ฝัง
- เผยแพร่เมื่อ 14 พ.ค. 2024
- Ever wonder what the very first animals were? In this video, I go over when the first animals evolved, what they were like, and what may have triggered their evolution! ;D
Link to merch site: www.geogirlscience.com/merch/
0:00 Microbial life dominated Earth history
2:32 Cambrian was NOT the first Explosion
3:44 Ediacaran Biota
5:12 Ediacaran mysteries & controversy
6:38 Were Ediacaran Biota animals?
7:59 Were Ediacaran animals related to Cambrian animals?
10:23 Comparing Ediacaran & Cambrian animals
11:56 Likely Ediacaran relationships
12:25 900 Million yr old sponges?!
14:26 What triggered animal evolution?
15:36 How viscosity led to multicellularity
18:21 Opportunities in this field!
References:
Halling et al., 2024: doi.org/10.1101/2024.02.06.57...
Potential Sponge fossil 890 Mya! doi.org/10.1038/d41586-021-02...
doi.org/10.1038/s41586-021-03...
www.ediacaran.org
Earth System History: amzn.to/3v1Iy0G
Geomicrobiology: amzn.to/2WAloTR
Ediacaran Extinction & Cambrian Explosion- doi.org/10.1016/j.tree.2018.0...
Anoxia during Ediacaran- doi.org/10.1126/sciadv.aan8983
Ediacaran Mass Extinction- doi.org/10.1098/rspb.2015.1003
Hydrogen sulfide increase in ocean during Ediacaran-Cambrian transition- doi.org/10.1038%2Fnature07072
GEO GIRL Website: www.geogirlscience.com/ (visit my website to see all my courses, shop merch, learn more about me, & donate to support the channel if you'd like!)
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Non-textbook books I recommend:
Oxygen by D. Canfield: amzn.to/3gffbCL
Brief history of Earth by A. Knoll: amzn.to/3w3hC1I
Life on young planet by A. Knoll: amzn.to/2RBMpny
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Alien Oceans by K. Hand: amzn.to/3clMx1l
Life's Engines: amzn.to/3w1Nhke
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Disclaimer: Links included in this description might be affiliate links. If you purchase a product or service with the links that I provide I may receive a small commission, but there is no additional charge to you! Thank you for supporting my channel so I can continue to provide you with free content each week! And as always, let me know your topic suggestions in the comments down below! - วิทยาศาสตร์และเทคโนโลยี
Thank you for providing these lectures for free. Your presentation makes the topic accessible without feeling cursory. I can't believe how much work goes into them. I feel like I'm getting a college education over here.
This channel should have a millions of subscribers. Even a biology-oriented guy like me has to love this stuff! Why aren't more people wanting to take advantage of this free education?
Her agw videos spook people
"Orientation?"
"Biology."
"Sex?"
"Only after the first billion years or so."
Quote
Biology oriented guy like me..
So you're simping for a chick in a video.. LoL
Next, Start sending her All your money.. cha ching.
100s of channels just like this one on YT.
@@jesusisunstoppable4438 I'm old enough to be this girl's dad, numbnuts lol
@@jesusisunstoppable4438 I'm probably older than this girl's father. I'm interested in learning, not creeping. And when so many TH-cam educators treat their audience like idiots I make sure to tell the ones who don't that they're appreciated.
Howdy Rachel, thanks for keeping this old fossil up to date. I didn’t realize how recent it’s been since the Ediacaran has been differentiated within the Precambrian. Back in my day it was Cambrian and Precambrian with suspected cellular to multicellular development without any evidence.
I’ve been thinking about a field trip to the Manzanos mountains looking for the great unconformity of snowball earth. Hope I can recognize it.
criminally underrated channel
Thank you so much! You are too kind :)
Wow. The importance of water viscosity. There’s always something new and interesting in your videos. This does seem to make complex multicellular life less likely on other planets.
Raleigh number/relative viscosity gets really weird at small scales - thrips _(really_ small insects) have brush-like wings and almost swim through the air because it's soupy at their scale.
Depends on their history. There's a reasonable argument that every photosynthetic-life-bearing planet might go through such a stage: it starts out with a significant greenhouse effect but not so hot to be uninhabitable, photosynthesisers pull CO2 out of the atmosphere, the planet cools to freezing, and a new equilibrium arises coming out of the snowball phase (possibly aided by the star growing more luminous as it ages).
