Explanations for the Cambrian Explosion

In fact, Darwin, in the "Origin of Species" suggested one or several forms as a starting point. He had no reason to know if we are descended from one or from more than one population (thanks to RAZD's note).Since then we have learned a lot (a astronomical understatement) about living forms on Earth. So far all that information says that they are all tied together in a way which suggests that, however many got started, only one lineage has survived through to today.There is a possibility that we are overlooking something somewhere that is a descendant of another lineage but we have no evidence for that.

How is this link helpful? I thought it was supposed to support Genesis. Yet I see no "beasts of the field", I see nothing to be sown into the ground. I see no fish. I see absolutely nothing mentioned in Genesis and I everything I see is missing.

http://gsa.confex.com/...AM/finalprogram/abstract_114319.htmWorked for me.

I just went over the whole thread. I don't see any answers to what you've been told.1. The cambrian "explosion" occurred over a time frame comparable to the time between the KT boundary and today. We know what evolved over that time.2. The various organisms that "suddenly" (see above) appeared would ALL look to the untrained eye like a bunch of slight variation on the "creepy crawly" model. We assign them to different high taxa today but they were not as different from each other as mammals, insects and mollusks are today.3. There isn't a particular dearth of fossils beyond what one expects when you are looking back for over half a billion years.4. There are, as of the last few decades, precursors to the cambrian life so it isn't as "sudden" or "mysterious" as it might have been called 50 years ago.In other words, sem problemas.You haven't show any hint that you have "got" all this yet.Meanwhile since you like to pretend to be interested in learning why don't you start to discuss index fossils?

There is NOT zilch! You have to pay attention when you are told something. For a couple of billion years there was no oxygen in the air. That makes multicellular organisms difficult.Then it took most of another couple of billion to reach about 10 %. Strangely it was just about this that muliticellular life appeared.In addition, some selective pressures are needed. The time of snowball earth is conjectured to have supplied such pressure if competition didn't. Yet.. we do have such evidence. Not a heck of a lot to be sure but it is there.This is not the total mystery you think it is.And if it was; so what? Just what does not knowing the detailed how of something mean?

Please note the Cambrian started 542 mya. That means that there was 38 million years (half the time back to the KT boundary) to get from simpler organisms to what we see early in the Cambrian.You quote says:

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Before about 580 million years ago, most organisms were simple, composed of individual cells occasionally organised into colonies.

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It does NOT support "zilch". It says 'most'. Perhaps there was nothing but that is not what the post says. And it is 38 million years (which is a rather long time) before the Cambrian starts. The oxygen content of the seas was also low. It has to be in equilibrium with the air. The point is that there wasn't oxygen for most of the vast expanse of time before. I didn't make myself clear. It is about this time that multicellular organisms started to appear not the life of the Cambrian. You asked about "why only simple life for so long". This is one thing that may have influenced it. The timing is just at the end of snowball earth so it may be connected. It is only conjecture that they are connected it may simply have been contingency or the level of oxygen in the air was finally adequate at the same time. Of course, it was a long time before the Cambrian. The build up from mostly single (all?) celled organisms began a long time before the Cambrian. It didn't just "poof" at the Cambrian. That is the point. You've now backed up to about 58 million years before the Cambrian.And, of course, the Cambrian itself lasted about 29 million years. (abe- 29 being the smallest range I could find. Other sources suggest 50 million years). That gives you a rather long drawn out "poof" doesn't it? It is plenty of time in fact. In other words it is a simple-minded god-of-the-gaps argument. This has been demonstrated to be poor theology over and over. So much so that sophisticated theologians and other believers know how foolish it is.This gap is already a lot more closed that it was a very few decades ago and it is also a lot more closed than you think it is. Your ignorance of facts doesn't mean they are not there.Edited by NosyNed, : No reason given.

"Most" here can be two different things. Most of those found or actual majority of what lived. You appear to be talking about two different "most"s.

Page not foundThis article discusses the measurement of oxygen levels and the appearance of more complex life forms.

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The sudden appearance of large animals more than 500 million years ago may be due to a huge increase of oxygen in the world's oceans, according to Canadian researchers.

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The research analysed sediments found in 2002 by Narbonne and his research team that contained fossilised 575 million-year-old complex life forms sandwiched between layers of sandstone. Their find pushed back the age of Earth's earliest known complex life to soon after the melting of the "snowball" glaciers of the massive Gaskiers Glaciation 580 million years ago.

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