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The Tree of Life Consolidates
Roland Piquepaille writes "The Tree of Life is an expression first used by Charles Darwin to describe the diversity of organisms on Earth and their evolutionary history. There are only two life forms, — eukaryotes, which gather their genetic material in a nucleus, and prokaryotes, such as bacteria, which have their genetic material floating freely in the cell. Until recently, eukaryotes, which include humans, were divided into five groups. But now, based on work by European researchers, the Tree of Life has lost a branch. After doing the largest ever genetic comparison of life forms they concluded that there are only four groups of eukaryotes."
The more we know, the more we know that what we knew was wrong.
Or, as a coworker of mine used to say when we realized we didn't know what we were doing: "Everything you know is wrong."
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
I should be more careful with that chainsaw. Poor tree, only 5 branches , I hope it survives...
mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
What else will science rob from us before we decide enough is enough?
Fabien Burki1*, Kamran Shalchian-Tabrizi3, Marianne Minge3, Åsmund Skjæveland3, Sergey I. Nikolaev2, Kjetill S. Jakobsen3, Jan Pawlowski1
1 Department of Zoology and Animal Biology, University of Geneva, Geneva, Switzerland, 2 Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland, 3 Department of Biology, University of Oslo, Oslo, Norway
Abstract
Background
Resolving the phylogenetic relationships between eukaryotes is an ongoing challenge of evolutionary biology. In recent years, the accumulation of molecular data led to a new evolutionary understanding, in which all eukaryotic diversity has been classified into five or six supergroups. Yet, the composition of these large assemblages and their relationships remain controversial.
Methodology/Principle Findings
Here, we report the sequencing of expressed sequence tags (ESTs) for two species belonging to the supergroup Rhizaria and present the analysis of a unique dataset combining 29908 amino acid positions and an extensive taxa sampling made of 49 mainly unicellular species representative of all supergroups. Our results show a very robust relationship between Rhizaria and two main clades of the supergroup chromalveolates: stramenopiles and alveolates. We confirm the existence of consistent affinities between assemblages that were thought to belong to different supergroups of eukaryotes, thus not sharing a close evolutionary history.
Conclusions
This well supported phylogeny has important consequences for our understanding of the evolutionary history of eukaryotes. In particular, it questions a single red algal origin of the chlorophyll-c containing plastids among the chromalveolates. We propose the abbreviated name 'SAR' (Stramenopiles+Alveolates+Rhizaria) to accommodate this new super assemblage of eukaryotes, which comprises the largest diversity of unicellular eukaryotes.
Citation: Burki F, Shalchian-Tabrizi K, Minge M, Skjæveland Å, Nikolaev SI, et al. (2007) Phylogenomics Reshuffles the Eukaryotic Supergroups. PLoS ONE 2(8): e790. doi:10.1371/journal.pone.0000790
Academic Editor: Geraldine Butler, University College Dublin, Ireland
Received: June 17, 2007; Accepted: July 26, 2007; Published: August 29, 2007
Copyright: © 2007 Burki et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Funding: This research was supported by the Swiss National Science Foundation grant 3100A0-100415 and 3100A0-112645 (JP); and by research grant (grant no 118894/431) from the Norwegian Research Council (KSJ).
Competing interests: The authors have declared that no competing interests exist.
* To whom correspondence should be addressed. E-mail: Fabien.Burki@zoo.unige.ch
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
"The Tree of Life is an expression first used by Charles Darwin"
So Charles Darwin, born in the 1809, predates the Kabbalah?
This is not the greatest
While a tree-structure is algorithmically convenient and very enticing... the "tree of life" is not a tree.
Ie it is not a "directed, acyclic graph".
Unfortunately it has 'cycles'.
Blame retroviruses; they can take genetic material from one species and insert it into the genome of another thereby creating cross-branches.
As I recall, from my genetics days, baboon retroviruses are a great example of this. Again, IIRC, domestic cats and humans both contain fragments of baboon retroviruses.
