Ancestors of land plants revealed

Apr 18, 2011

It was previously thought that land plants evolved from stonewort-like algae. However, new research published in BioMed Central's open access journal BMC Evolutionary Biology shows that the closest relatives to land plants are actually conjugating green algae such as Spirogyra.

Ancestors of green plants began to colonise the land about 500 million years ago and it is generally accepted that they evolved from streptophyte algae (a group of green, fresh water algae). But this group of algae is very diverse and currently ranges from simple, one cell, flagellates to more complex, branching, algae such as stoneworts (Chara).

It was thought that Charales were the closest relatives to because they share (amongst other characteristics) a similar method of fertilisation, oogamy, with a large egg and small swimming sperm. For this sperm is contained within pollen grains. In contrast, another type of streptophytes, the Zygnematales, use conjugation, a method of reproduction where the gametes are of equal size, isogamy, and one or both crawl, amoeba-like, into a fertilization tube where they meet and fuse.

Some phylogenetic analysis had been done previously, on a smaller number of genes, which seemed to support the Charales theory. However, a multinational team, involving researchers in Germany and Canada, analysed in 129 genes from 40 different green plant taxa. This data showed that, despite the differences in reproductive strategy, the closest living relatives to land plants are in fact the Zygnematales.

Dr Becker explained, "It seems that Zygnematales have lost oogamy and their ability to produce sperm and , and instead, possibly due to selection pressure in the absence of free water, use conjugation for reproduction. Investigation of such a large number of genes has shown that, despite their apparent simplicity, Zygnematales have genetic traces of other complex traits also associated with green land plants. Consequently Zygnematales true place as the closest living relative to land plants has been revealed."

Explore further: How hummingbirds evolved to detect sweetness

More information: Origin of land plants: Do conjugating green algae hold the key? Sabina Wodniok, Henner Brinkmann, Gernot Glöckner, Andrew J Heidel, Hervé Philippe, Michael Melkonian and Burkhard Becker, BMC Evolutionary Biology (in press)

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kevinrtrs
1 / 5 (20) Apr 18, 2011
The researchers are on a hiding to nothing. It's going to be very difficult to reconcile the differences between those supposed ancestoral conjugating blue algae and the land plants. They've just overturned the previous thought on it and it won't be long before their own ideas eat the dust.

Evolution - one ancestor for all life forms - is a myth for the simple reason that new information is required to manufacture structural material, create functional structures and then to actually implement the sequences for those functions.
Then there's the tiny little thing called REPAIRs which we shouldn't even begin to consider.
Random mutation and natural selection cannot produce such new information - no matter how evolutionists want to wave hands and shout down simple common sense. This fact is not going away soon. Unless and until evolutionists can show conclusively that random mutations and natural selection can actually produce new life forms, they'll always be using words like "maybe".
kevinrtrs
1 / 5 (20) Apr 18, 2011
Now please leave the speciation story at the door.

What i'm talking about is how a one-cell organism can turn into a horse. Or a bird or human beings. Where does the information come from? How to form blood vessels, skeletons, wings, feathers, hoofs, feet, nails, clotting, immune systems, nerves, skin etc. All these things have different materials, structures and functions. Where does the knowledge to manufacture and use it come from?????
gvgoebel
5 / 5 (8) Apr 18, 2011
Y'know, on reading KevinTRS and a few others around here, I really wish PhysOrg had an ignore list. Even if he had anything interesting to say, it wouldn't be interesting after the 50th time he said it. But at least I can set the filter to "2" and he'll go away.
jmcanoy1860
5 / 5 (8) Apr 18, 2011
I cannot believe kevin is still trolling about. All of the basic information he asks about is out there. Unicellular to multicellular, cell specialization, endosymbiotic etc. His alternative explanation is "magic!!" which goes to show how rigorously he applies his criteria to evidence.
gvgoebel
5 / 5 (6) Apr 18, 2011
I've seen worse trolls than him. It seems to be rooted in a desire for attention: being unable to inspire applause, he settles for jeers instead.
210
1.5 / 5 (4) Apr 18, 2011
Now please leave the speciation story at the door.

What i'm talking about is how a one-cell organism can turn into a horse. Or a bird or human beings. Where does the information come from? How to form blood vessels, skeletons, wings, feathers, hoofs, feet, nails, clotting, immune systems, nerves, skin etc. All these things have different materials, structures and functions. Where does the knowledge to manufacture and use it come from?????


Can you hypothesize?
I too believe more... 'something' is needed NOT just vast amounts of time...a code, some kind of adaptive influence that resides in the fundamental number of codons, genes, needed by any creature to even meet the criterion for being called 'alive.'
since we do NOT know what life IS, how can we be looking in the right place for adaptive evolution?
Your thoughts?
J-n
5 / 5 (8) Apr 18, 2011
So you've got this soup of stuff, that eventually the items come together to make something that reproduces it's self. It keeps making copies of it's self into the billions. During the copying process some of the little bits arent exactly right, which forms what we call mutations, these mutations for the most part cause the reproductions to cease to funtion, or to be inable to make copies. One of the errors though results in something that makes this individual better at coping it's self than the others, maybe it can copy faster? This individual is better suited, in someway, to it's environment, and therefore makes more copies of it's self than the others do. Eventually some of the errors in this new branch is able to do something else that makes IT better, eventually it supplants the forms that came before it.

None of the stuff that is being mentioned is needed for the beginning steps of things becoming complex, things like skeletons, wings feathers, genes, etc they ALL came slowly.
Paljor
4.2 / 5 (5) Apr 18, 2011
just like the bacteria are adapting around the use of our medicine to treat humans and antibiotics
CSharpner
5 / 5 (7) Apr 18, 2011
Kevin doesn't read the responses. He posts blindly then moves on to another article. All of his less than basic questions are answered almost every time he asks them. And then he asks them again as if someone hit "reset" on his brain (all 4KB of it). I'm thinking of making an "Answers for blind and deaf Kevin" blog and every time he asks the same damned question, I'll post a link to the blog with the answer # and I think I'll provide a rolling count of how many times I've had to provide the answer to him.
trekgeek1
5 / 5 (3) Apr 18, 2011


What i'm talking about is how a one-cell organism can turn into a horse. Or a bird or human beings.



Uh-oh, someone didn't get the talk. You see, when two people are horny and the bible says they can't use protection, they have a baby. Or in love, sometimes they're in love too.

Start with N genes. Gene duplication happens and now I have two copies with a total length of 2N. Isn't that new info? If not, suppose the duplication mutates. Now one of my "N's" is now an "M". Now the sequence reads NM and is longer than the original "N", by a factor of two, and unique. That's new info no matter how you slice it.

I know he probably won't read this, but I thought it's worth writing in case somebody stumbles on this article even years from now.

And then he asks them again as if someone hit "reset" on his brain (all 4KB of it).


Bravo.
gvgoebel
not rated yet Apr 18, 2011
And then he asks them again as if someone hit "reset" on his brain (all 4KB of it)


"Powered By ZX-81!"

Boy, that's showing my age. Yes, I remember when a PC with 64 KB of RAM was a big deal. Now 2 GB doesn't seem enough.
Rohitasch
not rated yet Apr 24, 2011
Now please leave the speciation story at the door.

What i'm talking about is how a one-cell organism can turn into a horse. Or a bird or human beings. Where does the information come from? How to form blood vessels, skeletons, wings, feathers, hoofs, feet, nails, clotting, immune systems, nerves, skin etc. All these things have different materials, structures and functions. Where does the knowledge to manufacture and use it come from?????

Huh? Don't you know? Four worms make a man! Also a horse with hoofs an' all.