Evolution of Eukaryotes- How & Why Endosymbiosis Occurred & When First Eukaryotes Evolved | GEO GIRL

[@GEOGIRL]

Lol, I was watching this back and realized that I mispoke about cyanobacteria, they are not the *only* things to have ever evolved the ability to convert light energy to chemical energy (photosynthesize), there are other prokaryotes that photosynthesize. Can't believe I have a whole video about the various photosynthesizers but I missed this mistake hahaha! Sorry about that, hope you enjoy the video! ;D

[@godlessrecovery8880]

This channel is really growing. I'm glad for her. She's making great Content, always well researched and presented. Congrats to you Geo Girl

[@GEOGIRL]

You are too sweet for saying this, thank you! And thanks for your continued support, I love that when I grow, you feel happy for me, I have the best youtube community ;D

[@tedetienne7639]

Excellent video! I'm learning so much from each of these discussions. I'm so happy to have just joined as a channel member!

[@GEOGIRL]

So glad to hear that you've learned a lot from my videos, and also so grateful that you've signed up to be a member, thank you so much! I am so sorry I haven't been posting much member's content lately, this summer is crazy busy for me, but I promise I will post much more in the fall. ;)

[@stephankeller2301]

As always: amazing :)

[@GEOGIRL]

Thank you! ;D

[@chaiwarrior11]

Biggest step to complex life, as far as we know! Good chance there is a lot of life in the universe, but that filter and time to pass it, may be the explanation for the Fermi paradox.

[@LuisAlvarez-id9qy]

This is such an incredible channel! I have you on in the background while I am working :).

[@GEOGIRL]

So glad to hear that! Thank you😊

[@ellenmcgowen]

Thank you for mentioning the hydrogen hypothesis, which I had not heard about. I did not know that alternatives to the phagocytosis hypothesis had been developed and I like the idea that a symbiosis between a methanogen and a eubacteria might be the starting point for evolving eukarya.

[@bobdobbs943]

Might be the starting point isnt science or facts.

[@Smilo-the-Sabertooth]

Oh the excitement I feel when receiving the notification that you have uploaded a new video, always a great start to my day. Thank you very much for another absolutely fascinating topic and incredibly interesting video. As usual, it’s always such a tremendous pleasure for me to be learning with you my favorite teacher. I’m always looking forward to more of your always outstanding and never disappointing videos because you always make the best content. You’re truly the best, my friend. 😊❤😉👍

[@GEOGIRL]

Thank you so much for the uplifting comment! i am so happy you enjoyed this topic, I know it isn't a super popular topic since it gets kind of biological and chemical rather than geological, but I think it's still really important when discussing Earth's history and making sense of the rock record :D

[@GEOGIRL]

@E Van He actually has a pretty cool YT channel where he tours muesems and state parks and stuff right here in the US, you should check it out ;)

[@Smilo-the-Sabertooth]

@@GEOGIRL You’re very welcome my friend. And very true, sometimes it takes certain topics to help us gain a better understanding about other topics, the more we learn, the better we understand. And whether it’s geology, biology or chemistry, it’s all very interesting to me. We learn something new every day.

[@Smilo-the-Sabertooth]

@@GEOGIRL And thank you for your always kind and friendly replies that I always appreciate very much. They always heal my days that could’ve been better. I hope you had a wonderful day.

[@GEOGIRL]

@@Smilo-the-Sabertooth Diddo! Hope you have a wonderful day/evening as well! Thanks friend ;)

[@donaldbrizzolara7720]

Well executed and thought provoking discussion. Thank you Rachel.

[@GEOGIRL]

Thanks Don! Glad you enjoyed it :D

[@oker59]

I've often had this thought that the herbivores and carnivores, and even the birds taking seeds around to distant islands were eco-system likeI(single cells are also like mini eco-systems; they work to preserve some ancient ecoystem . . . the inside of the cell is kept at a certain temperature and the right elements are kept at the right levels). The whole herbivore/carnivore is another way to move nutrients around, and keep the ecological cycles going! I use to know the chemical formula for photosynthesis; and it just seemed to me that the herbivore/carnivore is somehow a higher level manifestation of the photo-synthesis/fermentation thing. The symbiosis of mitochondria/chloroplasts seems to me to prove these ideas!