Its possible that the "Cambrian explosion" is a sign of the appearance of retroviruses on the scene.
The thing is that it is significantly harder to reason about graphs; trees are so much easier to deal with.
So its very tempting to see things like this as trees and to 'simplify out' the nasty cross-branches.
(I've studied genetics, computer science, logic and discrete math)
In the free world the media isn't government run; the government is media run.
Let's not forget that many scientists think there are three domains (Prokaryotes, Eukaryotes and Archaea). Archaea are very similar to Prokaryotes in that they don't have a nucleus, but they also share many features with Eukaryotes, including several key enzymes. Due to their similarity to the two other lineages, it is thought that Archaea may in fact be the grand daddy of all life. http://en.wikipedia.org/wiki/Archaea
Anyone who says "Evolution is taken as faith" or doesn't understand that the theory is based on the evidence, and that new evidence means changing the theory can look at this and shut up. A rather fundamental point was proposed to be rather fundamentally different based on new research and that's just fine. Whether it pans out or not, this is a beautiful example of the glory of science.
I live in constant fear of the Coming of the Red Spiders.
Two? For several decades, I thought most biologists considered life as being divided into three main branches ("domains"): eukaryotes, prokaryotes, and archaea.
http://www.geoffreylandis.com
When I was in 9th grade (I guess about 10 years ago!), there were five "kingdoms": bacteria, protista, fungi, plantae, and animalia. Three years later, there were six: archaea, monera, protista, fungi, plantae, and animalia.
Now there are branches? And four of them? On a tree? That's news to me. But it's all a matter of naming and grouping, so I guess you say potato, I say tomato.
In the pursuit of knowledge, every day something is added.
In the pursuit of understanding, every day something is removed.
In Xanadu did Kubla Khan
A stately pleasure dome decree
This is a bit over the top. It's not like there's a single canonical "Tree of Life" that's going to have to be changed across the board; there's endless (mostly self-promoting) squabbling over what should be considered fundamental branches, to which this is yet another entry.
Frankly, if this were as important as they make out, it would be in Nature, not the if-it's-not-objectively-wrong-it's-in PLoS ONE.
"...the largest ever genetic comparison of higher life forms on the planet"? Maybe, I guess it depends what dimension you measure "largest" on.
What I'm listening to now on Pandora...
Yes, being able to correct mistakes is the glory of science. But being right the first time is the glory of religion.
When religion doesn't get it right, people abandon it completely. When science doesn't get it right, they say, "well, that's just part of the process..."
Each particular method has its strengths and weaknesses:
The key, I think, is not to confuse the various levels of truth. Those who take religion as if it were a scientifically-verifiable fact are just as confused as those who think scientific theorems are as reliable and trustworthy as the Gospel or mathematical proofs. There is a large difference between the three, and understanding the subtle limitations of each is just as important as understanding the ideas they espouse.
The society for a thought-free internet welcomes you.
Saying that the "Tree of Life" was first used by Darwin to describe evolutionary relationships should be taken with a grain of salt. The use of a "tree" to describe decendants and family relationships dates back to (at the very least) pre-Roman times. Paintings depicting lineage were long adorned with leaves and fruit. There is a reason that the Bible used a "tree" to signify life -- because the symbolism of a trunk, limbs, shoots and offshoots was well established by mankind long before the Bible was even written. Norse mythology also used the concept of a "Tree of Life" to describe the relationships of one generation to the next: The Gods at the trunk, the more recently 'evolved' mankind at the branch tips. (And the Runes at the roots).
I'm a big fan of Darwin. But let's not give him credit for applying some of mankind's oldest and most widely used symbols to the very thing it typically symbolized.
------ The best brain training is now totally free : )
Your "tree of life" has inter-connecting branches?
That sounds a little....incestuous....no?
A goal is a dream with a deadline
- Born, Live, Read
/., Die
Non-geeks, substitute "ReadIt must have been something you assimilated. . . .