It also arguably makes multicellular life in ice worlds with subsurface oceans more likely, unless life there is tightly clustered around warm spots like hydrothermal vents (which might well be the case since there'd be no photosynthesis there, but if there are nutrients to be found in colder regions, there might be multicellular life to exploit it). Although, to be fair, I'm sceptical that complex multicellular life could be supported without photosynthesis.
@@williamchamberlain2263 I am an awe watching cilia constantly beating in water - there must be so much energy involved.
@@Draxynnic it makes an iceball moon like Europa all the more intriguing. With its core being constantly kneaded by Jupiter's gravity, liquid water down deep is certainly a possibility, complete with hydrothermal vents. Finding even simple multicellular life down there would be a real eye-opener.
Snowball Earth and the earliest multicellular entities is such a good topic. ✨😊✨
I love how this channel mixes geology with biology. It's all connected.
THANK YOU! The Ediacaran is earth's most fascinating time period and there's so much more to discover.
So true! The Precambrian as a whole is my fav because of all that we still don't know yet!! ;D
THANK YOU THANK YOU THANIK YOU! I'm just starting the vid, but you liked my "WORM WARS" speculation last year (so did Scii Show), and now you're going in depth on the relevant time period, likely with the latest data. COOL! Sci Show responded to comment with an episode, but aimed at High School kids, as they do. This sounds like an updated take for undergrads, surveying recent scholarship. Yay! 🤗
No way. I just wrote a 4000 word essay on this and this video would've been so helpful
That was really fascinating Rachel! The relationship of the Ediacaran biota with later, Cambrian fauna has puzzled me too! I am of the opinion that at least some of these earlier guys were related to hard-shelled and soft-bodied animals which came shortly after because I find it odd for all of them to just go without leaving anything behind and new ones to appear without any connection to the previous...but I'm not an expert on the matter...
It would be great if you could do a video on the early evolution of chordates (as far as it is known so far) because it is pretty obvious that their last common ancestor with invertebrates lived in Precambrian times and the period of the separation and their oldest history are quite murky topics. Just imagine...it has been discovered that vertebrates are actually genetically closer to tunicates than to early chordates like Pikaia!
I graduated BSc Geol. in 1977(!), the well of geological knowledge has expanded massively since then and your vid-docs fill the gaps in my understanding marvellously - excellent narration and graphics make it a really enjoyable experience. Thank you.
Thank you so much! That means a lot ;D
@@GEOGIRL: more than deserved and I'm one of many appreciative viewers expressing similar sentiments, you really have hit the mark with this video (and several others) 😊
Thank you Dr geo girl another excellent video
Thank you for making these short lectures! I studied biology years ago, but did not study the history of life then. Became very interested in the topic later though and currently can use this information in my work. Point being these represents recent understanding and is presented in a familiar format. I'll be honest, I don't have the patience to shift through loads of academic papers (unless I have to) so being able to get recent information without having to do that is appreciated :D
If that’s what you are looking for I recommend checking Aron Ra’s “systematic classification of life”. You can find the playlist on his channel.
It’s a series of 50+ videos, each circa ten minutes long, on the various stages of life evolution in chronological order starting from unicellular life up until humans. It’s extremely well done insomuch it packs a lot of updated and accurate scientific info in a succinct and accessible format. Great resource: I have watched it several times because I wanted to have a better understanding of evolution and, ngl, with such good videos available I have become too lazy to read books.😁
I love this! i am a Nigerian cnidarian.
Thanks! Another topical video that increases my knowledge of what we know or think we know about the origin of life on earth. Thank you Dr. Phillips.
Thanks so much! ;D I am so glad you enjoyed it and learned something new :)
Cicada's. that's what.
Common Descent just did a whole podcast on cicadas 👍
Eccellent topic Rachel, thank you. I remain curious about when chemistry on Earth first became biology - I have watched a couple of Nick Lane presentations recently, and think he must be on the right track. Will we ever know how life began? Look forward to your weekly content - hope you keep it going.
It will be incredibly difficult to determine this, especially as we really still don't have a universally accepted definition of "life". Whatever happened did so over a period of millions of years and most likely involved at least one extremely unlikely event. There were most likely self-replicating short peptide strands experiencing something akin to selection pressures before RNA or membranes or metabolism. Was that life?
Nick Lane is such a good communicator! You should check his book, "The Vital Question". He is the most vocal proponent of the "metabolism first" hypothesis for the origin of life, which was first proposed by Wächtershäuser and postulates that life first arose in alkaline hydrothermal vents.