[@micheal49]

Pft! We're all just the peptides way of making more peptides.

[@georgestewart9001]

this is a very good video i like this video alot its your best video i have seen by far thankyou for a real good video

[@GEOGIRL]

Thanks so much! So glad you enjoyed it :D

[@kwinter2541]

Your laugh at the beginning is adorable . That·s really cool stuff . Lichen developed the same way , by algal structures incorporating cyanobacteria into little cups as symbionts . So , in a way... we·re all just really complex plants . That·s my theory .

[@JoesFirewoodVideos]

I played a lot of PAC-MAN in my youth. I ❤️ GEO GIRL

[@unstoppableExodia]

Eukaryotes, i carry oats, we all carry oats. And then we get to eat those oats, Hooray !!!

[@PhilipSalen]

You are an amazing lecturer. This is one of the most interesting topics in cellular biology.

[@caspasesumo]

Great and thought-provoking video (as usual )! It is sometomes surmised that Mitochondria originated before chloroplasts because the endosymbiotic event that generated mitochondria must have happened early in the history of eukaryotes since all eukaryotes have them. However, if one goes by the Oxygen detoxification function of Mitos, does it make sense that you cant evolve a chloroplast unless you already have a mito, making all early Chloroplast endosymbiotic attempts futile and/or lethal? What does the fossil recird say about this?

[@GEOGIRL]

Oxygen detoxification refers to the detoxification of radical and reactive oxygen species, not O2 like the air we breath and the product of photosynthesis, and it's is actually through respiration that these harmful oxygen species are formed, which is why these detoxification mechansims evolved in mitochondria rather than chloroplasts so that O2 respirers had these abilities and were not intoxicated by their own metabolic byproducts. I don't think tis function in mitochondria would've affected chloroplast function or development... But please correct me if I am misunderstanding this, it's a very interesting thought! :)

[@noitalfed]

Thanks!

[@GEOGIRL]

Thank you! So glad you enjoyed this video, it's one I loved making because I thought the topic was just so cool! :D

[@Hellbender8574]

Great video. I'd like to learn more about what eukaryotes don't have mitochondria and why!

[@GEOGIRL]

I know right! I was surprised to learn that those were out there, but also not surprised because life is pretty crazy sometimes haha ;D

[@theobserver9131]

"She blinded me with science!" How chemistry turns into life gives me goosebumps!

[@uncleanunicorn4571]

The big takeaway is that organisms can elevate each other by mutual exchange and collaboration. Nature red-in-tooth-and-claw isn't always the only way.

[@TheRexisFern]

I care e-yote, you care e-yote, we all care e-yote. ❤

[@GEOGIRL]

😂lol love this!

[@EricaMZDM]

...I want a periodic table duvet cover

[@Beastclub679]

Hii gio girl .. very nice content..👌👌 very useful..👍👍

[@GEOGIRL]

Thank you ;)

[@Beastclub679]

@@GEOGIRL most welcome..😇😇😁

[@punditgi]

Smart people evolve towards watching videos from Geo Girl! 🎉😊

[@matthewmorgan9269]

Outstanding !

[@geraldfrost4710]

In anger I said to someone, "You're a eukaryote!" The gear-stripping confusion was worth the arguement. "I hate crawling under the house to fix the plumbing. Crawling through cat poop, mouse poop, spider webs, flees, and nematodes. It's soooo gross!"

[@davidniemi6553]

Very clear explanation of some really important events in our past. Thanks. Really makes me very curious about what was going on right before, and during, the Cryogenian that helped set the stage for the Ediacaran and beyond.

[@thhseeking]

I loved the cameo by your owner :P

[@curtisblake261]

What I learned in college times a million.

