the other evolutionary explosion

[IndigoChild5559]

Before the Cambrian explosion there was another period of explosive evolution, and for the life of me, I can't remember what it is called. Plants grew in fractals, and animal life often had three point and five point radial symmetry. Can anyone here help me with this?

 

[exchemist]

Before the Cambrian explosion there was another period of explosive evolution, and for the life of me, I can't remember what it is called. Plants grew in fractals, and animal life often had three point and five point radial symmetry. Can anyone here help me with this?

Well, fivefold symmetry is characteristic of echinoderms (e.g. starfish). These I see appeared in the Cambrian. Before the Cambrian was the Ediacaran, in which a lot of strange animals (or plants, nobody can tell with some of them) appeared. Some of those body plans seem to have been abandoned by the time of the Cambrian itself. Is that what you are thinking of? Or do you mean a later radiation, after the Cambrian one?

 

[Polymath257]

Sounds vaguely like the Ediacaran

 

[shunyadragon]

Sounds vaguely like the Ediacaran

Yes, the Ediacaran, from approximately 635 million to 541 million years ago. It began at the Cryptogenian with a glaciation, and ended at the beginning Cambrian with a glaciation event. There as an extinction event at the end of the Ediacaran The larger animals of the Ediacaran disappeared. Ah . . . kind of small, but large for the time. Then the Cambrian explosion occurred.

 

[Audie]

Before the Cambrian explosion there was another period of explosive evolution, and for the life of me, I can't remember what it is called. Plants grew in fractals, and animal life often had three point and five point radial symmetry. Can anyone here help me with this?

I can say there have been many
larger and smaller spurts of rapid diversification.

 

[IndigoChild5559]

Well, fivefold symmetry is characteristic of echinoderms (e.g. starfish). These I see appeared in the Cambrian. Before the Cambrian was the Ediacaran, in which a lot of strange animals (or plants, nobody can tell with some of them) appeared. Some of those body plans seem to have been abandoned by the time of the Cambrian itself. Is that what you are thinking of? Or do you mean a later radiation, after the Cambrian one?

This is before the Cambrian, and is definitely known as the X Explosian. I just can't remember what X is.

 

[exchemist]

This is before the Cambrian, and is definitely known as the X Explosian. I just can't remember what X is.

I think it has to be the Ediacaran, then. But I have never heard this referred to as an "explosion". The term normally used is "radiation", since it is as if a lot of new species radiated outward from a much smaller number of precursors during the period.

In fact the term "explosion" is also rather misleading for the Cambrian radiation too, since this process took place over some 30-50 millon years, i.e. far from all at once, as a word like "explosion" suggests.

(The term "explosion" is however beloved of Old Earth Creationists, who like to suggest, falsely, that it was all at once and hence "problematic" for the theory of evolution, whereas they suggest it was a sudden event, during which these creatures were all "poofed" into existence.)

 

[metis]

Before the Cambrian explosion there was another period of explosive evolution, and for the life of me, I can't remember what it is called.

How about the "Pre-Cambrian Explosion"?

 

[shunyadragon]

The use of the word "explosion" is a layman word like the "Big bang" and needs explanation. It refers to a period of rapid evolution following a catastrophic event such as world glaciation, catastrophic volcanics, or a huge meteor strike. These events create environmental voids open for the diversification of ne species through evolution. Evolution is environmental driven process, and large scale environmental disasters wipe out the larger animals and other life leave the field open for rapid evolution to fill the world with the diversity of life. These events are fairly common in the history of life on earth.

 

[shunyadragon]

How about the "Pre-Cambrian Explosion"?

I do not believe there is a enough evidence for an Ediacaran (Pre-Cambrian) 'Explosion' of rapid diversification and evolution. Ediacaran is the geologic period life originated and diversified. Indirect evidence considers the possibility that when primitive organism first evolved they evolved and spread rapidly in the oceans world wide, and multi celled organism of the Ediacaran followed. The larger organisms of the Ediacaran were mostly wiped out in the glaciation extinction event at the beginning of Cambrian.

 

[shunyadragon]

I do not believe there is a enough evidence for an Ediacaran (Pre-Cambrian) 'Explosion' of rapid diversification and evolution. Ediacaran is the geologic period life originated and diversified. Indirect evidence considers the possibility that when primitive organism first evolved they evolved and spread rapidly in the oceans world wide, and multi celled organism of the Ediacaran followed. The larger organisms of the Ediacaran were mostly wiped out in the glaciation extinction event at the beginning of Cambrian.

