The World's Oldest "Living Fossil" Is Shaking Up Conventional Evolutionary Theories

Scitech Daily ^ | September 12, 2024 | Flinders University

[SunkenCiv]

Today, the coelacanth is a fascinating deep-sea fish that lives off the coasts of eastern Africa and Indonesia and can reach up to 2m in length. They are "lobe-finned" fish, which means they have robust bones in their fins not too dissimilar to the bones in our own arms, and are thus considered to be more closely related to lungfish and tetrapods (the back-boned animals with arms and legs such as frogs, emus, and mice) than most other fishes.

Over the past 410 million years, more than more than 175 species of coelacanths have been discovered across the globe. During the Mesozoic Era, the age of dinosaurs, and coelacanths diversified significantly, with some species developing unusual body shapes. However, at the end of the Cretaceous Period, around 66 million years ago, they mysteriously disappeared from the fossil record.

The end-Cretaceous extinction, sparked by the impact from a massive asteroid, wiped out approximately 75% of all life on Earth, including all of the non-avian (bird-like) dinosaurs. Thus, it was presumed that the coelacanth fishes had been swept up as a casualty of the same mass extinction event.

But in 1938, people fishing off South Africa pulled up a large mysterious-looking fish from the ocean depths, with the 'lazarus' fish going on to gain cult status in the world of biological evolution.

[SunkenCiv]

There are plant species that have, uh, ginkgo (maidenhair tree), and sago palm ( https://en.wikipedia.org/wiki/Cycas ) which were popular as house plants in Victorian times (if memory serves they’re not too fussy about temp swings and light levels).

[blam]

When I was a kid we had a set of encyclopedias that had a whole page dedicated to a $100,000 reward for one of these fish. Of course, since then they have caught/found numerous.

I was fascinated by that reward

[SunkenCiv]

:^) That’s one reason encyclopedias were expensive back then. :^)

[EinNYC]

They have never been able to keep one alive for long after being brought up in a net, and kept for study.

That is because there is a large difference in water pressure where they live and the surface. They cannot live in the lower pressure water.