I never heard of "PLoS ONE", it claims to be a peer reviewed journal at least. If this was ground breaking I'd expect it to be published in Nature though. The "PLoS ONE" website isn't loading for me at the moment, but hopefully I'll be able to read the actual article. This seems to be hoopla over definitions though, we can sort organisms into kingdoms and phyla any way we like, this seems identical to the tug-of-war over whether Pluto is a planet or a planetoid. Is it the size of the planet? Is it if an organism has x+2 mutations in a histone protein/gene it gets slotted into one kingdom or another?
:P
Hey the journal finally loaded, here is a link to the actual paper: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0000790, although its taking a long time to load for me, and it's not even slashdotted yet.
Submitter was close, but not quite right, there are three kingdoms. Eukaryotes, bacteria and archaea. While archaea may look a lot like bacteria, biologists recognize this group as a distinct kingdom in the tree of life.
Thanks for playing, please try again next time.
They haven't tested Cheney yet, we'll be back to 5 types if Congress does its job.
Holy Balista!
( http://www.youtube.com/watch?v=NBI4v40zLFE, 4:40 )
What's happened is that better information has rapidly come to the fore as genetic analysis have been done during the last 15 years. The tree has been revised several times.
The five kingdom model was already known to be wrong 10 years ago, but that information hadn't propagated to gradeschool and highschool textbooks yet. If you'd studied biology in college, your information would be more up to date.
These days there are three superkingdoms: Bacteria, Archaea, and Eukarya. (Bacteria and Archaea were formerly grouped together as "monera" or "bacteria" before it was realized that genetically they are as distinct from each other as they are from Eukarya.) Eukarya is broken into a number of kingdoms, and that number has just changed from 5 to 4. Even the 5 they were last year weren't exactly same ones that you learned in school.
I stole this sig from someone cleverer than me.
This is further proof that the Bible is the Word of God and vindicates Intelligent Design!
"The fight for freedom has only just begun." - Geert Wilders
4 supergroups? Wait, did Journey break up? Who stopped believing!
You sir are the biggest fucking nerd i've ever seen.
"those earliest primitive self-replicators, probably swapped genes a helluva lot"
Are you saying the world's oldest profession really is the world's oldest profession, or are you just calling them sluts?
What a worthless article that is.
2,000 words, and they never listed the "Before" list. And in the text following the "After" list, they implied that there's still a group of organisms not in the list, meaning all these guys really did was move some entries between two branches.
Worthless. Come back when (a) it's done and (b) it's written-up clearly enough that the facts can be listed in two sentences.
The branch was not cut, it was merged! :-)
Bet nature used GIT for that!
Only the true messiah would deny his divinity.
Play Command HQ online
Both the summary and the article made no sense whatsoever (and I am not bored enough to read the paper), can someone clarify this for me?
The "branches" on the "tree" of life are pretty much arbitrary, you could draw a single node called "Life" or you could draw every single individual organism that ever existed - both would be valid.
Are they saying that they combined two groups on some taxonomic level because they are more closely related than previously thought?
I don't know what exactly they mean by "the five groups...", but I'm pretty sure their little unreadable graphic (which, by the way, wtf?) doesn't cover all of Eukarya - is this groundbreaking research transforming one mostly unknown pet classification into another?
Then there's this: "Previously, these species were thought to be completely unrelated."
Unless I slept through something fairly major, all currently living organisms on Earth are still considered to have arisen from a common origin (or created by the gods in a flash of omnipotence, etc, etc.), so all species are related.
And of course it explains that to arrive at these conclusion they have "studied" the genes - I'm sure anything more specific would make our poor little heads hurt.
Can someone summarize what they actually did?
sic transit gloria mundi
Darwin didn't come up with the phrase "Tree of Life". It was first used in the Bible in the Book of Revelations describing Heaven. That Darwin lifted the phrase amuses me to no end. I wonder if God has enforced his IP rights on that?
Science is a moving target which is one of the reasonse we should never use terms like "scientifically proven" and should never get ioverconfident.
Engineering is the art of compromise.