[@TheChuckwagonLite]

What are rocks during the hadean period like?

[@GEOGIRL]

Ultramafic komatites to mafic basalts (very homogenized, dense material due to the short amount of time that Earth has been differentiating by then).

[@TheChuckwagonLite]

@@GEOGIRL I didn't understand any of that, but I'm sure it's cool

[@TheChuckwagonLite]

@@GEOGIRL pun intended

[@platzhirsch4275]

A major scientific problem with the endosymbiosis hypothesis is that as soon as the theory first appeared it was (and still remains) untestable, as I wrote below. The problem is endosymbiosis proposes no real mechanism and most textbooks show the simplistic picture of a cell that swallows another cell that becomes a mitochondrion or here a "packman". Actually, it is now far less plausible than when first proposed because a great deal more is known today about organelles (e.g. mitochondria) and bacteria. Our understanding of the biochemistry of organelles today should make us doubt such postulates as its pure fantasy. Among the other basic problems with the theory are: What prevented the host cell from digesting the invading organism? and: Where did the many other structures required for a eukaryotic cell to survive come from? For example, microtubules are not explained by the theory, even though they are needed for cell division and motility in eukaryotic cells. De Duve notes that nothing is known about the evolution of the cell cytoskeleton system, which requires many new innovations to function. Similar lines of evidence cited to support the theory that spirochete bacteria gave rise to flagella are problematic. Tubulin, the primary component of microtubules in eukaryotic cells, has not been found in any prokaryote. For these reasons, most evolutionary biologists reject the idea that flagella, tubulin and most other cellular structures originated by endosymbiosis. Adding biochemical analysis the task gets impossible. At best, endosymbiosis explains the origin of one or two organelles. But for a eukaryotic cell to function, a whole new set of structures is required, all of which must evolve concurrently for functional integrity. Contrary to the endosymbiotic theory mammalian mitochondrial ribosomes, and the amino acid sequences that produce the ribosome, are completely different from the corresponding features in prokaryotes. Mitochondrial ribosomes are in fact so different from bacterial ribosomes that they are designated as the mitoribosome. When endosymbiosis was first proposed, it was assumed that ribosomes existed in only two forms, a smaller 70S variety used in prokaryotes, and a larger 80S ribosome used in eukaryotes. The S in 70S refers to the unit in which the sedimentation factor is expressed. The sedimentation coefficient measures basic morphological differences, a quantity related to the size of the particle which is equal to the terminal outward velocity of the particle when centrifuged in a standard fluid medium divided by the centrifugal force acting on it. I do think youre aware of this. The ribosomes used in mammalian mitochondria were expected to resemble the prokaryotic 70S ribosome because they were similar in size. Instead, researchers found that Mammalian mitochondrial ribosomes (55S) differ unexpectedly from bacterial (70S) and cytoplasmic ribosomes (80S), as well as other kinds of mitochondrial ribosomes. Mitochondria employ a system required to manufacture proteins that is also very different from bacteria. Mitochondrial ribosomes called mitoribosomes are described as ‘undersized’, mini-ribosomes having mini-RNA polymerase, and even mini-DNA. Mitoribosomes differ from prokaryote ribosomes in RNA, protein content, and position/function of the ribosome parts, and are significantly different in DNA sequence (especially regions that do not contact the tRNA or growing polypeptide chain). Unique features of the mitochondrial ribosome include novel mRNAs that process mitochondrial mRNA and a novel guanosine triphosphate (GTP) binding site used during polypeptide elongation. Other contrasts between bacterial ribosomes and mitoribosomes include many basic construction and assembly differences. Proteins comprise a larger portion of mitoribosomes than prokaryotic ribosomes. Some of these proteins are in novel positions and have functions different from the prokaryotic ribosome. One of many examples includes the 55S mitoribosome, which is held together by 15 intersubunit bridges and only six of these bridges are similar to those employed in prokaryotes. Furthermore, 33 of the 81 proteins identified so far in human mitoribosomes have no homologues in prokaryotic ribosomes. These examples of the many differences between the prokaryotic and mitochondrial ribosome further illustrate the chasm between the two ribosomes. More examples could be documented and undoubtedly more will be discovered with further research, which we are currently undertaking. The summary of it all however unless your video doesn't have the claim of being scientific i feel uncomfortable it ignoring major issues thus creating a complete wrong impression, I'm afraid.

