What caused the Cambrian explosion?
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- เผยแพร่เมื่อ 26 ส.ค. 2015
- For most of the Earth's history, life consisted of the simplest organisms; but then something happened that would give rise to staggering diversity, and, ultimately, life as complex as that which we see today. Scientists are still struggling to figure out just what that was.
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What is not really explained well in this video is the fact that simple single celled life seems to have developed almost the moment liquid water was available 3.5 billion years ago. So it would appear the initial creation of basic life was relatively easy. It was the sudden jump to multi-cellular life after 3 billion more years that remains one of the greatest questions of biology.
Your dates are way off. Have you come to Christ yet, or still think you came from a rock?
@@ChristianityRecap 💀💀🤣🤣
@@ChristianityRecap the fact that you believe anything other than humans being highly evolved primates is astonishing. We are animals... nothing more nothing less.
@@ChristianityRecap bro this is one of the worst attempts at evangelism I’ve ever seen
@@samfrazee7022 thank you!
never knew an anime would connect me to this prehistoric things
dino bite I know right? I watch ONE video on the weird centipede thing and now my recommendations are full of marine biologist documentaries
@@user-hv7zb5ps3t LOL SAMEE
@@user-hv7zb5ps3t ye the parasite thingy from Shingeki no kyojin
@@hemblem131 hallucigenia
AoT?
The reasons why people are here:
- Biologists
- Bill Wurtz
- Attack on Titan
none of them.
all of them lol hahaha
I'm here from Bill Wurtz. Never watched Attack on Titan just like I never watched The Matrix because if I ever talk about something considered "deep" I want people to know things I say come from experience and the mind, not from a movie I was inspired by and decided I'd become a wanna-be
I have an ocean obsession 🧍🏻
- Yes
- Big yes
- I don't know, I only watched the first season back when it came out and I was never interested enough to watch more xD
Unlike facebook which is utter crap, youtube may be the most useful site on the internet. Wanted to be a paleontologist as a kid, career path went elsewhere but maintained my fascination for the subject. youtube has vast amounts of material on the topic and allows the intested layman access to materials thay may have long been forgotten. Well done,,,,Oh and interesting summation. Amazing how well we have progressed in our understanding of the beginnigns of life.
I completely agree with you - Facebook is really stupid. It's a real waste of time. just an excuse to stay inside and never interact with people, "IRL". You Tube, on the other hand - as long as you stay away from (most of_ the comments, one can find an amazing amount of programs, videos, movies, and all sorts of unpredictable things which people from around the world have uploaded- everything from silly cats-trying-to-walk-on-treadmills videos to videotaped college course lectures from such institutions as Stanford, MIT, (grudgingly I'll say it:) Yale (although, of course, Harvard is so much better than Yale, but that's a different argument for another time). Anyway, if you want to find educational videos about all sorts of subjects - weather/climate sciences, astrophysics, quantum physics, anthropology, etc., etc. and, of course, there are millions of songs that are uploaded either as just a still picture-video with the song playing or else the video for the song is uploaded or even, sometimes, some uploader will create their own video for a particular song and post it, and sometimes you find whole albums' worth of stuff, i.e., a whole album in one post. Also, there are also lots of movies - both public domain ones, like so many great things from the early 30s (and a lot of these early 30s movies are actually better than the stuff that came out of Hollywood after that awful "Hays Code" -that asshole who, being an uptight stick-up-the-ass jerk & trying to kiss the govt's ass so they wouldn't clamp down & legislate Victorian morals on films-which happened anyway, up until the 60s, when taboos were finally being chopped down & flushed down the goddamn toilet! But you can sometimes catch a newer (copyrighted) movie that has either escaped the copyright-policing software that takes those down by speeding up the sound or doing some sort of tricky thing with the picture quality - sometimes it's in the form of an elliptical light in the middle of the movie that can be distracting when the scene happens to be in a dark spot - say, at night or in a darkened room, etc. Or, you may get a chance to see a newer movie if you chance upon it just in time, before it gets taken down for copyright reasons. Anyway, yes, You Tube is a great thing - I only wish all the trolls that waste so much time with their back & forth verbal catfights and temper tantrums, etc. would go somewhere else - like Facebook and stay there! -otherwise, just stay up where the video is & ignore the comments and you'll enjoy the experience much more!
