IMMORTAL

Then in 1938, a museum curator named Marjorie Courtenay-Latimer examined a strange fish caught off the coast of South Africa and realized it matched those “extinct” fossils almost perfectly. It was one of the biggest zoological discoveries of the 20th century.

What makes them especially important is that they’re lobe-finned fish-- their fins are fleshy and supported by bone structures somewhat similar to the early limbs of vertebrates that eventually evolved to walk on land. Watching them swim is apparently eerie because the fins move in an alternating pattern that almost resembles walking.

They’re also ancient in a very literal evolutionary sense. The lineage is over 400 million years old, meaning coelacanth ancestors existed long before dinosaurs did. Modern coelacanths live deep in the ocean, usually hundreds of meters down near volcanic caves, which is probably part of why they escaped notice for so long. They’re nocturnal predators that eat smaller fish and squid, and they can grow over 6 feet long.

And somehow they only get stranger the more you learn about them.

There are actually two known living species--one found near the Comoros Islands and East Africa, and another discovered in Indonesia in the 1990s. Until that second species was identified, people thought the first was the only surviving coelacanth left on Earth.

They live incredibly slowly. They can apparently live for around 60 years or more, don’t reach maturity until their 40s or 50s, and have very low reproduction rates, which makes them especially vulnerable as a species.

Their reproduction is wild too-- they don’t lay eggs externally like many fish. The females keep the eggs inside their bodies, and the babies hatch internally, so the young are born live after an extremely long gestation period that may last over 3 years, which is one of the longest known pregnancies of any fish!!

They also have a unique organ called the rostral organ in their snout that can detect electrical signals in the water, helping them locate prey in dark deep-sea environments where visibility is poor.

And despite looking like they should be enormous apex predators from some primordial nightmare, they’re actually pretty calm and slow-moving most of the time. They conserve energy by drifting in ocean currents and hanging out in underwater lava caves during the day before hunting at night.

One of my favorite details is that they still have a tiny oil-filled structure where ancient lungfish relatives would’ve had a functional lung. It’s basically an evolutionary leftover from ancestors that lived in much shallower waters.

And despite seeming so “primitive,” they’re not unchanged fossils frozen in time, they’ve still been evolving all along. They’re just part of an incredibly old lineage that survived while most related groups disappeared.

Also, scientists were so stunned by the 1938 discovery because finding a living coelacanth was sort of equivalent to discovering a living dinosaur wandering around unnoticed. Entire textbooks had to be reconsidered because this animal had gone from “extinct for tens of millions of years” to “apparently just extremely private.”

Good lord I went on for too long, Sorry!!😅