[@platzhirsch4275]

Adding to my summary below the common endosymbiosis scenario does truly postulates that free-living eukaryotic cells eventually joined in communities now called multicellular organisms but we should add its a hypothesis. It too doesnt stand critical analysis. Problems were encountered soon after the endosymbiosis theory was proposed. For example, further research found that the mitochondria of fungi, plants, and animals were so different that endosymbiosis must have occurred independently many times, which only multiplies the highly improbable odds of the endosymbiotic scenario occurring even once. The odds against it again astronomical. It was predicted that mitochondrial DNA will be different from nuclear DNA, but instead will consist of admixtures of sequences from eubacterial and archaeal genes. However the mitochondria were found to possess DNA independent of nuclear DNA. Another important factor supporting endosymbiosis was the discovery of plastid DNA (cpDNA) in the chloroplast of plants called the plastome, which supporters argued made the endosymbiosis mechanism for the origin of organelles more plausible. The organelles called mitochondria are commonly believed to have arisen only once in evolutionary history, but despite their common ancestry, mitochondrial DNAs vary extensively throughout eukaryotes in genome architecture and gene content. Researchers have found that the largest mtDNA is in a freshwater protozoan, Reclinomonas americana, which has 69,034 nucleotides and 97 genes that encode 67 proteins, which includes at least 18 proteins not previously known to be encoded in mitochondria. Endosymbiosis must, therefore, postulate that the engulfed bacteria lost 96-99% of their proteins, from ~1,600 down to below 67, depending on the specific engulfed protobacterium. For humans, only 37 genes are essential for cellular respiration. Minor knowledge of biochemistry/ amino acid sequencing and DNA should exclude the possibility of the becoming any favourable theory. In short, these few examples illustrate the chasm existing between bacterial DNA and mtDNA which is only one of many problems with endosymbiosis. The endosymbiotic theory relies heavily on homology between organelles and bacteria. For example, each mitochondrion has a circular genome like bacteria, but much smaller and lacking histone proteins. The mtDNA is usually located in the mitochondrion’s matrix, although it is sometimes attached to the inner mitochondrial membrane. Mitochondria also closely resemble purple-aerobic bacteria in size and shape. They both use oxygen in ATP production using the Krebs cycle. Certain antibiotics that kill bacteria also inhibit mitochondrial functions. These general similarities alone do not demonstrate endosymbiosis because many significant, often major and critical, differences exist. One factor arguing for endosymbiosis is membrane composition. The outer membrane of both chloroplasts and mitochondria has both structural and chemical similarities to the prokaryotic cell membrane. Later research, though, determined that mitochondrial membranes are only superficially similar to prokaryotic cell membranes. One difference is that the proteobacterium alleged to have entered the protoeukaryote would have had a single membrane, whereas modern mitochondria have a double (inner and outer) membrane. The double membrane is not optional, but critical for its function to charge ADP. The inner membrane contains numerous plate-like folds called cristae that possess membranous sacks containing enzymes. Cristae can be either exclusively lamellar or exclusively tubular, but some mitochondria contain both types. Another difference is that the mitochondrial inner membrane has a different chemical composition from that of prokaryotes but is the same as in eukaryotes-contrary to the endosymbiosis theory’s prediction.

[@robertab929]

Check these papers: * "An excavate root for the eukaryote tree of life" (2023) * "An Alternative Root for the Eukaryote Tree of Life" (2014) You will see a lot of explanation about variation of mitochondria in Eukaryotes.