If you like this topic, you should also read about the other leading hypothesis, which is the "primordial soup" hypothesis for the origin of life.
Prof. David Deamer has written a few books on this topic.
Thanks so much! Also, I love Nick Lane!! ;D Such an inspiring science communicator :) His book about oxygen is my FAV (mainly because that was my field of research as a grad student haha) but I highly recommend for anyone who wants to better understand oxygen! ;D
Can't tell you how much I enjoy your videos. Except I just did.
Hmmm, I might need to also write a song about the pre-Cambrian Explosion. Good stuff. If you get a moment, check out my song, “Cambrian Explosion” by Paul Keller. Also, the book you recommended, Alien Oceans, was fantastic. Cheers! Paul
One of the most interesting periods in earth's history. Thank you so much for this video.
Of course! I couldn't agree more ;)
awesome video :-))))
I grew up in the Rockies, in Utah, there are some rock outcroppings with beautiful jellyfish fossils. Have a few little ones. Wish I knew who to talk to get them looked at. Would walk along the side of the road, and kick over rocks, and find them. About the size of a quarter.
Engaging presentation - good flow!
Thank you so much for doing such amazing, high quality, entertaining and educational content.
I really like the energy on which you explain stuff. How lucky must be the people that have you as their teacher.
Thank you so much for the kind words! I love getting comments like this, I feel like I should send these to my students so they come to class more 😂 ;)
fantastically fascinating! tyvm Doc.
Rachel ⚡, In your geology 💎 drip you are the bomb 💣!
This is a fantastic video. Connects a lot of dots. One trap people might fall into is thinking there's a discreet end of the Ediacaran and beginning of the Cambrian. Sort of like act one, intermission, and act two. Nothing could be further from the truth. It's a gradual transition. I believe these time periods and epochs are somewhat arbitrary. Therefore, I believe there is a gradual transition or evolution from the Ediacaran to the early Cambrian animals. It's just we can't find them yet.
This is true! And a great point! There is a discrete a transition from the Ediacaran to Cambrian when it comes to periods on the timescale, but biological evolution does not work that way, it was certainly a gradual evolution of new traits that eventually took over in what we arbitrarily deem as the Cambrian period, I think that is so important to note, thank you for saying that! I think people often get the wrong idea from the term 'explosion' ;)
@@GEOGIRL Rachel 🛶!
I think this might be another excellent video. Explaining which fossils disappeared between each period on the timescale; and how many years do the experts allow for transition between periods? Can they narrow it down to one year, one century, one million years? Thanks! Merch!
@@michaeleisenberg7867 There's actually a misconception that the so called "Cambrian explosion" somehow is an evidence against gradualism.
Actually, it looks like that because we have a loss of strata in the geological record, which, in some regions of the world, comprises many millions of years, during the Neoproterozoic Era. This is the reason why it is expected that we don't find the direct ancestors to all Cambrian phyla, even though we have actually found a few in the late Ediacaran, like the ancestors of bivalves and porifera
Periods are often bookended with extinctions, and I think I have seen evidence that there might have been one towards the end of the Ediacaran - something to do with something evolving that destroyed the Ediacaran microbial mats thereby completely upending the ecosystem. Something also seems to have made having "hard parts" particularly important around then that several phyla developed them at once.
But yes, it's pretty much guaranteed that all the Cambrian phyla had some non-mineralised late Ediacaran precursor. The only question is whether we've found those fossils or whether the similarities in appearance are convergent evolution. And on the other side of the equation, it's possible that some of the 'uniquely Ediacaran' biota did survive into the Palaeozoic, but wasn't preserved.
@@Draxynnic Thank you! I quick Google search suggests that burrowing worms ate the mats (whatever made Helminthoidichnites).
I love how detailed this show is❤️❤️❤️
Oh my favorite paleo subject matter! Ediacaran life! Most researchers consider them to be animals, perhaps having primitive versions of the Hox genes. A minority of researchers such as Retallack believe they might have been some kind of even more primitive ancestors, somewhere at the root of animals and fungi. After all, both branches share many genes and are able to produce chitin, ergosterol and other compounds. Personally I think our interpretation of Dickinsonia might be slightly incorrect. Maybe Dickinsonia was not laying flat for feeding, but was floating vertically in water, right over the microbial mats. Most quilted ediacaran organisms were stemmed organisms feeding by filtration. What if all quilted organisms were feeding the same way, and none was living as a flat disc on the microbial mat.
