Are they fossils of Ediacaran metazoa?

I think I've spent too much time in the creationist mines. Seeing a civil, fact filled, discussion trying to ascertain a consensus based on the science was a pleasing surprise - when in fact it is the real standard that should be followed.

The personal attack filled screeds and fact obscuring/ignoring are the true outliers.

The personal attack filled screeds and fact obscuring/ignoring are the true outliers.

Sponges and Corals are not metazoa and they are multi-celled animals (I apologize I over react to wrong definitions you were probably just simplifying it I guess).

William said: Sponges and Corals are not metazoa and they are multi-celled animals (I apologize I over react to wrong definitions you were probably just simplifying it I guess).

Stanton said: Actually, coral and other cnidarians are (eu)metazoans, what with them displaying organized tissue systems and (radial) symmetry.

And of course, sponges have a side job of helping people with housework.

Oh, I almost hate to bring up the old Steve Wright joke: "You know, sponges grow on the bottom of the ocean ... did you ever wonder how much deeper it would be if they didn't?"

The TOL web page http://tolweb.org/Animals/2374 uses "metazoa" as a synonym for "animal". Is there some disagreement on that?

Henry J said: The TOL web page http://tolweb.org/Animals/2374 uses "metazoa" as a synonym for "animal". Is there some disagreement on that?

Stanton said: I guess plain-old "metazoa" is to distinguish true animals from animal-like protists, or "protozoa."

William said: Sponges and Corals are not metazoa and they are multi-celled animals (I apologize I over react to wrong definitions you were probably just simplifying it I guess).

Oops. Henry beat me to it: Read all the comments, RBH!

Joe Felsenstein said:

Stanton said: I guess plain-old "metazoa" is to distinguish true animals from animal-like protists, or "protozoa."

Come to think of it, “metazoa” sounds to me like it refers to an intermediate level of organization. Where do we look to find the next level up, say “Euzoa”?

Stanton said:

Joe Felsenstein said: Come to think of it, “metazoa” sounds to me like it refers to an intermediate level of organization. Where do we look to find the next level up, say “Euzoa”?

Eumetazoa is split up into ... [snip good information that is not relevant to my wise-ass comment] According to what I read on Wikipedia, the division of Protostomia into superphyla is rather contentious.

Joe Felsenstein said: Yeah, but those are all mere Metazoans. The name clearly implies there is more, and better! Where do we find them, and what do we call them? ;-)

Nah, "butterzoa" would have to refer to things like cows or goats.

Henry J said: Nah, "butterzoa" would have to refer to things like cows or goats.

Wikipedia: Meta- (from Greek: μετά = "after", "beyond", "with", "adjacent", "self"), is a prefix used in English (and other Greek-owing languages) to indicate a concept which is an abstraction from another concept, used to complete or add to the latter.

Meta is the middle of ortho , meta, para.
I know orthodox. and paradox,but what is the meaning of metadox?

Old Ari said: Meta is the middle of ortho , meta, para. I know orthodox. and paradox,but what is the meaning of metadox?

From the older thread this creationist would point out a problem.
First these fossils are from a single event in geology. The flood event.
There was no glacial action during these events. no snowball earth.
They only can claim glaciers based on simply scratchings in the rock.
Yet in geomorphology these creations are better explained as from water carrying debris.
no need to invoke glaciers. Thats a old wrong idea.
Keep up with the times boys.

Robert Byers said: From the older thread this creationist would point out a problem. First these fossils are from a single event in geology. The flood event. There was no glacial action during these events. no snowball earth. They only can claim glaciers based on simply scratchings in the rock. Yet in geomorphology these creations are better explained as from water carrying debris. no need to invoke glaciers. Thats a old wrong idea. Keep up with the times boys.

mrg said: Oh, I almost hate to bring up the old Steve Wright joke: "You know, sponges grow on the bottom of the ocean ... did you ever wonder how much deeper it would be if they didn't?"

Robert Byers said: *SNIP*

A pretty strong argument seems to have been made, albeit in a blog posting, that these fossils are not definitively Ediacaran metazoans. If both the age and the morphology of the fossils argue at least moderately against that, the best we can say is that we certainly can't be confident that they are.

We are lucky to have any Ediacaran fossils at all.

Still, it is too bad that we will (presumably) never have any molecular genetic data about multicellular life forms from the Ediacaran. That might provide some fascinating insights into early multicellularity, the genetics of morphology, and so on. (With the caveat that current major, well-funded molecular, biochemical, and genetic studies tend to be very human- and mammal-centric, with a supporting role played by Drosophila, E. coli, Saccharomyces cerivisiae and some well-studied pathogens. Other than Drosophila, which was chosen early in the scientific era for convenience, all of the other non-mammalian models are microbes with some kind of a relationship to humans. Major food crops also get a fair amount of study, although agricultural research is less well-funded than biomedical research.)

Also, of course, Ediacarans are only the oldest multicellular forms known from preserved morphology. As I have seen pointed out in comments about both paleontology and archaeology, assuming that the oldest known example of something is necessarily the true oldest example is illogical. On the other hand, that doesn't mean that markedly different ages for a well described phenomenon are likely to occur, either.

Dave Lovell said: ... perhaps they were God's answer to the problem of getting rid of the excess water.