558M-year-old fossils identified as oldest known animal

https://www.theguardian.com/science/2018/sep/20/558m-year-old-fossils-identified-as-oldest-known-animal

by Hooke • 8 years ago

195 89 8 years ago

theguardian.com

throwaway2048• 8 years ago

Does anyone have any details about how they know the bio markers were the result of cholesterol?

brennebeck• 8 years ago

Up above there’s a link to the paper: https://news.ycombinator.com/item?id=18050904

fifnir• 8 years ago

The paper: http://science.sciencemag.org/content/361/6408/1246

Here's a bit more on what they did:

We applied a new approach (17) to test the lichen, protist, and animal hypotheses by studying biomarkers extracted from organically preserved dickinsoniids. Hydrocarbon biomarkers are the molecular fossils of lipids and other biological compounds. Encased in sedimentary rock, biomarkers may retain information about their biological origins for hundreds of millions of years. For instance, hopanes are the hydrocarbon remains of bacterial hopanepolyols, whereas saturated steranes and aromatic steroids are diagenetic products of eukaryotic sterols. The most common sterols of Eukarya possess a cholesteroid, ergosteroid, or stigmasteroid skeleton with 27, 28, or 29 carbon atoms, respectively. These C27 to C29 sterols, distinguished by the alkylation pattern at position C-24 in the sterol side chain, function as membrane modifiers and are widely distributed across extant Eukarya, but their relative abundances can give clues about the source organisms (24).

stareatgoats• 8 years ago

The article states that the fossil was "an animal", without further explaining what actually constitutes "an animal", or what characteristics made it unique compared to other organisms at the time (or now for that matter). Maybe it's evident to people in the field, to a layman (like me) the term 'animal' is fairly fuzzy.

I went to Wikipedia and found this definition: "With few exceptions, animals consume organic material, breathe oxygen, are able to move, reproduce sexually, and grow from a hollow sphere of cells, the blastula, during embryonic development".

So these 'Ediacarans' fall into this category?

ajross• 8 years ago

They mean "an animal" in the cladographic sense as being part of the same evolutionary tree as modern animals, and not e.g. lichens or funguses. Specifically, they seem to have detected cholesterol (or some decay product thereof maybe) in the fossil, which is a lipid that only animals make.

The identity of the ediacaran fauna has long been controversial. They don't "look like" modern animals (all of whom descend from forms that appeared later, in the cambrian explosion), so they're hard to place. This is a big, big result if it holds up.

FWIW: this is the Wikipedia article you want to be reading: https://en.wikipedia.org/wiki/Ediacaran_biota

gwern• 8 years ago

Lowe explains it a bit more: http://blogs.sciencemag.org/pipeline/archives/2018/09/21/sit...

jasonlotito• 8 years ago

Now, by identifying the remains of organic matter on newly discovered Ediacaran fossils as ancient cholesterol, the scientists have been able to confirm Dickinsonia was an animal, which makes it the oldest known animal.

HarryHirsch• 8 years ago

It's remarkable that the components of the nerve system are very ancient and were all in place in the ur-bilaterian.

mentos• 8 years ago

It’s crazy how life just kept building and building on itself. I feel like there were so many opportunities for life to hit a ceiling and never evolve past X stage but yet somehow we broke out.

ur-whale2• 8 years ago

Given enough starting points, any local optimizer will eventually crawl out of local extrema.

mcguire• 8 years ago

If I recall correctly, the division between prokaryotes and eukaryotes took billions of years. Multicellular life was another big step.

Everything after that is easy. I remind myself that every morning. :-)

nindalf• 8 years ago

The environment kept changing too. Even if an organism evolved to a local maxima where it was the master of it's domain, the climate or geography could change. Or a giant meteor could fall on it's head. At that point, the maximas change.

yborg• 8 years ago

It's remarkable how ancient life is in general. Stromatolites have been identified in basically the oldest rocks you can find at ~3.7 Gy and this requires full-fledged bacteria. This implies that the very earliest beginnings of self-organizing and propagating biological systems are much older than that, and somehow evolved on an Earth being regularly struck by Chixculub-sized impactors and much more active volcanism. Either the process of evolving life is easier than it seems, or life on Earth has rolled the hard six an awful lot.

andrewflnr3• 8 years ago

This really makes me wonder why we seem to only have one common ancestor. It's starting to look like life happened really early, which means it's really easy, which means it should have happened more than once.

quotemstr• 8 years ago

I've always been a bit disappointed that evolution basically fixed all today's high level body plans about 500 million years ago. Lots of evolution since then has involved turning the crank on incremental and higher-level improvements (most famously, intelligence), but I don't see a lot of innovation in basic biomechanics.