[@chrisstargazer5866]

Good stuff

[@nickb-whistler4431]

You inspired another poem! Thanks for your amazing videos! The Stories of Multiverses Encircling the Godgrove and its Nine Trees of Life Loki built the burning rainbow bridge called Bifrost In order to unite Divine Tribes of the Gods, But crossings worked both ways like Chaos, bridging Strife. - Excerpt from the Saga of Ash and Ashes 2.1 billion years ago, in cold seas, An Asgard Archaean swallowed a smaller Aerobic Bacterium that had swum inside, Encircling one uni-verse in another one; From this pair-united, Multicellular Life Came to be in the lowest of keys and the deeps Of Earth’s seas, unlocking Verses of Elder Flame. In this divine union between Kingdoms of Life, Lokiarchaeota discovered Animus-Mind of God, Gift of Flame, joining Songs of Elders in the seas; Taking Euphonia-Perfect Sound-for her name, She was crowned Arch-Queen of Archaeans And all Eukaryotic tribes who came after, Assuming power to write, re-write, and erase. The small bacterium inside Euphonia Lost function on its own over rhyme-cursing bonds, But it gained safety in the larger bodied host, Becoming a powerhouse in the cell, known to most As Mitochondria; still, it kept code and Verse To itself, replicating its parts into new DNA, separate from codes of its gracious host. In this way, Mitochondrial DNA traced Its origins in long ancestral lines through ages, Becoming as a House in a House, or a Verse In a Verse, conceiving Prince Parallelism, Patron God of Corresponding Echoes in Song, Who oversaw endosymbiotic meter And the bridging of Kingdoms of Life in the Tree. 500 million years later, another Multi-verse came to be closer to Goddess Sol Protected by Water from UV rays of Death; Although Prokaryotes still dominated the seas, Eukaryotes had grown large and wide-spread across Waves, roaming and grazing on smaller living things, Such as Cyanobacteria, who praised Sol. A distant descendant of the first Multi-Verse Engulfed a smaller Cyanobacterium, Who became a house-guest in the cell and worked well Inside for both of them; over time, the blue-green Bacterium became dependent on its host, Losing autonomy but growing rich at last, Forming a House in a House, known as Chloroplast. Chloroplasts kept and copied their own code Even as they lost autonomy as tenants- Imprisoned in a cell, paying rent by turning Light into sugar and resources for its Lord; This system of Foodalism proved successful (However foolish it might have sounded at first); By the end, Chloroplasts became a household name.

[@robertab929]

Steranes in rocks 2.7 Ga might be contamination. Check also paper: "Evolution of bacterial steroid biosynthesis and its impact on eukaryogenesis" (2021)

[@princeshukla7661]

Beautiful black cat🐈

[@Beastclub679]

White cat..😅

[@princeshukla7661]

@@Beastclub679 look in first 10 second of this video

[@GEOGIRL]

Haha, she is neither black nor white. At the beginning of the video she looks black in that lighting, but she is actually a tortoise shell pattern :) and thank you, I would tell her you said she was pretty, but I am afraid that would go to her head hahaha

[@jastermereel4946]

and lots of eukaryotes have symbiotic algae, not to mention the whole microbiome thing. it can be hard to tell where individuals end and the ecosystem begins, everything is connected down to the tiniest level.

[@velikerimov9703]

Hello My dear GeoGirl, where is my Clay Minerals videoo😃😃😃

[@GEOGIRL]

Hi Veli! I am so sorry, I haven't done it because I don't have a good reference about clays, none of my books talk much about clay. Do you know of any good papers, articles or books about clay minerals. Or do you have a particular aspect of clays in mind, because that would help to narrow down my search. For example, would you rather a video about the physical properties of clay minerals or the chemical properties? Would you rather me discuss microbe - clay interactions or clay minerals in abiotic systems? In other words, what context would you like me to discuss clays? Thanks!

