biology and geology that has shaped life on our planet.

It’s more than just a fish tale — it’s a story about the profound influence of Earth’s ever-changing skin on the dance of evolution.

The study is published in the journal Nature Communications.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. 

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–

News coming your way
The biggest news about our planet delivered to you each day
Subscribe