
From ScienceDaily:
Ancient alga knew how to survive on land before it left water and evolved into the first plant
Up until now it had been assumed that the alga evolved the capability to source essential nutrients for its survival after it arrived on land by forming a close association with a beneficial fungi called arbuscular mycorrhiza (AM), which still exists today and which helps plant roots obtain nutrients and water from soil in exchange for carbon. The previous discovery of 450 million year old fossilised spores similar to the spores of the AM fungi suggests this fungi would have been present in the environment encountered by the first land plants. Remnants of prehistoric fungi have also been found inside the cells of the oldest plant macro-fossils, reinforcing this idea. However, scientists were not clear how the algal ancestor of land plants could have survived long enough to mediate a quid pro quo arrangement with a fungi. This new finding points to the alga developing this crucial capability while still living in the earth’s oceans!
Dr Delaux and colleagues analysed DNA and RNA of some of the earliest known land plants and green algae and found evidence that their shared algal ancestor living in the Earth’s waters already possessed the set of genes, or symbiotic pathways, it needed to detect and interact with the beneficial AM fungi.
The team of scientists believes this capability was pivotal in enabling the alga to survive out of the water and to colonise the earth. By working with the fungi to find sustenance, the alga was able to buy time to adapt and evolve in a very different and seemingly infertile environment.
Dr Delaux said: “At some point 450 million years ago, alga from the earth’s waters splashed up on to barren land. Somehow it survived and took root, a watershed moment that kick-started the evolution of life on earth. Our discovery shows for the first time that the alga already knew how to survive on land while it was still in the water. Without the development of this pre-adapted capability in alga, the earth could be a very different place today. More.
I wonder if these people realize that their hypothesis, if supported, is an argument for front-loaded evolution, a form of design?
At least, it certainly sounds/reads that way.
Here’s the abstract:
Colonization of land by plants was a major transition on Earth, but the developmental and genetic innovations required for this transition remain unknown. Physiological studies and the fossil record strongly suggest that the ability of the first land plants to form symbiotic associations with beneficial fungi was one of these critical innovations. In angiosperms, genes required for the perception and transduction of diffusible fungal signals for root colonization and for nutrient exchange have been characterized. However, the origin of these genes and their potential correlation with land colonization remain elusive. A comprehensive phylogenetic analysis of 259 transcriptomes and 10 green algal and basal land plant genomes, coupled with the characterization of the evolutionary path leading to the appearance of a key regulator, a calcium- and calmodulin-dependent protein kinase, showed that the symbiotic signaling pathway predated the first land plants. In contrast, downstream genes required for root colonization and their specific expression pattern probably appeared subsequent to the colonization of land. We conclude that the most recent common ancestor of extant land plants and green algae was preadapted for symbiotic associations. Subsequent improvement of this precursor stage in early land plants through rounds of gene duplication led to the acquisition of additional pathways and the ability to form a fully functional arbuscular mycorrhizal symbiosis. (PDF available.) – Pierre-Marc Delaux, Guru V. Radhakrishnan, Dhileepkumar Jayaraman, Jitender Cheema, Mathilde Malbreil, Jeremy D. Volkening, Hiroyuki Sekimoto, Tomoaki Nishiyama, Michael Melkonian, Lisa Pokorny, Carl J. Rothfels, Heike Winter Sederoff, Dennis W. Stevenson, Barbara Surek, Yong Zhang, Michael R. Sussman, Christophe Dunand, Richard J. Morris, Christophe Roux, Gane Ka-Shu Wong, Giles E. D. Oldroyd, Jean-Michel Ané. Algal ancestor of land plants was preadapted for symbiosis. Proceedings of the National Academy of Sciences, 2015; 201515426 DOI: 10.1073/pnas.1515426112
as to this claim:
Maybe in Darwinian imagination it can happen that way, but not in the real world:
Of related note:
Adaptation for the win! Top down design is exactly what we observe.
The algae encountered fungi and formed a symbiotic relationship before either colonized land. After fungi colonized land, the algae could use the “land-fungi” as a crutch to move themselves onto land.
Or
“Algae already possessed genes for land, while in water.”
Yeah the second one has more of a ring to it, but it’s also a good combination of equivocation and bias.
Which is exactly what I’d expect from UD.
as to “a good combination of equivocation and bias.
Which is exactly what I’d expect from UD.”
Like the overt bias witnessed when Darwinists assume that common ancestry is true prior to their analysis of sequences and then assume that their biased analysis of sequences is proof of common ancestry? Even though they have not one shred of empirical evidence that unguided material processes can generate nor fundamentally transform proteins?