Yeah, FUCK facebook. Bunch of idiots.
I tried FB briefly and quickly knew it was a huge waste of my valuable time. Time is something of which they won’t be making more. I took a look at some of the connections to my FB, and, YEESH ! many people had posted every bit of trivia as though - if they couldn’t record each meal, each trip, each day, each breath, it hadn’t existed, and they might not exist. Perhaps they do not exist, if FB takes up so much of their concentration.
TH-cam is a mess actually.
Try TED talks. Even better
Shingeki no kyojin
shhh
Aot chap 137 be like:
this is the kind of videos i subscribed for
Indeed. And one of the most fascinating topics ever.
i didnt sub but im happy you did , )
Attack on Titan refrencess
Literally, AOT bring everyone to learn biology
AOC*
Attack on Titan?
For me it was a Jeff Bezos video lol but I've also watched that episode on AOT but didn't go that deep there
The Economist: What caused the Cambrian explosion?
Me: Wait, what? The economist is looking at paleontology? What?
Nobody expects the Cambrian Explosion!
Now, THAT was unexpected!!!!!
Would've made Monty Python a lot harder to shoot.
I just made this comment elsewhere in these comments, but now see you beat me to it. First kudos to you.
There is an intervention
It chief weapon is shells and mobility. Our two chief weapons are shells,mobility and a ruthless devotion to evolution. Its three, three chief
Absolutely well done and definitely keep it up!!! 👍👍👍👍👍
they talk about eyes, oxygen but no sexual organ explosions ?
Ok, we have no idea how the Cambrian explosion occurred.
Evolution.
May be all animals created at the same time instead of evolutionary process?
No of course not. There are pre-Cambrian fossil ancestors for organisms in the Cambrian. Not many of them admittedly because soft bodied organisms are hard to find in the fossil record.
Evolution is already proven to exist.
@@chimpanzeethat3802 Yes, simply a mixture of random genetic modifications
@@chimpanzeethat3802 explain to me the evolution of the human eye.
It's the cambrian explosion!
"Wow, that's animals and stuff"
You forgot the TM at the end of the word stuff
Can we go on land now?
"NO"
Why?
"THE SUN IS A DEADLY LAZER"
Oh ok.
"Not anymore. There's a blanket"
Explosion occur because someone turn into Titan.
Consider that the Cambrian Explosion was pretty much about the arthropods which happened because of their new found ability to produce chitin. For the mollusks it was the Ordovician (and their ability to produce a calcium carbonate shell). For the Chordates it was the Silurian (and their ability to produce a calcium phosphate skeleton). It was all about the ability lay down skeletal material and HGT (horizontal gene transfer) was almost certainly the mechanism that spread the capability among related taxa.
Agreed. Former soft animals simply died and got eaten or vice versa. The one change of adding hard matter such as shells or skeletons created fossils. Just one small change and all is explained. No great time involved.
What do you mean by "soft animals"? How many cells were they composed of? Were they eukaryotes? What caused the evolution of soft animals? How did life go from single cells to multiple celled organisms?
@@wombatmobile the ancestors of the cambrian fossils, no skeleton or shell, no fossils, but they were somewhat more like animals than simple multicelular life
@@midas01tw Were they eukaryotes? How did life go from single cells to multiple celled organisms?
@@wombatmobile Best off asking a biologist those questions mate. I doubt random youtube commenters will be able to answer your questions with accuracy and explanation, you will just end up doubting the answers and forming your own incorrect ones
Aot fans anyone?
Had been watching the Beirut explosion, so when I clicked on this, the expectation that this video might mention a physical chain reaction explosion involving explosive products, thinking acme tnt that the road runner used, were pretty high. I have learnt something new and covered history for the day.
Very informative thank you :)
Now we know the Ediacarans lived alongside the Cambrians, and Anomalocaridids survived until during the Devonian
I hope we soon manage to fill the Silurian gap in the anomalocaridid record...
thank you been pondering this mystery all day and all night and i a m tired of all the conspiracy theories about it . this was succinct and based on science.
what science ?? the whole video is just showing theories with no single scientific evidence.... watch it again .. every scientist is just giving his own opinion !!