It reminds me of how everyone is willing to experiment with new neural network training algorithms in the software world, but you need tremendous resistance trying to change parts of POSIX to suck less. It's as if in both nature and computing, there's some conservation in the amount of experimentation we're willing to tolerate.

solarengineer• 8 years ago

When I read such news, I wonder how people reconcile such discoveries backed by scientific validation, with religious texts that provide other timelines and explanations.

checkyoursudo• 8 years ago

The few YEC people I've read who actually attempt a reconciliation, rather than just ignore it, tend to disbelieve the dating methodologies.

ur-whale2• 8 years ago

They don't, or rather don't feel the need to:

Each story lives in parts of their brain that are entirely segregated from one another.

zw1234562• 8 years ago

I can give one example explanation. My Father is an evangelical Christian (FYI, I am not, I am an atheist and a science enthusiast). I have asked him this exact same question out of curiosity. Here is the answer he gave (albeit just one perspective). He said "God is so powerful that he can do anything including placing all that evidence there to test our faith". That shuts down any reason to continue a conversation (needless to say this is a topic we generally avoid).

Someone once said (not sure the attribution) "never try to reason with someone who has irrational beliefs".

apocalypstyx2• 8 years ago

Which, of course, leads to an even better double-bind, in that it creates a situation of functional equivalence, because, if God makes the universe look and operate as if it is X billion years old, all inquiry and prediction based upon evidence of that conclusion will, by definition, be accurate. So it may not be the "truth", but from the perspective of living in it, that doesn't matter in the least.

And if it only comes up as a matter in the afterlife, (that is, heaven doesn't like the given individual for acting upon the lie) there's another twist in the bind presented: that is God wants the given individual to live, but to do so requires interfacing with the rules of physical reality, which means accepting the predictive power of the "lie".

rumcajz• 8 years ago

Bertrand Russell: "But if once such possibilities are admitted, there is no reason to place the creation of the world at one point rather than another. We may have all come into existence five minutes ago, provided with ready-made memories, with holes in our socks and hair that needed cutting. But although this is a logical possibility, nobody can believe it."

yeukhon3• 8 years ago

I downvoted you because people who have religious faith are not always irrational people. This is a cruel way to judge those who believe in higher beings. Watch your words, seriously.

My response is simply that we concept of time in religious text is not what we think it is. I think science exists and God also exists. Plenty of scientisits believe in God and science at the same time. Are you going to quote and say they are also irrational? Sigh. I may be an angry engineer but I don’t think you should imply all of us as irrational. Don’t do that. You are insulting everyone who believe in a religion for having belief in “irrational beliefs”.

lisper16• 8 years ago

Your father's beliefs are not necessarily irrational, they are just based on different assumptions. Your assumption is that the order in the universe arises from causality and physical law. His assumption is that the order in the universe arises from purpose, i.e. he believes in teleology. That is not in and of itself irrational.

posterboy• 8 years ago

Taking the response in good faith I would assume that it's just showing the way the debate could go. It's rather constructive, whereas asking why repeatedly, seeking to arrive at a contradiction, is a fool's errand that may work both ways. Proof by contradiction is an important tactic to weed out misconceptions, but the strategy for communication is to find common agreement. Faith is a loaded term, so in effect the response opens up the meta level to your believes about faith. Indeed, I wouldn't go there out on a limb, either, if I don't have anything to add.

zw1234562• 8 years ago

I am not sure it is ok to reply to yourself, but I was not sure where to put this. First, I appreciate all the thoughtful comments and would not down vote any of them.

Just to level set, when I say that I think my Fathers beliefs are irrational, I don't mean that in a derisive way, I simply mean they are not fact based or not based on logical reasoning. That is sort of the basis for faith I think. But I am not being disrespectful, I simply choose a different path that is science based.

andrewflnr3• 8 years ago

The Bible repeatedly states that God cannot lie. Your father is making God out to be a liar. If it comes up again, if you want to start a fight, that's a direction you could go.

Brockenstein3• 8 years ago

He said "God is so powerful that he can do anything including placing all that evidence there to test our faith".

So his God is a deceiver. It's impossible to know the truth about anything in that universe. Because you don't know, can't know, when God is putting a finger on the scale.

That sort of reasoning reminds me of:

http://www.talkorigins.org/faqs/faq-god.html

Q7. So if God directed evolution, why not just say he created everything at once?

Mainly because all the evidence suggests otherwise. If God created the universe suddenly, he created it in a state that is indistinguishable from true age. If he did create it that way there must be a reason, otherwise God is a liar. Whatever that reason may be, a universe that is exactly like one that is old should be treated as if it were old.

gbear605• 8 years ago

One simple technique is to say that the fossils or whatever were intentionally placed there to make the world seem to be older than it is.

apocalypstyx2• 8 years ago

They give their children story books with pictures of a tyrannosaur trying to dog-paddle with its pathetic little forearms, while the ark sails away in the distance (because that's why they don't exist no more).

Source: my childhood.

stephen_g• 8 years ago

Not sure about other belief systems, but most scientists who are Christian at least would consider your question to be a ‘category error’. Science is generally limited to explaining questions of ‘how’ things happen, while the belief in a creating/sustaining God is believed to be explaining questions of ‘why’.

