Why was there a gap of 70 million years in the coelacanths fossil record think about the process of fossilization and where coelacanths are found?

CQ#3: The youngest coelacanth fossil found has been dated to 70 million years ago. Why was there a gap of 70 million years in the coelacanth’s fossil record? A: Coelacanths became extinct 70 million years ago, and then re-evolved.

Why was there a gap of millions years in the coelacanth’s fossil record?

It was Louis Agassiz who first described the group in 1839. Paleontologists had found dozens of different coelacanth species since then, but always in rocks older than 70 million years. The lack of coelacanth fossils in younger strata led them to conclude that coelacanths had gone extinct a long time ago.

Why were there gaps in the fossil record?

The fossil record contains many ‘gaps’. This is because scientist haven’t yet uncovered any form of evidence which indicates the existence of organisms at those points in time.

Why is the evolution of the coelacanth so slow?

Slow to change It is impossible to say for sure, but the slow rate of coelacanth evolution could be due to a lack of natural-selection pressure, Lindblad-Toh says. Modern coelacanths, like their ancestors, “live far down in the ocean, where life is pretty stable”, she says.

Are coelacanth still alive?

Coelacanths reside at ocean depths of as much as half a mile (800 meters). The two extant species, both endangered, are the African coelacanth, found mainly near the Comoro Islands off the continent’s east coast, and the Indonesian coelacanth.

Why did the coelacanth go extinct?

The coelacanth, an elusive deep-sea dwelling fish once thought extinct, has an obsolete lung lurking in its abdomen, scientists have discovered. The lung was likely rendered defunct by evolution as the fish moved into deep water, the international team of researchers report in the journal Nature Communications.

Why are some fossils missing?

The fossil record, however, is quite incomplete. Here’s one major reason why: Sediment has to cover an organism’s remains in order for the long fossilization process to begin. Most organisms decompose before this can happen. Plus, fossils may be set in stone, but they’re far from impervious.

What are gaps in the fossil record called?

Romer’s Gap These gaps represent periods from which no relevant fossils have been found. Romer’s gap is named after paleontologist Alfred Romer, who first recognized it.

What is the gap in the fossil record?

There are three varieties of gaps commonly found in the fossil record. Real gaps are those which cannot be filled. They may result from non-deposition, non-preservation, metamorphism or erosion. The other varieties of gaps are both artificial.

Why the coelacanth is important to the fossil record?

Coelacanths are known as “living fossils,” as they show remarkable morphological resemblance to the fossil record and belong to the most primitive lineage of living Sarcopterygii (lobe-finned fishes and tetrapods). Coelacanths may be key to elucidating the tempo and mode of evolution from fish to tetrapods.

Why are coelacanths special?

Unique to any other living animal, the coelacanth has an intracranial joint, a hinge in its skull that allows it to open its mouth extremely wide to consume large prey. 5. Instead of a backbone, they have a notochord. Coelacanths retain an oil-filled notochord, a hollow, pressurized tube that serves as a backbone.

What does coelacanth taste like?

They don’t taste good. People, and most likely other fish-eating animals, don’t eat coelacanths because their flesh has high amounts of oil, urea, wax esters, and other compounds that give them a foul flavor and can cause sickness.