@@mohammedhasanen6291 Looks like someone didn't learn the difference between theory and hypothesis in school. Gravity is a theory, don't see you claiming it's not real
@@joshmarsh2532 … Wow, Please teach me your wisdom and tell me the difference. I think if you were living 500 years ago, you would be easily convinced that the moon was being swallowed by a dragon during eclipses, because the wise man in the village said so 😂.
Hypothesis or a theory 🤔, if it’s a hypothesis, then you cannot call it science because no one sure if it’s true or not .. if it’s a theory then it needs to be consistent with the data AND LOGICAL.
A dragon swallowing the moon during eclipse is consistent with the data ( the mood suddenly disappears) but not LOGICAL.
Having this variety of creatures in such a short period of time with this scale because the oxygen level become higher is simply not logical to me.
WOW that was a very well done video! 👍
thanks for the vid :-)
most of the basic body forms (plus some we have since lost) appeared out of nowhere for no known reason in a little bit more than the time taken for us to diversify from our chimp ancestor - amazing! All those; complex organs, feedback loops in physiology, nervous systems etc - utterly and literally fantastic.
Well, if I understand it correctly, what emerged "suddenly", was life that FOSSILIZED well enough to be classified. We know too little about the creatures before the Cambrian to contrast it (with certainty) with what came after.
Some say the Cambrian explosion started well BEFORE the Cambrian .. extending it to maybe 50 million years (if I remember correctly)
I just cannot get enough of this evolution stuff, it’s amazing, wonderful and magical ...
Yes it is magic alright.
This is so great. I love videos like this.
Tough to study. Lack of fossilization due to hard bodies make this really tough lots of holes scientists haven’t figured out yet
LOL
Competition really drives innovation.
+joshuaoha
Send this video to Bernie Sanders please.
+joshuaoha competition between species, you knuckleheads.
m. buss
...and within species, and in economics.
+The Blind Nigga Samurai ... its just that, really, this video is about a different type of competition and a different type of evolution.
+Wissenschaftlich Bewiesen try being a little less pompous and people will respect your intelligence. Especially if you respect their beliefs.
Yeagerbomb
Do they have more videos about history? Mindblowing ö
You should provide sources in the description like links to papers and reviews
Stop spoiling Attack on titan with these videos
I wonder if the water back then was freshwater, brackish or saltwater. It could be that different concentrations of minerals and chemicals affected the creatures and it didn't matter since they have adopted to their environment.
The shape of a creature is affected by how they move and how their mate and their opponents react (social interactions).
A predator will eat their prey regardless of shells and spikes. The shells, spikes and other limbs affect how the creature expresses their aggression towards a rival and many other methods of communication towards their mate.
The size and the other augmented body parts are due to their way of obtaining food and how they move about.
Most of the creatures featured in the video resemble many microscopic creatures and vernal pond creatures of today.
I always wondered if a human went back to that time, would he be able to survive? Would the atmosphere be breathable? Is the land hostiles? Where can he find food?
@@essex3777 nope. We have smaller lungs and can't handle vast amount of oxygen
good vid. few docs on cambrian explosion and even less on the ediacren.
Fabulous Edification
I have noticed many trilobites are found in the folded posture. It seems it was a defensive posture to protect its softer under body. I have ten trilobites. Six of them are in the defensive folded posture.
Cambrian period is so cool life-form
Great thanks For this ConTENT
great content 😎
I've always viewed the cambrian explosion as an event wherein you have a vast habitat of plant life with no predation. Once levels of oxygen became enough to support sustained movement, the arms race began. But keep in mind, that virtually EVERY predatory mutation during this time was likely successful (or at least a large portion were compared to later where predatory niches are filled and competition fierce)
Wait, that only happened in the Precambrian? I didn’t realized that took so long.
Oxygen levels were higher prior to the Cambrian explosion so this doesn't make any sense. In face snowball earth was caused by Cyanobacteria removing carbon from the atmosphere, which occurred long before the Cambrian.
Wow, that's animals and stuff.
bill wurtz
But we're still in the ocean hey can we go on land?
Thank you for explaining I was so lost
why?
*THE SUN IS A DEADLY LAZER*
@@kunnoqi6054 not anymore theres a blanket
I'm glad they talk about the Avalon Period in the Ediacaran Period.