I've long suspected that a few twinges of our human predilection for genocide stems from a deeply rooted evolutionary belief that we are still seated at such a table. Do unto others before they do unto you.
Up until the Cambrian era, mother nature was doing quite the nice job of covering up her dirty work. Then she tried to hide the equatorial crime scene high atop a cliff face of a mountain range in desolate southern Alberta. She was just in the process of tuning up a rabid strain of stampeding bison to cover off the eastern approach, but then some upstart seafaring albino monkey got the notion that India lay due south of Newfoundland, and her reputation has never been quite the same since.
Our understanding of the world is, and will always be, approximate.
Science is a process by which we improve that approximation. Nothing we used to know is now wrong. Some things we used to roughly understand we now understand better.
It appears that the Eukaryotes emerged sometime over a billion years ago. As far back as we could figure out, it looked like there were five groups of them, but we didn't understand which of those groups were more closely related to each other. Further research has now refined our approximation, and it appears two of those groups are more closely related that the rest.
So, certain single-celled organisms are understood to be more closely related to certain other single celled organisms than previously thought. Compared to any of the organisms involved, you're still more closely related to certain other single celled organisms, as well as all animals and fungi. If that shakes your world view, you need to get out more.
Ultimately, this is all moot. In 2029, the Tree of Life will get what's coming to it, as administered by a giant hexapedal cloaking tank with miniguns for arms.
Why do biological names look like an explosion in an alphabet soup factory? At first, I thought this was because the classicist biologists had all learned Latin, but I think this vandalism, this hacking a branch off the tree of life reveals the true answer. The vandals ARE setting off explosions in an alphabet soup factory and writing down the words that form.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The assumption of single origin should not be trusted.
Boffoonery - downloadable Comedy Benefit for Bletchley Park
To see who loses out on the next episode of... Survivor: Supertypes!
"Teach a man to build a fire, and he's warm for a day. Set a man on fire and he's warm for the rest of his life."
Hey! Where have my missing eukaryotes gone?
Don't be apathetic. Procrastinate!
There! Are! Four! Branches!
they decided that Pluto isn't a planet?
The higher the technology, the sharper that two-edged sword.
There is also no real prohibition against shooting people in the Christian Bible.
I get what you're saying: abortion is murder, and to say that there's no prohibition against abortion implies that specific types of murder are not specifically prohibited. It's a wry comment and one that flew right over the head of most of the people that responded.
The real problem is that murder is effectively undefined in the Bible. Clearly there are some forms of killing of other humans that are allowed: war in the name of God, stoning adulterers, self-defense, etc. There are also ample examples of killing of non-humans that is allowed: kosher animal slaughter, animal sacrifice, slaughter of the livestock of enemy nations that you're at war with, etc.
What's not explicitly clear in the Bible is whether or not the unborn can be "murdered" per se. The question of when someone becomes a human being with a soul (and whether the possession of a soul or any other factors are even relevant) is completely unanswered in the Bible. The whole "life begins at conception" movement is taking a reasonable stance (with respect to the scripture), but it is a stance that is largely textually unsupported without some really extreme assumptions about the meanings of certain words and the knowledge of Biblical writers about fetal development.
In essence, it's a point of dogma which is based purely on non-textual philosophical decisions. It's also not the only valid interpretation. Some Rabbinical scholars have asserted in the past that a person only gains a soul on the taking of their first breath (neatly side-stepping all the issues of God's fairness with regards to miscarriages). Some people have pointed to Exodus 22:21-23 (punishment for striking a pregnant women and causing a miscarriage) but don't really read the next couple of verses which make classic eye-for-eye, tooth-for-tooth restitutions that make it ambiguous whether this is meant to apply to the death of the child or the mother (babies don't have teeth, but neither are they likely to be burned by having their mother struck).
Anyway, the Bible simply doesn't talk about abortion at all. The closest thing it talks about is miscarriage through misfortune or violence, and the focus of punishment is usually framed in terms of the loss of the parents (father) instead of the loss of the life of the child.