Amazing content! Subbed 🔥
Thanks so much! ;D
Wow. Great ideas. Thank you. 😊
Of course! So glad you enjoyed it ;D
Thanks.... I was waiting for this video.
Amazing video👏👍
Excellant graphics, as always. Facinating and fun topic. Was the appearance of multicellularity concurrent with the appearance of gamete reproduction?
I am not sure, but a quick google scholar search suggests that gamete reproduction evolved over a billion years ago in early algal species, so in algae, it was likely before snowball earth... But in animals (or animal ancestors) it may have coincided (as I am assuming sexual reproduction evolved more than once in separate lineages), but I am not sure! I hope somebody who knows more than me will respond to this thread! ;)
What a awesome video! You rock! lol
Awesome. Really well summarized. I have always (well, as long as we have known about it, which isn’t long) been fascinated by the Ediacaran biota.
It seems increasingly that the consensus is that there is less of a connection to the Cambrian, at least than it once was assumed. But then how did the Cambrian life evolve so significantly - it couldn’t have appeared from single celled organisms to trilobites in a million years. So where are their progenitors? Such an interesting puzzle.
great video, thanks
Hey are you great lady . You work hard and made video for us. I love it😍🥰
Thank you for your videos
I think life in the Proterozoic might have been a bit less strictly microbial than we often say. The Snowball probably created the kind of power vacuum needed to allow previously obscure groups like animals and such to dominate. But just because animals weren't doing much complex stuff before that doesn't mean nothing was.
I wonder if the first undifferentiated multicellular species were capable of switching back and forth between unicellularism and multicellularism as conditions required.
@@mosquitobight Like some slime moulds?
@@petersmythe6462 Yes,something like that, and maybe their descendants lost most of their unicellular phase as they became more complex.
I love talks about snowball earth yesss!! Its so otherworldly
Absolutely loved your video - liked and subscribed! Didn't like the term "evolutionary experiment" - there are no experiments in an unthinking system - would "failed evolutionary line" be better? 😊
That is a great point! I actually didn't coin the term, I have seen it used to describe the Ediacaran biota in literature, but your reasoning makes a lot of sense, I feel like failed evolutionary line is probably better ;)
@@GEOGIRL Thanks for the acknowledgment. I think that means I get 10% every time someone uses the phrase "failed evolutionary line". I'll be keeping tabs ;)
Really, all of the biosphere's history is the story of microbes. How they started out and formed larger and larger groups, until they united to create larger entities beings that could out-compete their less-coordinated rivals for resources.
It's so mind blowing that eukaryotic cells first came about 2.7BYA, and not until 600MYA did multicellularity arise. In just 600MY of multicellularity the world has got everything from bacteria to highly intelligent primates who are capable of making and sharing videos describing the actual history of our evolutionary origins. (Sorry if any of those numbers are off. I haven't checked them in a while.)
BY THE WAY. I was just talking about how crocks and birds had a common ancestor, and crocks did not evolve from dinosaurs, BUT my zoology lab manual, published this year, I think, says that yes, crocodilians DID evolve FROM dinosaurs. Has anyone else heard this anywhere?
Some sources I've seen suggests that multicellularity may have been as early as 900MYA, but that's disputed... and doesn't really change your point much.
I'd put a big "citation needed" on your lab manual. I haven't seen that idea anywhere - everything I've seen has been pretty solid on pseudosuchians (crocodiles and extinct relatives) and panaves (pterosaurs and dinosaurs) being the two big archosaur groups. There are some Triassic pseudosuchians with similar morphologies to later dinosaur groups, though, which might have caused the confusion. Or maybe it's just a part of the manual that hasn't been updated in a long time.
@@Draxynnic That's exactly what I said to my zo prof!
Did you know you can mensure bacterial species entropy level? By the influence they have on water temperature variations?
Four times higher viscosity sounds like a lot, but to put it to perspective, at room temperature dark ale has it ~2.5x higher than water already. Things like oils are orders of magnitude away, freezing water around 2x. So it'd probably be hardly perceptible to us, but at small scales ...
Geo Girl rocks! ❤🎉😊
"when you go outside, what do you notice."
Mostly that it's not the middle of Greenland.
At 12:00, in the painting on the right, what is that big weird critter that looks like a fish with 5 eyes... labelled Arthropoda?
That is called an anomalocarid! These were some of the very first animal predators! I actually have a whole video about them because they were super cool :D you can check it out here if you want -> th-cam.com/video/my2Ro4iP9pk/w-d-xo.htmlsi=KHC3oaFhmbLWOmTs
@@GEOGIRL Thank you!