13--25 million years is sort of a 'slow motion' explosion. We often forget evolution is agonizingly long!
"Life literally exploded" _Andrew Parker_ I don't think proffessor Parker knows what the word "literally" means.
Or exploded
@@ducksmugglers lol
th-cam.com/video/TZBn8-UUQeI/w-d-xo.html
The "explosion" took 25 million years.
Professor
shhh my weebs this is history class
Great vid
Excellent, thanks,
Aot
They have no idea what CAUSED the Cambrian explosion.
Humans don't know a lot of things.
What's your point?
but they know much, and it is proven through various causal mechanisms that are trackable through re-provable feedback mechanisms that happen through constants, like chemical action. It's an insane amount of state history for extractable data, because it's stratified, or because it is retained in genetics. That's huge amounts of backing data. I don't even know why I'm saying it to you "Robert" because you're not gonna care and it's probably better that you don't. We're fucked.
Was semtex a thing back then?
Very interesting! There is some questions in earth history without the answer. But remarkably, the Economist is trying to find the answer. But of course, I have no question about. WELL DONE!
do you think the Cambrian explosion pose challenge to evoultion ?
Maybe... Of course I'm not sure. Nobody could be sure about. And I'm the kind of "detective" as Mulder from "The X Files". I love to try to find the answer on the questions on which, truly speaking, have no answer. I know, I'm the freak... What can I say? So, this time challenge to evolution! As I suppose. Because it were nothing, and suddenly - BANG! A lot of form of life. Very distressing,,,
+Tomasz Wójcik why distressing
+Hossam Eldeeb Why? Because the modern science like every religion have got the "fundamental" and "immutable" truths: And one of "most fundamental" is the evolution. Life was born in long chemistry process. And then it have been evolved from primitive bacteria to complex organisms. This process was slow and continuous. And, there is the lack of continuity. And science can not find the answer. One of most fundamental pillar of faith of science is shaking itself...
PS: I'm the Christian (Roman Catholic) in Medieval style: The Religion is the fundamental for me. I do not believe in God, but I believe to God! And the modern science is against the religion. So, I do not care about this trouble of science!
+Tomasz Wójcik science not aganist all religion but you believe in god now ?
I love the animation!
The answer to that question is : THE EDIACARIAN EXPLOSION did trigger the cambrian explosion.
I think a considerable factor in the cause of the explosion of life at the time of the Cambrian Era, is that the earth's temperature at the time is the warmest it has been since that time. Warmer than the Eocene Optimum. There is always more growth and variety in warmer times.
you know, if I turn the sound right the way to the top it almost sounds like there are people talking.
"Then, in the late Devouring period, fish became obnoxious"
I'm almost 30 & I chuckled when the narrator said anus .... * sigh *
the church people blushed and felt ashamed
Grow up. We don't need naughty language to entertain us.
Anus is an appropriate anatomical term, just like saying face, foot, knee, - go to school.
Exactly what would you almost-thirty have had him say? That aperture at one end for elimination? Almost-thirty sounds almost-ten.
Shirley Mason I make no excuses for what my idiotic baby brain finds funny. Lighten up Shirley
First they said, Cambrian explosion was a mystery, then said, what happened Exactly!
It's a mystery due to a lack of "hard", easy to find evidence. a) due to most fossils not having hard parts; and b) convective and geo-morphic removal of rock and land masses due to subduction.
@@Cyberpuppy63 there should be 1000’s more transitional fossils than there are actual fossils. I’m all for “theories” & “hypothesis” and even the word that science can’t live without namely “Chance” but the real insidious word that is always thrown around with abandon in the scientific world (and the political world for that matter) is the word “Fact”. We can’t have our cake & eat it too.
MORE VOLUME!!!
It's one of the most extraordinary events in the earth's history where the sea animals of major phyla appeared all of a sudden, the recent fossil find in China, the Qingjiang biota is yet another vivid illustration of this event that occurred 518 million years ago globally.
YAY! A documentary that wasnt uploaded by a 1993 camcorder bootleg!!
Where is the Link between cambrian explosiojn or any life, and the hard problem of conciousness?
Why? You refer to Abiogenesis, something that happened billions of years before that period and something as consciousness that happened millions of years later. In either case they have some compelling evidence.