....oh nevermind talking to u guys is a waste of time...
As long as us Linux users don't have to share a branch with Windows users, I'm OK with it.
Have gnu, will travel.
Honestly, I never new that. I thought eukaryotes were like some sort of fossilized microorganisms, or something.
Isn't there a separate branch for lawyers?
Table-ized A.I.
I think viruses are alive. But they're neither eukaryotic nor prokaryotic, unless you call the whole planet their "cell". Where are they in the tree?
--
make install -not war
The food pyramid has little basis in science.
People interested in their own wellbeing should have ignored the food pyramid.
A good clue was it was produced by the Department of Agriculture.
The last I checked those silly food pyramids and rings and crap weren't produced by the Department of Health, or even the FDA.
Think about it honestly, has the US DoA's top priority ever been the health of the US citizens?
Go figure.
I really like how they use genetic analysis to determine groups of organisms they originally thought were unrelated, actually were related.
:D
Wouldn't it be wild if they came across an organism, but couldn't make it fit into any other group, and ended up concluding that it wasn't a lifeform that originated on Earth?
There is no America. There is no democracy. There is only IBM and AT&T and DuPont, Dow, General Electric, and Exxon
Important Discovery
"Kinship says a lot about shared traits. Our findings can be important in many fields, such as in the study of the development of life and in the manufacture of new medicines" says Shalchian-Tabrizi in an interview with the University of Oslo's research magazine Apollon.
"Our knowledge of organisms and the development of medicines are often based on comparative studies across species. It is, therefore, essential that we know the relationships between the largest groups in the great diversity of eukaryotes," he adds.
The research group has, for example, found that brown algae and silica algae, and groups of single cell organisms like the malaria parasite, marine foraminifera, and the green sun animalcule (acanthocystis turfacea) actually belong to the same group. Previously, these species were thought to be completely unrelated.
Fewer Events
"The Tree of Life tells the story of life on Earth, and our research can say something about how quickly life developed. Our discovery suggests that there were fewer big "events" than we have previously assumed in the development of higher life forms. The more we know about the branches on the Tree of Life, the more we can find out about life's Big Bang, the beginning of life on Earth," says Shalchian-Tabrizi.
"By digging down into the historical layers with the help of phylogenetic reconstruction, where we can find out about kinship between organisms at the genetic level and we can find answers to questions about how new traits developed. We are working, in a matter of speaking, with genetic archaeology. In this manner, we can also discover the cause of the Earth's biological diversity," says Jakobsen.
Emphasis mine, of course.
Just -1, Troll talking to another.
Try quoting the ENTIRE SENTENCE:
"The Tree of Life is an expression first used by Charles Darwin to describe the diversity of organisms on Earth and their evolutionary history."
Did the Kaballah use it in that sense?
PVCS? 'coz, as a Subversion admin I cannot imagine loosing a branch!
Naaa, I didn't RTFA, did I have to?
Those who can make you believe absurdities can make you commit atrocities. - Voltaire
Wow, usually these phylogenetic trees are not rooted, which means you can divide them any way you like. So, the really amazing story is they rooted the tree of life! Good job, especially since we actually thought it was a ring of life.
Just callin' it like I see it.
this is decent:
http://en.wikipedia.org/wiki/Solipsism
Yes. It did, and does. Kabbalah is an ancient Jewish tradition. You can read a lot about it online. It has to do something with exploring the true names of God. Interestingly, it also has to do with much more than that, and how God is tied to the entire universe... i.e. it's about the describing the diversity of life on earth and it's evolutionary historical ties to God. In later years, it led to alchemy, which in turn led to bastardizations of itself like Enochian Angel Magick and the study of biology.
Parent stole my post.
I intended to point out that the summary was either inaccurate or constructed with poor syntax. i.e. Was Darwin "first to use the expression" or first to use the expression "to describe the diversity of organisms on Earth and their evolutionary history."
Ignorance is curable, stupid is forever.
i'm working on an artificial language and need some help finding charts/illustrations of the tree of life. If you know of any sites or books with detailed trees, please post them here or send them in a PM.