[@velikerimov9703]

@@GEOGIRL hello, yes i have pdf files and other books about clay minerals, only these are in turkish and russian, I request you to make a comprehensive video about clay minerals, because I am watching your videos and I like it very much, you can find english books called (clay mineralogy) on the internet, for example pdf drive You can find chok books on the site

[@velikerimov9703]

@@GEOGIRL If you want, I can find books and send them to you, general information about the clays I want from you, about the mineral variants their structures and textures, they may also have pictures under the electron microscope. SINCERELY, Love you. Good luck Geo Girl

[@GEOGIRL]

​@@velikerimov9703 Ahhh, that clears it up for me quite a bit when you say clay mineralogy, textures, structures, etc. because now I know what realm or field you are aiming for. I will look for a clay mineralogy book and hopefully get it soon so I can start learning about it (but I can't promise that the video will be very soon since I need to get familiar with the subject first) My goal is by end of summer here (so around september, I hope that's ok)

[@velikerimov9703]

@@GEOGIRL Ok, Geo Girl i am waiting,Thank you very much, have a nice day

[@nomdeguerre7265]

Did the process involve ingestion, or invasion...or both?

[@supernovaleftover1812]

When my faith in humanity wanes I seek out peope like yourself, who rekindle my love for existence. What lucky creatures we are, with our unique ability to try understand the univere that created us.

[@GEOGIRL]

Wow this is probably the nicest comment I have ever gotten! I am so glad that my videos retore your faith in humanity! Along with teaching, I also just like to spread positive energy, so this comment made me very happy ;) Thank you!

[@princeshukla7661]

Hello geo girl

[@platzhirsch4275]

Lastly i would like to add that organelles are very complex structures, consisting of multi-thousands of smaller complex parts. A cell cannot survive without ribosomes, each of which contains thousands or even tens of thousands of molecules, each one of which must be assembled to exacting specifications. The biochemical nature of ribosomes blow the mind of any serious scientist. The interaction between the ribosome and the cells DNA is far more advanced than any software available today. All this must work together. Cellular life is impossible until all of its necessary parts are manufactured and properly assembled. DNA without a cell has no physiologic meaning. Few scientists have even endeavoured to speculate on the details of the transitional forms between the hypothetical pre-organelles, let alone present evidence for the multi-thousands of transitional forms required to create a reasonable scenario that could bridge the free-living cells and the cells with organelles used in multicellular organisms. Its all just fiction and fantasy. I think we should be honest about this. Then we see a transport system in the cell, as you will know. Gated transport requires construction of a door between the cytoplasm and the nuclear membrane and a chemical sensor (a protein that has the correct identification tag). When the protein package approaches the sensor, it opens the gate, allowing the protein to pass through. This control mechanism requires the protein to have the proper identification tag and a gate programmed to open in response. The gate itself also contains many parts, thus introducing another level of irreducible complexity, i term often avoided, but maybe indeed necessary. Each of these gated transport components is complex and consists of thousands of parts at the molecular level, all of which must exist for the gated transport system to function. The vesicular transport system also uses a set of specially designed sensors. But instead of a gate, the proper identification tag causes the compartment membrane to bulge outward, pinching off and forming a vesicle that totally surrounds the protein. The transport vesicle then travels to a destination predetermined by its identification tag. If the vesicle tag and identification sensor match, another sensor recognizes the vesicle, and it merges with the compartment. Then, the pinching-off process is reversed to allow the proteins to be carried inside the new compartment. The almost certainly irreducible complexity of the system must include two complex sensor systems, two identification tags as well as the vessel itself. At a level beyond this, each sensor identification tag and the carrier vessels are, at the molecular level, likewise constructed from thousands of parts, each of which is also likely an example of irreducible complexity, a term we should not avoid. The vesicle must contain all of the structures that allow it to bud off from the original compartment and then to unite with another compartment. And all this is controlled by DNA, where did that kind of highly advanced biochemical engineering information come from? I know colleges after understanding this started believing in God. That's how mind-blowing it is. Knowing this its hard to look at a very casual summary like this as it gives a very false impression.... as much as your effort is honoured. Thank you for giving me the chance to humbly add these thoughts.