Outside? I haven't unlocked that level yet.
nice video 😊
Trilobites are great, but I'm holding out for quadlobites.
I bet the ediacaran life was colorful.
Hmm, interesting, food for thought. The early bit mentioned 'decomposition'; were there bacteria around to utilise or generate the decomposition, in which case, were they part of a symbiotic relationship like mammals and gut-biome? Did they evolve in tandem with the proto life-forms, or were they part of them, like seaweed/algae etc. Just trying to dot the I's, cross the T's and fill the gaps.🤔🙂
First thing I notice? The dead hummingbird cats left on my front porch
Thank you
Hello mam I am pursuing my msc in geology from India but i had different interest for archaeology. Can you guide me whether these two fields can be combined.
Yes absolutely! You can branch into archaeology pretty seemlessly from geology! And you can absolutely work in archaeology with a geology degree :)
You learn so much more when the presenter is cute. After the ice most niches were open and everything was tried.
9:35 - Would it be accurate to say, Rachel, that your favourite arthropods are trilobites?
Insider tip - she was on the UTA geology department soccer team called....THE FIGHTING TRILOBITES!!
Finally ❤
I really appreciate these sunday morning talks. Today's was no exception. I will say, I don't think of it as our animal origins, I think of it as our DNA origins. Maybe it's just two ways of saying the samething.
Other than that, I was pretty much lost as usual. I think I'll get geology for dumby's and start from there. Lol 😆
Peace and Ahev
I was wondering what Snowball Earth was like. I imagine that over the continents, ice sheets were several kilometers thick, but over the ocean, the ice is much thinner. I was wondering if tides would break up the ice, leaving areas of frazil between ice floes. Which got me thinking, are there significant tides at the poles? Are tidal forces greater at the equator that at he poles? Maybe in conditions of Snowball Earth tidal forces would keep oceanic ice sheets broken up at the equator.
" Are tidal forces greater at the equator that at he poles?"
The FORCES not greatly.
The EFFECTS on the other hand do vary but not pole to equator.
With the current distribution of continents the tidal variation is lower near the poles .
Continental arrangement and varying ocean depths amplify and mutes the range of ocean tidal water sloshing and flows due to lunar influence.
The common bulge illustration is not rubbish exactly but more an idealised smooth surface deep water world without significant disturbance of tidal force influence.
It shows the cyclical nature but not representative of magnitude anywhere.
Some areas of equatorial ocean have very low tidal variation, similar to polar areas, but 1,000 km away there is large variation. Central North Atlantic has low range, European coast has high range.
"Maybe in conditions of Snowball Earth tidal forces would keep oceanic ice sheets broken up at the equator"
Possibly. Depending on continental arrangements and ice sheet thickness, depth of oceans under the sheets and tidal flows under them.
Ok, I thought that Dickensonia was named after Charles Dickens, for some bizarre reason. (never heard of the term before, so...) Actually it's named after some Dickenson fellah... Anyhow, thanks for the video, subscribed.
Love your content. You deserve more subs! Hopefully the Algorithm will pick you up soon 🙏
Thank you so much!
Ediacarans aka squishies!
Haha true, but not all of them! Some of them are hard, like corals ;)
We will get more stranger early finds. I'm convinced we will get some big finds. Life before oxygen proliferation, may have had to do some strange things.
I don't understand how water itself became more viscous. Do you mean the saline of the unfrozen sea became more viscous due to higher salt content?
Cold water is more viscous than warm water.
Yes, the saline leftover water became more viscous, but due to the cold temperatures not the salt content (because viscosity is temperature dependent: any liquid that gets colder gets more viscous and any liquid that gets hotter gets less viscous). It would've happened with or without the salt. ;)
Millions of years of soft serve sundaes before Gaea invented cones.
❤❤❤
Kind the biota that would fit europa's moons and ❄ ❄ moons with heating oceans underneath
Wait, you have trilobites on shirts you do not own?
You Rock.
The real important question is what color bucket hat should I get?
That's a tough question! haha I have the green one and love it :)
hi. How cyanobacteria survived the Earth snowball ?
It's likely since cyanobacteria lived in microbial mats (layers of different microbial communities that provided each other nutrients), they didn't have the same degree of difficulty as other microbial organisms that didn't live in community mats because these mats are essentially multicellular organisms (even though they are made up of single-celled organisms) since their communities of microbes mutually benefit each other by providing each other nutrients :)
If it's true that Snowball Earth triggered multicellularity then without that event Earth today would be the same as it'd always been: single celled life and that's all.