It is a recent proposed designation hypothetically about 33 million years before the Ediacaran extinction and the Resulting Cambrian explosion there was the Avalon explosion, which resulting in the appearance and diversification of more complex multicellular animals and plants.

 

[gnostic]

In fact the term "explosion" is also rather misleading for the Cambrian radiation too, since this process took place over some 30-50 millon years, i.e. far from all at once, as a word like "explosion" suggests.

(The term "explosion" is however beloved of Old Earth Creationists, who like to suggest, falsely, that it was all at once and hence "problematic" for the theory of evolution, whereas they suggest it was a sudden event, during which these creatures were all "poofed" into existence.)

Yes, the space of 50 million years for Cambrian "Explosion" didn't happen instantly.

Creationists often misuse this term, either out of ignorance or out of desperate misinformation.

 

[shunyadragon]

Yes, the space of 50 million years for Cambrian "Explosion" didn't happen instantly.

Creationists often misuse this term, either out of ignorance or out of desperate misinformation.

This true. The lay public misconceptions about time in geologic history lead to a misunderstanding of what is an evolutionary 'explosion' of the diversity life. The evolutionary events are in terms of tens of millions of years. Though the world glaciation that precede these events may be in terms of hundreds of thousands of years.

Further research reveals that the glaciation events are likely a significant cause of these evolutionary explosive events by causing an extinction event that results in an environment that is ideal for evolutionary diversification of new species.

The Avalon 'explosions was preceded by the ~580 Ma Gaskiers glaciation event.

 

[exchemist]

This true. The lay public misconceptions about time in geologic history lead to a misunderstanding of what is an evolutionary 'explosion' of the diversity life. The evolutionary events are in terms of tens of millions of years. Though the world glaciation that precede these events may be in terms of hundreds of thousands of years.

Further research reveals that the glaciation events are likely a significant cause of these evolutionary explosive events by causing an extinction event that results in an environment that is ideal for evolutionary diversification of new species.

The Avalon 'explosions was preceded by the ~580 Ma Gaskiers glaciation event.

That's interesting. I wonder if the term @IndigoChild5559 was thinking of was the "Avalon Explosion" rather than "Ediacaran Explosion", though the two seem to amount to the same thing.

But tell me, how is it that glaciation would have triggered the Avalon radiation, seeing that all life at that time was in the oceans?

 

[shunyadragon]

That's interesting. I wonder if the term @IndigoChild5559 was thinking of was the "Avalon Explosion" rather than "Ediacaran Explosion", though the two seem to amount to the same thing.

But tell me, how is it that glaciation would have triggered the Avalon radiation, seeing that all life at that time was in the oceans?

There were a number of world glaciation extinction events in the early history of the earth up to the Permian. First these events were world wide covering most of the oceans. Sea levels dropped significantly and any species dependent on shallow ocean environments were gone. It is likely the larger more complex organisms of the Ediacaran evolved in shallow shelf seas, and were doomed. The chemistry of the seas changed, and it is well documented in the Permian glaciation event it was devastating to all larger species.

 

[IndigoChild5559]

That's interesting. I wonder if the term @IndigoChild5559 was thinking of was the "Avalon Explosion" rather than "Ediacaran Explosion", though the two seem to amount to the same thing.

But tell me, how is it that glaciation would have triggered the Avalon radiation, seeing that all life at that time was in the oceans?

YES YES YES

LOL I remembered it as the atlantis explosion, and of course couldn't rind it when I tried to look it up. Avalon is a port in Atlantis, no?

 

[YoursTrue]

So let me get away from the name of the era for a moment, if possible. Whatever it's called, would you say it was there before animals? How do you figure?

 

[exchemist]

YES YES YES

LOL I remembered it as the atlantis explosion, and of course couldn't rind it when I tried to look it up. Avalon is a port in Atlantis, no?

As far as I'm aware Avalon was a mythical island, in the legend of King Arthur. So not Atlantis but a similarly mythical maritime place, at least.

The Avalon radiation takes its name from the eponymous peninsula in Newfoundland, where a lot of the relevant Ediacaran fossils were found.

 

[shunyadragon]

YES YES YES

LOL I remembered it as the atlantis explosion, and of course couldn't rind it when I tried to look it up. Avalon is a port in Atlantis, no?

No Avalon is not part of Atlantis (?). It is the name of geographic location in Newfoundland where the classic Ediacaran fossils are found documenting the event.

 

[Audie]

So let me get away from the name of the era for a moment, if possible. Whatever it's called, would you say it was there before animals? How do you figure?

Personally I don't understand the question.
Could you rephrsse?