Thanks in advance!
A
"In the pursuit of knowledge, every day something is added.
In the pursuit of understanding, every day something is removed."
i just added this to my quote collection. Brilliant!
Utilizing the synergization of benchmark e-solutions to pre-workaround action items!
I'm tired, eukaryote.
I swear to God...I swear to God! That is NOT how you treat your human!
After all, if colleges can give people who never went to college an honorary Ph.D., surely astronomers can give celestial bodies an honorary Planet-hood Descriptor.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
It is estimated that less than a percent of microorganisms have been identified. You can go to your back yard and discover something new to science. Go ahead and do that right now - i'll wait. The article suggests that this new finding is the not end of the issue. So clearly, instead of changing the textbooks and making students buy the new one, the textbooks should be on line, where they can be updated and disseminated quickly. For example:
http://www.textbookrevolution.org/
So, Archaea, Prokaryotes, Eukaryotes and Viruses. Eukaryotes come in four groups: Plants, Opisthokonts (that's us and other fungi, etc.), Excavates, and SAR.
The article does not eliminate Prokaryotes, or combine Archaea with something else, or mention Viruses.
So, what's the current consensus on Prions?
-- Stephen.
Your reading of "to describe..." as binding more strongly to "Charles Darwin" than "first used by" is possible, but very unnatural. It's also clearly not intended by the author, as it would be an extremely awkward and ambiguous way to express that concept. Instead, the author would have written something like, "Charles Darwin was the first to use the expression 'The Tree of Life' to describe the diversity..."
Face it: the author doesn't know the history of the term. That doesn't render the entire article worthless, but the misinformation warrants correction.
It was in the book of Genesis first.
http://en.wikipedia.org/wiki/Tree_of_Life_(Judeo-Christian)
what life-form group Americans belonged to?
I say reptiles.....
Roland,
"There are only two life forms, -- eukaryotes, which gather their genetic material in a nucleus, and prokaryotes, such as bacteria, which have their
genetic material floating freely in the cell."
How about writing using proper punctuation? What is ", --"? Simply throwing more marks in there doesn't actually make it better.
You could write it with a colon.
There are only two life forms: eukaryotes, which gather their genetic material in a nucleus, and prokaryotes, such as bacteria, which have their
genetic material floating freely in the cell.
You could add more punch. This form also gets rid of the word which.
There are only two life forms: eukaryotes and prokaryotes. Eukaryotes gather their genetic material in a nucleus. Prokaryotes have their genetic material floating freely in the cell. Humans are collectives of eukaryotes. Bacteria are prokaryotes.
I was in the branch, Now what the ... do I do?
His theory is much better than the previous theory proposed by Lamarck which did not pass the tests against it.
But the fact that there is a theory to explain evolution doesn't make evolution any less of a fact.
You can't take the sky from me...
qwerty
The "condemnations" of homosexuality on the one hand and shrimp on the other are not the same, using entirely different words. (Just because the 400 year-old language in the KJV uses the word "abomination" in both passages, doesn't mean the Hebrew is the same.)
(the following was shamelessly taken from godhatesshrimp.com)
But, some of you say, in the original Hebrew, there are two words that were both translated as "abomination": to'eivah , for homosexuality, and sheketz , for non-kosher food.
Our answer to that is:
But, still others say, what about 1 Corinthians? Paul says... Well, the easy answer is, this site was never meant to be a comprehensive rebuttal to following outdated religious rules. The less easy answer is that, in his letter to the church in Corinth, Paul referred to restrictions listed in Mosaic law in the Torah, a.k.a. the Old Testament, so basing your argument on Paul's reference to a source that was declared invalid by Jesus (see above) is a shaky bit of reasoning. Or to explain it more clearly, we'll quote a friend who is studying to be a minister:
With the first link, the chain is forged.
What did these researchers make go extinct? They wiped out a whole kingdom? Awesome. Humans are awesome.