I'm not completely close minded... I'll think long and hard over what you say 😊
I’d like to propose the coining of a new term: “discovery bias”. I think (more in the past than now) people have not considered different types of life, or body plans, or well, anything, because we can’t find them with their inability to fossilize.
Probably a subset of survivor bias.
I honestly believe all sciences are the next step in human evolution are planet is lovely but colonizing an learn how to master space would help break through alot of the current unanswerable questions we have in all are frontier of sciences science means to know an if we can compare the geology of other worlds i believe it will help us understand are own planet an how biology behaves if we find life on other worlds i guarantee people will flood your classrooms trying to learn the craft an push are species to the next level
One of those species back then was our direct ancestors, tracing back down our lineage.
Convergent evolution, like steak knives for teeth and powerful crushing jaws... once it grabs you that's it! Like crocs! Rex could probably death roll
Diversity doesn't happen when things slow down... it's when it speeds up that things take off... leading me back to the sun!
Ediacaran biota looks like animal plants! They look like plants, but they are actually animals!
Aren't stromatolite mats multicellular? And, aren't the Cnidarians and Ediacaran similar to Stromatolite?
Stromatolites are just mats (or stacked layers) of single-celled microbial communities ;) So, they contain multiple cells, but are made up up unicellular organisms. I think you may be thinking of stromatoporoids, which are an ancient reef-building organism that is extinct now; these were potentially more closely related to phyla like porifera (sponges) and cnidaria (corals). :)
@@GEOGIRL well, I'm glad I brought it up!
@@GEOGIRL I'm re-reading Horace Judson's "Eighth Day of Creation" to re-find a quote. I went through a blog of mine to put all the quotes into one ebook, and I've lost track of this one quote. Well, I found this one remark from James Watson(of DNA fame),
He said that one should be at least partially unemployed to do great things. I thought this was interesting in light of a conversation we had about getting a Phd, and doing Phd research. That doing research under Phd, or even being a Phd and being paid for research for a certain amount of time is to restrictive.
Wel, I thought this was interesting as confirming my feelings about it. I could not have made my book on a one or two year paid leave program for being a Phd!
Observing bacterial, fungi colonies is easy to imagine they jumping to this state by having open enviroment insted of petri dish and no predators! I bet the salinity and stable (low entropy) and crystal like (hard shells) jump all bacteria into multi cellular system's
In the book The Sixth Extinction, the author states that conditions on Earth have been beneficial for complex multicellular life for 750 million years, and these conditions will disappear in 750 million years. So, intelligent life emerged exactly in the middle of that period. That leaves us a lot of time to figure out future climate changes, what we can and cannot do to keep life going, and how we can (and should) save our ecosystems and carry them with us if we move away from Earth someday.
Has there ever been evidence of a species diverging and then merging back together?
TRILOBITES….
YES!
Hy G chick,who slimed the water?😄
Get the ads with this channel.
Did snowball Earth force animal evolution? That's like asking is the Pope catholic, it's a sure bet that that climatic effect had a profound influence on animal evolution.
Snowball Enceladus
The Phanerozoic should begin with the Ediacaran period, not the Cambrian period.
That's a gneiss chert
Sadly, that shirt isn't going to look NEARLY as good on me as it does on you.
I seem to have annoying misspelt sub-titles again. Who ever typed them out needs sacking and replaced by someone with a basic grasp of Zoology. For example Nigeria doesn't date back to the Ediacaran Biota but Cnidaria might! And what is the Canan Explosion!
Sorry about that, I currently use the auto-generated subtitle feature that TH-cam offers because I don't have time to write them out or hire someone to do that yet, but I hope someday I will! In the meantime, I apologize!
If you want to be as cool as me 😮
LESS FLOWY ?????? lmaorotf !!!!!!!!!!!!
Nobody likes what I say about rex.... but at least I'm trying to put it in a realistic perspective... damned thing waits for food to come to it! Most likely by the water hole!
Lol can't wait for fireball earth
Impossible, with all the foliage and rock's and bushes and trees how could rex hunt in that? Most of what is said about rex needs rethinking
I'm understanding that radiation causes mutation... the sun itself is responsible for evolution!
Trees were here 69 million years ago...a bus sized nothing is running in my woods... just saying