[@robertab929]

Read about Asgard cellular metabolism, especially members of Hodarchaeales (similarities in cytoskeleton, N-glycosylation, GTPases, facultative aerobes, etc). Eukaryotes have so many similarities to them.

[@platzhirsch4275]

​@@robertab929 I don't understand your comment. Why write a comment asking someone to read something? The comment section is there for writing your opinion on a given topic. You however don't do that. There's lots of Literature on all sorts of viewpoints our there, even claiming the earth is flat.

[@ricktownend9144]

Thank you for so clearly explaining the zoo-park that is a living cell ... who needs dinosaurs?

[@GEOGIRL]

That's what I'm saying! ;D

[@oker59]

One book I found on my father's shelves was Isaac Asimov's "Extraterrestrial Civilizations." It's the original "Rare Earth Hypothesis" book. The authors of the Rare Earth Hypothesis book didn't know of it; but, I think I finally was able to contact them a few years ago; but anyways . .. Well, I've always been struck by some improbabilities in both biology and human history. If Mars orbit wasn't off, would Kepler have come up with his equal areas law? And would anybody have bothered to develop Physics and Astronomy beyond Copernicus? There's a whole bunch of these, and in terms of Biology, here, It looks like historical events came out that allowed single cells to evolve into multicellular; if these historical things didn't happen, life would not have bothered evolving multicellularity! If life didn't evolve multicellularity out of historical chance, or maybe the host planet was blown away by a nearby supernnova, then Intelligent life(whatever that is) wouldn't have developed!

[@GEOGIRL]

What cool thoughts and questions. See I think it still would have evolved because given enough energy (O2 and sunlight) and time, eukaroyotic cells and multicellularity (just like the first life on Earth) was bound to evolve. Most likely, multicellular organisms attempted to evolve multiple times before it stuck (just like with the first life on Earth, which is why we call it the last universal common ancestor, LUCA, rather than the first, because there were multiple attempts). If the conditions weren't just right the first time, then a million years goes by and it trys again, and so on until the conditions are just right. And when I say 'trys' i mean random mutations and parasitism events, but eventually the randomness turns into order because as soon as the first eukaryote reaps the energetic benefits and passes them down to later generations those organisms flurish over other less energetically able organisms. But who knows, maybe you are right about the multicellularity and it would've have 'tried again' and instead Earth would be home to a world of bacteria just like 3 billion years ago!!! How cool would that have been! Haha, this is so fun to contemplate! :D

[@oker59]

@@GEOGIRL Hi Geo Girl - I think the idea that life could have arose multiple times around the Earth is interesting. Could there have been life with different dna? Or maybe silicon life?

[@oker59]

Ope, forgot to mention - I've read a couel of books, either by Lynn Margulis, or about her work - the Gaia hypothesis which she contributed to. I read her "What is life" I'm tempted to say I should re-read it, after taking a few Bio classes, and going through some great youtubes like yours and others(there's an Aron Ra who did a 48 videos of the history of life) and Symbiotic Planet.

[@GEOGIRL]

@@oker59 Great question! I think there could've been different variations of early informational molecules, but no, I don't think any could've been silicon based on Earth (the temp and pressure conditions don't allow for that on Earth, even early Earth), they would've all been C based, but just differed slightly in molecular structure most likely.

[@Tk1NE]

Heaven on Earth Geogirl and Veronica Clark of Citi on Bloomberg. What else could a man want. Brains and Beauty double.

[@erictaylor5462]

Hey, don't eat me and I'll do you a favor! But already ate you. Okay, don't digest me and I'll do you a favor. And they lived happily ever after.

