The Cambrian Explosion - Part 2 of 2

The Cambrian Explosion. There are two principle options which are invoked in an effort to account for the sudden diversity: (1) the different forms arose at the start of the Cambrian from a single common stock from which the various forms radiated, or (2) the divergence happened much earlier. If they diverged at the beginning of the Cambrian then it does some way to explaining the absence of preceding fossils but then it remains inexplicable how the wide divergence of characteristics occurred so suddenly, i.e. that the various phyla appear so different as to be unrelated. If, on the other hand, they diverged considerably before the Cambrian era (so as to allow for the divergence of various forms, then it is extraordinary that all the various lines should reach a fossilizable stage at much the same time.

One example of a Cambrian-appearing organism is the sponge. There are four classes of sponges, all of which appear abruptly in the Cambrian. Despite a relatively unspecialized structure, the classes are distinct and difficult to relate to one another. There is no sign of intermediary fossils and there is certainly no consensus as to how they could potentially have evolved from a common ancestor. Despite their primitive form, the sponges are quite separate from the rest of the animal kingdom.

Similarly, as far as the arthropods are concerned, the different subphyla of trilobites, horseshoe crabs and crustaceans arise in the Cambrian. Furthermore, the crustaceans are exceedingly diverse. All four major classes of the crustaceans and many lower taxa are found in the Cambrian; but, again, despite this multitude of fossils, no trace can be found of any transitional forms which would link the different groups to a common ancestor.

One attempt to account for the Cambrian explosion involves the proposal that there was a substantial increase in oxygen about this time which stimulated rapid evolutionary progress -- but such a suggestion ignores the sheer improbability of biological macromolecules, whether oxygen is plentiful or not. The enigma is compounded because, not only do different phyla appear suddenly, but also -- within most of the phyla -- very distinct classes arise, again at more or less the same time.

The Cambrian Explosion. In summary, what is generally proposed, is the extraordinary coincidence that these diverse types of organism with their radically different skeletons all reached fossilizable stage within a relatively short period of time. The Cambrian explosion raises the kinds of questions that occur repeatedly regarding the fossil record. First is that major new types of organism appear suddenly and abruptly. Second, many different lines, exhibiting the same sort of significant development, arise about the same time. There exists such a radical diversity that it becomes implausible that they shared a recent common ancestor. It also seems unrealistic that the same sort of advance could have arisen independently in several lines, especially simultaneously.

For more on the Cambrian Explosion, please visit my friends at http://www.ColdwaterMedia.com for more video in the Icons of Evolution series. Also visit http://www.allaboutscience.org/the-cambrian-explosion.htm for more research on issues of science, evolution, design, and origins, including the Cambrian Explosion.

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• Cambrian Explosion
• Fossil Record
• Evolution
• Coldwater
• Darwin
• Species
• Diversity
• Randall Niles
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[Elvikowsky]

As if any serious scientist ever claimed the earth was 100 billion years old. Haha, who told you that? Your claim is simply ridiculous.

[22fr6]

Also, these people forget the Endicaranian. That was where animals began, as very strange weird looking blobs. But once the first traces of any hard shells develop, the blobs can't compete and die. There was no cambrian explosion, simply a development of shells and skeletons.

[peyupsgurl]

@22fr6 I see you are ignoring the evidence just to continue with your belief

[agonyflips]

@FeignofCordor, Atheists have a will not to believe, what?

1st, I'm not an atheist. 2nd, Historically God was the answer for everything, e.g. when the sun darkened during a solar eclipse it was god(s) doing. Yet, with science comes enlightenment & man is better able to explain the world around him (i.e. the moon blocking the sun) & there's less a need to attribute causes to 'Acts of God'.

Watch this video:

cut & paste into URL

watch?v=mE-NQ6mYJsg

Interesting point of view

[FeignofCordor]

@agonyflips

Science also changes over time with new discoveries and Christians have many good reasons to believe in God`s existence however Atheists don`t have equally good reasons to argue against God`s existence only a will to not believe.

[FeignofCordor]

@22fr6

Sorry but the Cambrian Explosion is a scientific fact and there is no pre Cambrian evolutionary explanation for their existence. Even Dawkins says that it can not be explained. So what you said is not accurate.

[agonyflips]

There's a nice little video on the first member of the animal kingdom. The basis for all other animals to come. Search Youtube for '1of6 - The Shape of Life - Episode 01 - Origins' or

or cut and paste the following to a Youtube URL,

watch?v=fwesx8Ko0n8

[agonyflips]

@Seigu007 What faith do you belong to 'cause I can probably cite an example when every faith's God Fearing people did some horrific things & as such should be disavowed.  God seems never to be the problem, it's the religious that are.

-

Creationists arguments which seemed always to be based on the literalness of the bible, seem always to change (e.g. Earth being 6,000 years old--missing link b/n ape & man--Cambrian Explosion? etc.)

Lack of evidence means nothing as you can't prove god exists...

[agonyflips]

The theory of evolution seems to work fine for 520million years.

So there's what, some hiccup before that? Big deal. Every Creationist changes their argument time and time again, and when they first hear about the 'Cambrian Explosion' it's all see, see, I told you, as if they've finally found a winning argument yet again. It's all moot really.

Evolution is about the changes. How life began is a whole different story.

It's sad when people think evolution & god can't coexists. I SMH!

[agonyflips]

I think I'm agnostic but,

I haven't decided.

*RIMSHOT*

[MsMrNoface]

@yahzanhashem Why no Cambrian rabbits?

[Seigu007]

@22fr6 Who’s evidence? Your evidence? Based on what criteria? Yours? That’s a very poor proof to submit.

Your’e a paper tiger and a fool, and a weak one at that.You are scared and it’s sadly telling by tone of your entire tirade.Perhaps you should consider taking a course in logic as well. I certainly would recommend it.