Professor of Mathematics and Christian John Lennox had a fairly good quote saying that he doesn’t believe as a “God of the gaps” but a “God of the whole thing”, in that a Christian doesn’t believe that science being able to explain mechanisms diminishes God in any way, because if a God is in control/sustaining the universe then pretty much everything that science explains can be simultaneously brought about by God.

The whole young earth thing is strangely popular in America but not really strongly held in general mainstream Christianity or (I believe) in mainstream Judaism. There is plenty of scholarship going back thousands of years (back to Augustine circa 4th century AD, or even Phillo of Alexandria in 1st C) who believed that the author of Genesis didn’t intend the first few chapters to be read as attesting literal time periods or mechanisms but convey theological truths about God and humanity.

So while fundie YEC people would probably have a problem with this finding, generally mainstream believers and Christian scientists have no problem with this as just being a step in a process that God causes to occur to intentionally bring about life including humans.

elboru2• 8 years ago

Thank you I think you explained it really well.

The whole young earth thing is strangely popular in America but not really strongly held in general mainstream Christianity or (I believe) in mainstream Judaism.

I’m not American, so it has always been weird to me how the early earth thing is widely associated with Christianity, I mean, I have no doubt there must be people really believing on it. But from a non American and non Protestant Christian point of view it is just weird. But my guess is that it must be associated with “Sola Scriptura” and the free and individual interpretation of the Bible some Protestants believe in.

drb91• 8 years ago

The mind is agile and can reconcile many things—for one, all evidence is falsifiable by a god.

I’m more curious what people psychologically get out of taking the bible literally. It wouldn’t make me happy.

LargeWu• 8 years ago

Many mainline Christians treat most of the Old Testament, especially scientifically implausible parts like Genesis, as tradition, and not literal fact. These are things that are perhaps taught in Sunday school to children, but not treated very seriously from a historical or scientific perspective.

This very morning in my church discussion group, we each had a list of questions to discuss our perspective on. This particular gal had the question, "What's your favorite traditional Christian symbol?" Her answer was "the Jesus fish, and the evolved Jesus fish with legs". They are not incompatible given how our denomination tries to understand God.

skeleton• 8 years ago

One day I wondered where dinosaurs fit into christianity. I know next to nothing about christianity but I think it includes the belief that humans were on Earth pretty soon after Earth's creation, which meant either christianity rejected the dinosaur's existence or they lived alongside humans, which would be a pretty neat scenario to imagine.

If I recall correctly the common explanations I found were that humans did in fact live alongside dinosaurs, and that dinosaurs lived and died within the first few days of their creation for whatever reason.

One article I read on a christian website also said that the dating of dinosaur fossils by scientists was incorrect because bones don't have timestamp labels on them so there's no way one could know.

In regards to "I wonder how people reconcile such discoveries backed by scientific validation" I think it's quite often simply unsubstantiated rejection.

gpm• 8 years ago

I've never understood why this is an issue.

If I'm god, and I'm creating a planet for humans, and I made humans the curious beings that they are, would I:

a) Create an earth that is boring with no history to dig into and explore

b) Create a rich and storied history with things for them to wonder at

Now, I mean, if I was god I would chose option b. Even in the alternate reality where I would personally chose option a I don't see any reason to think that the actual god couldn't have chosen option b.

I'm not religious or well versed in Christianity, but I'm not aware of any reason why option b is inconsistent with the bible (the one possible exception is the flood story, but that is easily explained away by god fixing the earth afterwards).

aggie• 8 years ago

Your argument is a plausible retcon of the bible, but the "God made it that way" mechanism is essentially infinitely flexible and unfalsifiable. The problem with that is for many people, falsifiability is an important aspect of evidence-based belief (judged by predictive or explanatory value).

Even if your explanation for why there are fossils etc. sounds sort of reasonable, if you grant this reinterpretation of the Christian creation myth, you've established that the goalposts can be moved, and from there you can find a way to move them for just about anything. Imagine we uncover a convincing, contemporaneous writing of Jesus' proclamation that he is merely a human. You could say, "Well God put that writing there to test our faith."

chiefalchemist2• 8 years ago

I have a similar argument / belief. Simply put, if God was able to create "the heaven and the earth" - an effort that is well beyond our (limited) imaginations - then adding in some doodads (e.g., fossils) and whatnots (e.g., what appears to be geographic history) is a relative piece of cake. I believe to think otherwise is naive and lacks imagination.

I mentioned this possibility to an atheist friend of mine and it stopped him in his tracks.

Note: I'm also not heavily religiou by any means. But the odds of there being things beyond our imagination and beyond our knowledge are extremely possible.

As a side note, I find it kinda funny that Elon Musk can says (paraphrasing) "we live in a world created by someone / something we cannot see and we ultimately cannot understand" and no one gets upset. But isn't that presumption the basis of most theoism-based religions? No offense, but Some Musk states the obvious and that suddenly profound. Maybe I'm missing something?

558M-year-old fossils identified as oldest known animal

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