[@robertab929]

Evolution did not happened instantly. There was a lot of steps in which organisms evolved. Evolution of Eukaryota on molecular and cellular level took place in Paleoproterozoic, Mesoproterozoic and first half of Neoproterozoic until first animals evolved. Imagine time needed for evolution of each molecular pathway, all major proteins and mechanisms important for cell contact, cell communication, cell signaling... Holozoa, Filozoa, Choanozoa, Animala - each new group (step of evolution) had a innovation making them closer to animals. Choanozoa developed most proteins needed for multicellularity, you can check the biology of members of Choanoflagelata (sometimes they are as single cells, sometimes as multicellular organisms). Animals are just next step - they are multicellular, only gamets are single cells. Animals (Metazoa) evolved probably before Cryogenian/Ediacaran, somewhere 700-900 Ma. Major groups of Metazoa appeared in second half of neoprotezoic. Earlier appeared Choanozoa, Holozoa. Opisthokonta evolved approx. 1300 Ma, Amorphea - ~1900 Ma, etc. Groups like Diaphoretickes, TSAR, SAR, Stramenopila, Alveolata, Rhizaria, Viridiplantae, Glaucophyta, Rhodophyta, Cryptista were appearing in paleoprotezoic + mesoprotezoic. See these works: Strassert+ (2021) A molecular timescale for eukaryote evolution with implications for the origin of red algal-derived plastids Jewari & Baldauf (2023) An excavate root for the eukaryote tree of life

[@Miloun]

Nice cat btw.

[@frankkolmann4801]

I thought I knew a bit of science. But all the big sciencey words just make my head spin.

[@mdb1239]

Life starting from natural processes is impossible. Once life has begun then it is resilient and tenacious, but life stating from natural processes is impossible. Not only that but the first life on Earth according to fossil records is photosynthetic. Photosynthesis is one of the most complicated processes (maybe THE most complicated process) in nature.

[@aidenmartin6674]

Actually the first known life was anaerobic bacteria, some of which later evolved into Cyanobacteria

[@mdb1239]

@@aidenmartin6674 And your evidence is what? Conjecture? Guess? The fossil evidence from the oldest rocks (4.2 billion year old rocks) show oxygen producing life existed on Earth. We have fossil evidence for cyanobacteria from 3.7 billion years ago producing oxygen.

[@aidenmartin6674]

@@mdb1239 you can find out by looking it up. The primitive anaerobes came before the more specialized Cyanobacteria. Here it says through gene analysis they found that the ancestors of what would become Cyanobacteria separated from other bacteria 3.4 billion years ago. After they separated from the other bacteria then they gained the ability to photosynthesize. Relevant part marked with ** Title: Zeroing in on the origins of Earth’s “single most important evolutionary innovation” Now, MIT scientists have a precise estimate for when cyanobacteria, and oxygenic photosynthesis, first originated. Their results appear today in the Proceedings of the Royal Society B. They developed a new gene-analyzing technique that shows that all the species of cyanobacteria living today can be traced back to a common ancestor that evolved around 2.9 billion years ago. **They also found that the ancestors of cyanobacteria branched off from other bacteria around 3.4 billion years ago**, with oxygenic photosynthesis likely evolving during the intervening half-billion years, during the Archean Eon.

[@mdb1239]

@@aidenmartin6674 BUT we have fossil evidence of cyanobacteria stromatolites from 3.7 billion year old rocks. Who cares about hypothetical gene ESTIMATES (from MIT). Irrelevant. We have fossil rock evidence. That means photosynthetic life existed before 3.7 billion years ago and we have evidence of hematite (iron rust in water) from the oldest rocks on Earth from 4.2 billion years ago. There was enough oxygen being produced on Earth to saturate water to rust dissolved iron. Evidence vs. ESTIMATES.

[@aidenmartin6674]

@@mdb1239 just because there were Cyanobacteria a long time ago does not mean they did not evolve from more primitive life that came before them. Where is your proof that there wasn’t more primitive life before the Cyanobacteria, that they came first and anaerobes second.

[@bobdobbs943]

An organism phagocytose another organism then their DNA is mixed to gether. I guess the enzymes that read and transfer and do work on the new DNA just showed up somehow. Nice story, but its just a story. Not reality in any form.

[@KoalaMeatPie]

Praise plate tectonics for saving us from Snowball Earth!