
Giant, Fungus-Like Organism May Be Completely Unknown Branch of Life (livescience.com) 32
New research suggests that Prototaxites, once believed to be a giant fungus, may actually represent an entirely extinct and previously unknown branch of complex life, distinct from fungi, plants, animals, and protists. Live Science reports: The researchers studied the fossilized remains of one Prototaxites species named Prototaxites taiti, found preserved in the Rhynie chert, a sedimentary deposit of exceptionally well-preserved fossils of early land plants and animals in Scotland. This species was much smaller than many other species of Prototaxites, only growing up to a few inches tall, but it is still the largest Prototaxites specimen found in this region. Upon examining the internal structure of the fossilized Prototaxites, the researchers found that its interior was made up of a series of tubes, similar to those within a fungus. But these tubes branched off and reconnected in ways very unlike those seen in modern fungi. "We report that Prototaxites taiti was the largest organism in the Rhynie ecosystem and its anatomy was fundamentally distinct from all known extant or extinct fungi," the researchers wrote in the paper. "We therefore conclude that Prototaxites was not a fungus, and instead propose it is best assigned to a now entirely extinct terrestrial lineage."
True fungi from the same period have also been preserved in the Rhynie chert, enabling the researchers to chemically compare them to Prototaxites. In addition to their unique structural characteristics, the team found that the Prototaxites fossils left completely different chemical signatures to the fungi fossils, indicating that the Prototaxites did not contain chitin, a major building block of fungal cell walls and a hallmark of the fungal kingdom. The Prototaxites fossils instead appeared to contain chemicals similar to lignin, which is found in the wood and bark of plants. "We conclude that the morphology and molecular fingerprint of P. taiti is clearly distinct from that of the fungi and other organism preserved alongside it in the Rhynie chert, and we suggest that it is best considered a member of a previously undescribed, entirely extinct group of eukaryotes," the researchers wrote. The research has been published on the preprint server bioRxiv.
True fungi from the same period have also been preserved in the Rhynie chert, enabling the researchers to chemically compare them to Prototaxites. In addition to their unique structural characteristics, the team found that the Prototaxites fossils left completely different chemical signatures to the fungi fossils, indicating that the Prototaxites did not contain chitin, a major building block of fungal cell walls and a hallmark of the fungal kingdom. The Prototaxites fossils instead appeared to contain chemicals similar to lignin, which is found in the wood and bark of plants. "We conclude that the morphology and molecular fingerprint of P. taiti is clearly distinct from that of the fungi and other organism preserved alongside it in the Rhynie chert, and we suggest that it is best considered a member of a previously undescribed, entirely extinct group of eukaryotes," the researchers wrote. The research has been published on the preprint server bioRxiv.
an entirely extinct and previously unknown branch (Score:2)
Re: "a series of tubes" (Score:1)
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Yeah it was the great grandpa of the internet. Nearly went extinct because it only had 8 bit IP addresses and TCP hadn't even evolved yet.
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The Muslim and Christian God-squad (one god, several religions ; there's an example of efficiency) weren't wrong about there being intelligent design - they just chose to advertise the idea with an example where it doesn't fit.
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The wording of the question would be important. Biggest in mass or area?
The largest organism in the world, according to mass, is the aspen tree whose colonies of clones can grow up to 8 kilometres (5 mi) in size. The largest such colony is Pando, in the Fishlake National Forest in Utah.
A form of flowering plant that far exceeds Pando as the largest organism on Earth in area and potentially also mass, is the giant marine plant, Posidonia australis, living in Shark Bay, Australia. Its length is about 180 km (112 mi) and it covers an area of 200 km2 (77 sq mi). It is also among the oldest known clonal plants.
Another giant marine plant of the genus Posidonia, Posidonia oceanica discovered in the Mediterranean near the Balearic Islands, Spain may be the oldest living organism in the world, with an estimated age of 100,000 years. https://en.wikipedia.org/wiki/... [wikipedia.org]
And this is why (Score:2)
Narrow minded! (Score:2)
may actually represent an entirely extinct?? (Score:2)
"may actually represent an entirely extinct...."
Well, perhaps for exceptionally low values of extinct.
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no brain, post on slashdot
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Drat, I was very anxious to make a joke.
Oh well, at least my ex still laughs at me.
I don't like the way she points though.
Another brick (Score:1)
How many completely unknown branches of life have been burned and bulldozed into obliviojn? Who knows, who cares... as long as the GDP keeps going up.
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If you think that's interesting, you should check out mixostricha darwinii.
It's got multiple layers of that process happening, some of which aren't yet complete.
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My mistake. It should have been
mixotricha paradoxa
(I did a search on the thing I posted and got a result, but didn't read what the result was. Unfortunately, the result didn't even match what I typed in. *thanks, google*.). The "darwinii" came from the name of the termite that it lives in the guts of. The name means "paradoxical mixture of hairs". Those "hairs" are the bacteria that are becoming embedded in the larger bacterium. And there's more than one kind, which is why they were paradoxical. (A
And ... 8! (Score:2)
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Nope. The specimen is a fossil.
Wait a minute ... Protista? (Score:2)
I still catching up here. When I went to school there were only 3 types of eukaryotes. ... protista is "any eukaryotic organism that is not an animal, plant, or fungus. Protists do not form a natural group, or clade, but are a paraphyletic grouping" according to Wikipedia.
So
Doesn't this mean that Prototaxites are just the newest member of the protista group?
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If the thing had survived until today, we would put it will the other non-plant non-animal non-fungus eukaryotes that we already know about. We can find 5 to 20 supergroups within the Eukaryots in "Eukaryotes" on Wikipedia https://en.wikipedia.org/wiki/... [wikipedia.org] or "Tree of life" https://en.wikipedia.org/wiki/... [wikipedia.org] which branched arly out of the original Eukaryote (LECA).
Each of these could be called a kingdom on their own. We just don't do that because we don't feel the need, as each of them them only have a very
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Well, technically, yes, but that's because protista is, according to what you've quoted, the "miscellanous" or "other" tab in the filing cabinet, so you can't exactly deduce anything from it.
Imagine an alien scientist from the planet Tharg getting an Earth specimen and deciding that the lifeform was "other" as it was carbon based, unlike the iron based, potassium based, and hydrogen based life forms they'd found so far, together with the rarer silicon based lifeform that was already classed "Other". That's
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That is one of the ways that a paraphyletic taxon could have been defined in the past, but modern conventions prefer saying nothing to adding organisms to a taxon already known to be paraphyletic. Taxonomists are trying to tidy up the wording of the "tree of life" not make it even more tangled.
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This whole grouping BS is just to make things easier for humans to guess at what features an organism may have based on phylogeny. Nature doesn't give a shit about compliance to that.
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You are quite likely correct in that assumption, but it is an assumption. Be aware, and treat it with the caution to un-tested assumptions.
The sort of test you would need - absent miraculously finding a living derivative of Prototaxites, or even more miraculously finding a large proportion of it's genome in the Rhynie Chert (whose deposition conditions were very unfavourable to preservation of biological molecules - very hot, and very wet), would
Sometimes classifications are arbitrary (Score:2)
When I was a kid, we thought there were three "kingdoms": plants, animals, and protozoa. Now, fungi are considered distinct from plants, in part because they consume oxygen instead of CO2 and don't use photosynthesis. But the characteristics that distinguish fungi from plants, are easily surpassed by distinctions between various types of protozoa. The only thing that really links all of protozoa, is that they are single-celled organisms. They too are divided between those that require oxygen, and those that
Obligatory (Score:1)
boring (Score:2)