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Billion-year-old fossils may be early fungus



  Picture a ball on a stalk.

When did the first complex multicellular life appear? Most people, being selfish, point to Ediacaran and Cambrian, when the first animal life appeared and then varied. However, studying DNA indicates that fungi can be derived earlier than animals.

However, when it comes to a fossil record, however, things are slightly sparse. There is no clear evidence of a fungus that appears in fossils until Cambrian is complete. Some things from earlier may seem fungus-like, but the evidence is limited to their appearance. Fungi may appear at the time suggested by the DNA but complex, multicellular structures do not change over time. Alternatively, fossils may be correct, and there is something not about DNA data. Or, finally, we may not find enough fossils enough.

A new role right now Nature fully refers to the last option. In this case, a small team of researchers describes the fossils of what looks like fungi that can be up to a billion years old. And the researchers backed up the appearance of a chemical analysis.

Really, really old

The fossils originate in a northern northern Canada, Arctic coast. The fossils themselves are discovered by digesting minerals that contain them as acid. Without the stones, a large collection of tiny fossils float free of charge.

In view of this, these microfossils are like a slightly shrunk balloon with a stem on its base. The stalks are connected to a long tube that can link up multiple wells-like structures. It looks like a lot like some modern fungi, where the well-like structure is a source of spores while the tubes are how the organism grows and spreads within a surface. A critical feature shared with fungi is the fact that the stem is attached to the globe in the remaining branches of the organism at the right angle. The structure contains the name of the new genus, Ourasphaira for the tail and globe; The full name of the species is Ourasphaira giraldae .

  An arrow showing the branches of the right angle of the hollow tube system formed by the early fungus. "src =" https://cdn.arstechnica.net/ wp-content / uploads / 201[ads1]9/05 / Screen-Shot-2019-05-22-at-5.15.38-PM-640x543.png "width =" 640 "height =" 543 "srcset =" https: // cdn .arstechnica.net / wp-content / upload / 2019/05 / Screen-Shot-2019-05-22-at-5.15.38-PM.png 2x [19659009] Enlarge <span class= / the branches of the right angle of the hollow tube system formed by the early fungus.

That, by this, is not surprising. The scary is how big these fossils are. While the layers that live on them are not covered in dating, there are close layers. A layer below is identified as up to a billion years old. On the other side of the stratiographic sandwich, there is a layer of 900 million years old. They provide a 100-million-year-long window where fossils can be deposited. But even in their youngest, these fossils are almost a half billion years older than the oldest fungus we found.

Thus, the claim claims that these are really fungi are becoming critical. To do so, researchers are more likely to look at the cell wall using an electron microscope and have shown that, like a fungus, the cell wall is layered. And chemically, the wall looks like it contains derivatives of chitin, a complex polymer of sugars that make up the cell wall of modern fungi. While other organisms make chitin-this is an integral part of the insect exoskeleton, for example-many of these organisms are evidently grown later, and none of them looks like Ourasphaira giraldae .

The presence of chitin is consistent with the samples held up to acid treatment that melts the surrounding rock. And a rock layer test indicates that it has never been heated above 200 ° C since it was formed, which is low enough that chitin is likely to survive in full.

All of this, the researchers are commanding, making a compelling case that Ourasphaira giraldae is actually a fungus, despite its clear age. They argued that this was part of a group of beginnings that ultimately resulted in Dikarya a subkingdom which included mushrooms.

What does it do there?

Perhaps the above sentence should read "age," rather than "the other." As mentioned earlier, gene content studies and fungi sequence indicate that they are Long-lived animals, and some jobs have even been proposed by an age in the neighborhood of 900 million years. Thus, the data indicates that fossils are from around the time fungi come from. As a result, findings find molecular data on time, which should improve our estimates of when plants and animals emerge from the world of one-celled eukaryotes.

However, fungi are a major question. Currently, most fungal species are based on soil, but stones are deposited in an atmosphere of the environment. It is not clear whether fossils are derived from it or deposited only on sediments therein.

Fungi are currently playing an important role in helping to separate complex tissues of other multicellular organisms, producing nutrients and other organic materials available in the ecosystem. It is possible that they played similar role in helping to break the complex structures developed by bacterial communities before the emergence of animal and plant life. As a half of the symbiological team that generates lichens, the fungi also help to colonize what is not in the naked rock; In that role, they may be critical in preparing the land for the invasion of other forms of complex life.

However, understanding more about living the first fungi is likely to wait for a way of identifying them without acid-

While the paper is linked below makes argument that Ourasphaira giraldae is a fungus, a previous paper describes its discovery, along with a range of other microfossil species.

Nature 2019. DOI: 10.1038 / s41586-019-1217-0 (About DOIs).


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