Isn’t that the materialistic/chemical explanation ?
I mean basically, how , why and when does an hydrogen atom start to have an inner experience ?
I mean bacteria have maybe a billionth of a billionth of the conciousness we have, nothing as rich as we do, maybe the faintest sense of light or pressure.
I mean also: this complex brain activity, or any sensory experience, why is there an subjective aspect? Why is it not all happening in the dark without us having an experience ?
I mean, the matter itself is unconcious, how can it ever give rise to something as immaterial as an experience ?
I’m searching for some answers. But this video is definitely interesting and all gathered knowledge is welcome.
@@RifetOkic The total is more than the sum of its components. The brain is a collection of neurons that is so complex that it now creates the consciousness. Look at chimps, they too are aware of their existence.
They too feel compassion for other chimps.
So, even though it is mind boggling it is the result of biochemistry.
For instance, you do know that people with brain damage can loose parts of their cognition. They often can not speak or understand what you say, they can loose their empathy for others etc.
It is a wonderful thing that we are at this stage of evolution, I wonder what the far future will bring.
Millions of years ago “hey look it’s a lizard in water”
Earth “NO”
**throws oxygen at lizard**
“No your a dinosaur now”
**REEE**
.
Why is the lizard in the water
Ashley Bryant GOL 106 V1. I learned that there is much debate as to what exactly caused the Cambrian explosion with hypothesis ranging from an explosion of oxygen levels just prior to the Cambrian to a potential mass extinction prior to the Cambrian making it appear that new sorts of creatures rapidly evolved when, in fact, they had been around beforehand and just now had new ecological niches that they could fill.
Greetings all. The Cambrian explosion occurred in the eukaryotic cell based organisms, and they completely outclassed their competition (making animals, plants, fungi) leading to an evolutionary explosion. This superiority is especially visible in multi-cellular forms. This is really a story about eukaryotes “flexing their muscles” after a couple of billion years of perfecting their reproductive and maintenance control mechanisms.
The most important aspect of the eukaryotes is a cell nucleus that functions like a computing system with hardware (DNA memory system, memory system operations like reading/writing/error correction, etc.) and software (the genome). The eukaryotes had built a cellular computer sufficiently powerful to reliably construct and maintain the complexity of a multi-cellular form.
Thanks for listening.
Thank you! Glad to be an eukaryote.
;)
Interesting! I would still like to question the claim that "(...)eukaryotes had built a cellular computer system(...)".
Does anyone actually know how the information-rich molecules and the cell's information-processing system in the DNA/RNA arose?
greetings gunnar, I don't know anything about the origins of cellular computers. But I do know that wherever software systems exist in a control system, it provides the intelligence of that system. The bigger the software, the more intelligent the system. In this case, the nucleus "computer" is manufacturing a multi-cellular organism (with high level structures like organs, tissues, etc), not merely a pool of cells, like the Stromatolites (which takes little information beyond just cells to construct and maintain). In order to construct the more complex organisms, there had to be an evolution of software-size (indirectly the DNA memory system size) so that it would be big enough to solve this problem. This includes any error correction required to maintain the larger memory.
That is nice. But time is not a physical force. You need something to spur it. And you don't have Billions of years. You got maybe 20 million. As the conditions on earth for the first 3.5 billion was recovering from the formation of the moon and thick atmosphere to be stropped away. Then just at the proper conditions exist. It all just comes alive at around 600 million years ago. Mot to mention. Once you have water in all three states. You have Oxidation. Corrosion. Chlorine and Radiation. All of which would stop any cellular life from forming new features. As you get crippling mutations. That degrade the genetic information.
And yes. I know my biology. As we got better microscopes today....
Explanation: nature was high for 2 billion years
sound is quite low
Its the Cambrian explosion!
I thought the economists are only interested in economics.🤔
I guess life is a big part of economics.
I mean, without the start of life there is no economists- ;-;
@@adamplentl5588
I think economy, is an extension of biology (into the humanities)
Thank you Cambrian explosion, I am enjoying existing as a human being ! :-)
It would be nice if you could repeat that, and create thousands of new species to keep Earth Alive.
Good presentation. I felt the animated life forms were fanciful but not being an expert I can only compare some of the forms and the fossil record in texts and collections. Very stimulating.