Yes I guess that would make Darwinists experts on equivocation and bias! 🙂
“The algae encountered fungi and formed a symbiotic relationship before either colonized land.”
So, fungi also had the “land gene” while living in water, Alicia. Fascinating.
“Which is exactly what I’d expect from UD.”
Actually, that is from the link not UD. And the paper had an exclamation point to boot. Design!
It’s not a bias, BA.
Not when there is mountains of evidence supporting common ancestry.
It’s a fact.
There is nothing to suggest the fungi “had the land gene while living in water.”
Current thinking is that the “land genes” developed from genes that allowed “shallow-water fungi” to tolerate dessication.
And what I said I have come to expect from UD, is “the equivication/bias combination in everything posted.”
Alicia Cartelli:
Nonsense. The concept isn’t testable. There isn’t a mechanism capable of getting beyond populations of prokaryotes and you have to start with populations of prokaryotes.
Endosymbiosis only gets you to prokaryotes with mitochondria/ chloroplasts. At a minimum eukaryotes require a nucleus.
Your “common ancestry” is a non-starter, sweetie.
“Not when there is mountains of evidence supporting common ancestry.”
A single protein cannot even be transformed into another similar protein of a different function by unguided material processes.
Your supposed ‘mountain of evidence’ for common ancestry isn’t even a molehill of evidence.
I didn’t realize you were a leading biologist who got to decide what is and is not a eukaryote, Virgy. The defining characteristic of eukaryotes are membrane-bound organelles. Of course, when eukaryotes first evolved there was no black-and-white difference between prokaryotes and eukaryotes. You simply have no idea what you are talking about.
BA, we can look at thousands of examples, in living species or in the fossil record, all of which support common ancestry.
Either organisms share common ancestry, or your god designed organisms to look like they evolved from common ancestors. But why would he do such a thing?
I’m impressed at your ability to ignore all the evidence behind evolution, evidence that is constantly staring you in the face. I guess when you have no idea what you are talking about though, it’s much easier.
Don’t expect me to respond to either of you again, unless something intelligent comes across the screen.
I won’t hold my breath.
“unless something intelligent comes across the screen.”
What? An atheist actually admits that intelligence is detectable? Heresy I tell you! Call an atheist inquisition. 🙂
AC, contrary to what you imagine to be true, you have ZERO real time empirical evidence that common descent is true.
Besides you not having any real time empirical evidence, both the fossil record and genetic evidence are very antagonistic to your Darwinian claims and are very friendly to Theistic claims.
Not if eukaryotes came first. Or if the two arrived independently. But if Alicia want’s to believe in magic, who are you to say no?
Mungy, sorry but I think you have it backwards.
I’m certainly not person here who believes in “magic.”
“I’m certainly not person here who believes in “magic.””
Actually, as an atheist who believes that undirected random chaos brought the entire universe, and everything in it, into existence, you believe in far more ‘magic’, i.e. miracles, than any Christian Theist ever has. You just don’t believe in the miracle maker:
Although the term “chance” can be defined as a mathematical probability, such as the chance involved in flipping a coin, when Darwinists use the term ‘random chance’, generally it’s substituting for a more precise word such as “cause”, especially when the cause, i.e. ‘mechanism’, is not known. Several people have noted this ‘shell game’ that is played with the word ‘chance’.
Thus to say ‘it happened by chance’, as it is usually used by Darwinists, is in reality a ‘placeholder for ignorance’ instead of being an appeal to a known cause.
Thus, when an atheist states that something happened by chance, we have every right to ask, as Talbott pointed out, “Can you be a little more explicit here?”
Quote, Music, Verse:
Alicia Cartelli:
THE defining characteristic is a membrane-bound nucleus. If you only have the organelles and no nucleus you don’t have a eukaryote. However if you have a nucleus and no organelles you still have a eukaryote.
Of course you don’t have any evidence that eukaryotes evolved. So there isn’t any difference between your version and a cartoon.
It takes extraordinary faith to be an atheist. Even though atheist have ZERO evidence that undirected material processes can produce even a single protein, none-the-less, the atheist still believes, apparently with all his/her heart and soul, that undirected material processes can construct the human brain, made up of trillions upon trillions of precisely placed protein molecules, the result of which is, far, far more complex than the entire internet combined.
The level of blind faith that atheists have in undirected material processes to do such a unbelievable thing simply puts the faith that many Christians have in God to shame.
Of related note to “It’s certainly true that electrical activity in the brain is synchronised over distances that cannot be easily explained”, the following paper and video comments on ‘zero time lag’ in synchronous brain activity:
Back to biology school for you Alicia Cartelli.