Ancient bacterial mats may have been key to first mobile animals

May 16, 2011 by Bob Yirka, report

Modern animal-biomat associations from Los Roques. b, Potential Upper Ediacaran and Lower Cambrian associations. Image illustration: Nature Geoscience, doi:10.1038/ngeo1142
( -- Researchers from Canada studying the highly salty coastal lagoons at Los Roques, Venezuela and the microbial mats found at the bottom of the sea there, have discovered that oxygen levels in the mats, at least in the day time, are high enough to support the development of mobile life forms. Led by University of Alberta palaeontologist, Murray Gingras, the team writes in Nature Geoscience, that levels of oxygen on the ocean floor were up to four times as high as that near the surface; high enough to support the development of mobile sea life; which the team believes could explain how early life forms could have evolved in waters with high salt concentrations.

The mats, which the researchers believe are likely similar to the type that evolved in some early lagoons during the Ediacaran Period, some 542 million years ago (the time most agree multicellular animals first began to appear) are comprised of a bottom layer of sulphide-oxidizing bacteria, which is covered by a top layer of , which produces the oxygen through photosynthesis. They found oxygen levels of between 0.25 and 0.45 atm near the mats, compared to 0.10 at or near the surface.

The findings are important because suggests mobile animals first evolved in early salty lagoons that should have been too salty to produce normal plant growth.

Of course there is one hiccup in the theory, and that is the fact that the mats only produce oxygen during the day when the sun is shining; around the mats plunge at night, leaving the lagoons a very inhospitable place. However, at Los Roques, there are some that exist inside the mats that for the most part shut down at night; , if you will, and thus can survive with almost no oxygen when it’s dark. Gingras and his team support the notion that perhaps some early life forms could have done the same, though others are not quite ready to jump on that bandwagon.

Another issue is that the results are based on the notion that the mats that exist today are in fact the same as the mats that existed way back then; a bit of a leap seeing as how there is really no evidence to support such a supposition. Thus, in order for the ideas suggested in this paper to gain credence, evidence of some similarity will have to be found through further research.

Explore further: How plants drove animals to the land

More information: Possible evolution of mobile animals in association with microbial mats, Nature Geoscience (2011) doi:10.1038/ngeo1142

Complex animals first evolved during the Ediacaran period, between 635 and 542 million years ago, when the oceans were just becoming fully oxygenated. In situ fossils of the mobile forms of these animals are associated with microbial sedimentary structures1, 2, 3, and the animal’s trace fossils generally were formed parallel to the surface of the seabed, at or below the sediment–water interface4, 5. This evidence suggests the earliest mobile animals inhabited settings with high microbial populations, and may have mined microbially bound sediments for food resources6, 7, 8. Here we report the association of mobile animals—insect larvae, oligochaetes and burrowing shore crabs—with microbial mats in a modern hypersaline lagoon in Venezuela. The lagoon is characterized by low concentrations of dissolved O2 and pervasive biomats dominated by oxygen-producing cyanobacteria, both analogous to conditions during the Ediacaran. We find that, during the day, O2 levels in the biomats are four times higher than in the overlying water column. We therefore conclude that the animals harvest both food and O2 from the biomats. In doing so, the animals produce horizontal burrows similar to those found in Ediacaran-aged rocks. We suggest that early mobile animals may have evolved in similar environments during the Ediacaran, effectively exploiting oases rich in O2 that formed within low oxygen settings.

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5 / 5 (2) May 16, 2011
"Sea animals were created on day 5. The land animals were created on day 6"

What evident do you have for this argument? We should start thinking outside the box as "Gregor Mendel".
5 / 5 (1) May 16, 2011
3 words for you: Flying Spaghetti Monster. Amen :-P
5 / 5 (4) May 16, 2011
So no proof for this evolutionary spoof, they admit it themselves. Sea animals were created on day 5. The land animals were created on day 6, no "bacterial mats" needed, just the Word of the Lord.

Clever. First you accuse the authors of not supplying proof, then you counter by supplying a 'theory' without proof.

It must really hurt to contradict yourself within the space of 2 sentences and not realize it.
5 / 5 (1) May 17, 2011
Faith works because it has power in itsself, but natural man cannot believe it.

Ah, so you are an unnatural man - that explains a lot. (And I thought god only created natural things...silly me. /sarcasm )

All matter is basically empty space. Some scientists say that everything consists of cosmic strings, like soundwaves.

I think you should really try to read a book on string theory. Just snapping up a few words and thinking you 'know' something about the subject isn't good enough (and certainly convinces no one here). Certainly your naive comparison of strings and sound waves shows it

And in another thread you wanted explanations - not links to outside articles. Yet all you do is link to an outside article (your book of inane sayings AKA Bible).

At the risk of repeating myself:
"It must really hurt to contradict yourself within the space of 2 sentences and not realize it."

Our reality is supported by another invisible reality that is spiritual.

5 / 5 (1) May 18, 2011
Sea animals were created on day 5. The land animals were created on day 6, no "bacterial mats" needed, just the Word of the Lord.
And Man was created after the animals. Except in Genesis two Man was created before the animals. Then there is the little problem that there were mornings and evening and growing plants but the Sun wasn't created till day four. A major logical fail not to mention none of it matches the physical evidence.

A book full of contradictions is cannot be considered divinely revealed truth even if it matched the physical evidence which it doesn't.

Then there all the problems with the nonexistent Great Flood.

5 / 5 (1) May 18, 2011
You are regurgitating a tired old argument against the book of Genesis.
Fully functional flaw in Genesis that I found independently.

There is no discrepancy between Gen 1 and 2. Genesis 2 puts the focus on day 6
There is difference in the order. This is due to them being from two sources. One has Jehovah and the other has Elohim which is the plural form of god.

Now in some translations it may seem like the order of events is different,
In the original Hebrew that is what the order is.

but that is easily solved.
You mean changed to patch a flaw.

Most translations use plusperfect, "had formed"
Which still has the same meaning as the whole thing was in past tense.

Of course there is also the problem that G2 says

Gen 2:5 before any plant of the field was in the earth and before any herb of the field had grown. For the LORD God had not caused it to rain on the earth, and [there was] no man to till the ground
5 / 5 (1) May 18, 2011
Which is a bit of a problem as G1 has Man on day 6.

Gen 2:7 And the LORD God formed man [of] the dust of the ground, and breathed into his nostrils the breath of life; and man became a living being.
Here it is AFTER Day 7. A rather large bit of a discrepancy there.

Gen 2:19 Out of the ground the LORD God formed every beast of the field and every bird of the air, and brought [them] to Adam to see what he would call them. And whatever Adam called each living creature, that [was] its name.
Hmm. Seems the New KJV doesn't agree with you either. Changing to YOUR version with 'had formed' won't change the meaning or the timing. Nor fix Man being created AFTER the SEVENTH day.

Want another go? I can find more errors.

Now what fantasy would you like to use to explain the failed curse on Cain? Marrying, producing children that are followed for many generations and founding a city just doesn't match the curse of wandering for the rest of his life.


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