When do Tunicates (early chordates) show up?
Aot....
Thumbnail of my mother-in-law.
So we don't know what caused the Cambrian explosion. Saved you 11 minutes.
Life literally exploded... metaphorically speaking of course.
Mind boggling and awesome do not begin to give this topic justice.
Seeking the truth as it relates to conscious life? Search *_Truth Contest_* and read the top entry called "The Present".
Matthew Chua well back in theses times I’m pretty sure sure animals were laying eggs and the male would fertilize them......not humping was done YET
Who is like me searching for a religious comment? Lol
Excellent
Excellent presentation. But what about the Eucariotic cell? And Mitochondria? Wasn't THAT the trigger?
No, it can't be that. The Eucariotic cell and the Mitochondria helped create MULTI-CELLULAR LIFEFORMS. The Cambrian Explosion was about the development of hard-bodied creatures and animals that could move on their own. Vision was created and you could fully be aware of your surroundings. Multi-cellur lifeforms appeared before the Cambrian Explosion. They were Ediacaran creatures. What you are describing was the trigger for multi-cellular lifeforms, NOT the Cambrian Explosion.
Answer: The Kree
🎼it's the Cambrian explosion🎼
Wow, that’s animals and stuff.
To sum it up, no matter how confidently we talk, none of us have any clue what happened except that it was an explosion of life forms. There are many presuppositions upon presuppositions in what we say but we hope you don't notice.
Sounds like it could be something of a "snowball" effect. Once the basic foundations are in place for competitive evolution it accelerates from there. Maybe an extinction event at the end of the Ediacaran gave enough opportunity for certain forms of animal to emerge and seed the Cambrian explosion, or one or more evolutionary innovations allowed an animal to gain a sudden upper-hand and displace the other Ediacaran biota very quickly.
I think the cause is something called *EREN JAEGAR*
ITS A CAMBRIAN EXPLOSION!!!!!!!!!!!!🎵🎵
Rock on !
This Much Quality Of a Video 7 Years Old Is Not Normal
At around 8 minutes this post talks about relationships between marine predators and their prey, and states that it has been possible to examine the stomach contents of a sea dwelling life form from 64 million years ago. Please could you explain how this data (the nature of the stomach contents) was obtained and is it available to public viewing
I believe that predation is the cause of accelerated evolution. Precambrian life would have included predatory life, albeit unconcious predation. For example, the absortion of other organisms. The absorbed species would evolve ways to defend against this, leading to hard bodies being formed. This would lead the predatory organisms to evolve ways to break those defences. Jaws for example. The whole of evolution has been an arms race.
probably because there are many different viable responses to predation, as well as many different responses to those defence mechanisms, maybe the increased oxygen specified in the video increased the top size of mass accumulation thus increasing predation and allowing for more trophic levels in between apex and producer,
i.e. morphology became the new meta.
bill wurtz brings me here
Me too...
"Wow, that's animals & stuff"
how did they reproduce tho i kinda need to find out for my school project
Uclid Sylvestre Spring 2020 GOL 106 V1: It is interesting that many approximate dates are mentioned but then statements are made about the lack of evidence to support the given theory. This just seems to confuse more than elaborate on the history of Earth and life.
Or they could pretend to a certainty they don't have.
The degree of certainty is perhaps the element you are missing here?
Did we shift realities or did the founder wipe our memories?
What about bioturbation caused by early worms? It could explain both the sudden disappearance of the Ediacaran fauna (because their niches based on microbial mats disappeared) and an increased abundance of nutrients, oxygenation of the soils and new niches needed for the Cambrian explosion. Besides, it fits the fossil data...
Yes most probably there are more than one factors causing this, but for the sake of a relatively short video these are left out.
The Ediacaran fauna largely fed on microbial mats. Their extinction is connected with the disappearance of these seafloor mats.
I did. I don't want to divulge too much, but it involves eating A LOT of sauerkraut ...
Fascinating! Well done video.
Wow that's animals & stuff
But we still in the ocean, hey can we go on land?
No
Why?
THE SUN IS A DEADLY LAZER
Divine intervention.
*WOW THATS ANIMALS AND STUFF*
Heat is also a factor, after long, gigantic ice ages, the warming of the oceans made masses of life possible...