Wait - scientists discovered a new branch to the tree of life?

[Magic_Hat]

Just something I saw briefly online and unfortunately didn't read the entire article. Something about scientists discovering a new organism that didn't fit into any existing branch of life or something.

Anyone know more about this and want to elaborate? Was a new biological Kingdom discovered?

[factotum]

The only obvious thing I found on a search was this article, but it's from four years ago so I've no idea if it's the one you saw:

https://www.bbc.co.uk/news/science-environment-29054889

[Khedrac]

I don't know the news story you are referring to, but when one gets outside the best known two (plants and animals) the "tree" of life gets wierd, and I think there is some debate about what is what.

When I was at school they broke it up into fungi, slime moulds, bacteria and (I think) protozoa. I believe the current theory potentially splits fungi into two kingdoms, "bacteria" into several (e.g. extremophiles are no longer classified as bacteria) and the rest into a lot more. So whenever anyone finds something that is not in one of the main groups its actual "kingdom" is going to be debatable (probably because there are so few known examples of these working out relationships is very hard).

[Mechalich]

I think he may be referencing this paper (https://www.nature.com/articles/s41586-018-0708-8.epdf?referrer_access_token=KWec1HOgZdDjxDZAQf1Gf dRgN0jAjWel9jnR3ZoTv0N7ymnE41blEleCxeh33GgT5RYbwpr S7kMs9xyti6bH1BC_bUPQpE6ONJZlFos7QmIotjchpyuEvDK3W 3qW6EMWaUQV7P9_uZngZolWGjB3hS1QynfHKbfHsM-w0BZlf_29vzZZ6e0hq6B1zwd-XIWFhFeGwzS89PnFAxQGg0scar5lIW6blSSJO_FKVPfo04INq0 fGaR7WmEXweg1MsWXk&tracking_referrer=www.cbc.ca) in Nature.

Said paper describes the genetic analysis of a rare group of soil-dwelling eukaryotic microbes called Hemimastigophora which apparently establishes evidence for their placement as a supra-kingdom group within the Eukaryota - increasing the number of supra-kingdoms in the eukaryotes from 6 to 7. For comparison all animals and fungi are found within a single supra-kingdom, the Amorphea (https://en.wikipedia.org/wiki/Unikont). Note that this is not a newly discovered group of microbes, it's just the first time anyone managed to find them and catch enough to grab some DNA for analysis.

This discovery, if confirmed, represents a big deal in the overall taxonomy of basal eukaryotes, but that's, um, kind of a rarefied field. It is broadly interesting in that it seems to have a potential impact on where the root of the eukaryote tree is located, meaning it informs us about the nature of the common ancestor of all eurkaryotes, and thus ourselves, but the headlines being offered in the popular science press and rather overblowing the nature of this discovery. Someone sequenced some rare microbes, they turned out to be far more evolutionarily isolated than expected, and now the basal eukaryotes tree will need to be adjusted. Considering how little we actually know about many of the less common eukaryotic microbes - which humans don't pay much attention to unless they cause diseases - this is a cool and surprising finding (surprising enough to get published in Nature anyway) but its not any sort of taxonomic earthquake.

[Knaight]

New branches also get discovered pretty routinely, and it gets more and more routine the lower the level of taxonomy is. This particular one sounds pretty high up if it is the suspected paper, but that's still a lot less momentous than, for instance, the discovery of Archaea as a distinct domain from Bacteria. We found some weird life of a type we know we haven't researched that thoroughly, but it's still much more closely related to us than either bacteria or archaea are.

[Eldan]

I'll have to hunt down a proper artcile, but the short one I said that it probably is a new kingdom, yes. They look like this:
https://cms.qz.com/wp-content/uploads/2018/11/Screen-Shot-2018-11-17-at-11.00.47-AM-e1542470552858.png?w=1600&h=900&strip=all&quality=75
And they don't seem to fit any of the existing kingdoms, though only two species are known.

The current tree of life, as I know it, still looks mostly like this at the highest level:
https://upload.wikimedia.org/wikipedia/commons/thumb/7/70/Phylogenetic_tree.svg/440px-Phylogenetic_tree.svg.png

So the three main branches (domains) are Bacteria, Archae (formerly extremophile bacteria or archaebacteria, sometimes) and Eukaryotes.

Clasically, there used to be five or six kingdoms (Animals, Plants, Fungi, Protists, Bacteria, sometimes Archaea as a sixth), but that view is pretty much gone now. There's tons and tons and tons of braches of the Eukarya now, this is just a new one.

https://upload.wikimedia.org/wikipedia/commons/thumb/2/2c/Eukaryota_tree.svg/1052px-Eukaryota_tree.svg.png