CORRECTION: Dimetrodons (pelycosaurs) were 'reptile shaped' (reptilomorphs) but did NOT evolve from reptiles. Two major groups evolved from the earliest amniotes: sauropsids (which evolved into reptiles & birds) and synapsids (which evolved into mammals). Because pelycosaurs were synapsids, they actually never evolved 'from' reptiles, they just shared a close ancestor with them (the earliest amniotes). These earliest amniotes were called reptilomorpha (reptile-shaped animals). The classification of 'reptiles' underwent some modification a couple decades ago and apparently my textbook had not adopted that change even though it was written relatively recently, so I apologize for any confusion! Please thank my loyal follower, Ted Etienne, for catching this mistake! ;D
@@tedetienne7639 Thank me? No thank YOU Ted! These are kind of things that makes me so happy to have such a knowledgeable audience. I am only human so I am bound to make mistakes, but when you catch them and help me out, that is really awesome! ;D
@@GEOGIRL Thanks for the clarification up date. This is all good stuff .Consensus agreement can change very quickly but some of us will unfortunately continue with what we know already. Also today's mistakes sometimes provoke tomorrow's new knowledge.
Hey I just found your channel and I love it!! I've always been interested in earth's past. I have so many books on prehistory and books on dinosaurs as well as many hours reading the wiki. Glad to see someone teaching others and getting them interested in the beauty of our past.
I think it's super cool to see life stumble on itself when it's first natural response to predation was bulk up, and when it realized that wasn't working it took the better, faster route. Now that's evolution!
Ginkos are freaking cool! First they turn this nice yellow, a rather mellow color, Then they drop almost ALL of their leaves in one night. Ginkos and monkey puzzle trees and redwoods are 3 of the most awesome trees...
Hi Geo Girl, I notice that "Earth System History" was written by Steven M. Stanley. When I was an Honors Historical Geology Student in the '80s, we used Stanley's "Earth and Life Through Time" as one of our texts. I still have it in my library of references. Sincerely: George F. Spicka, Curator of Paleontology (Collections Manager), Natural History Society of Maryland
Like others I also just discovered your site. I took Geology 101 in 1966 and fell in love with it because it taught me why, how and where I came from. I told my professor that I wanted to change my major and he asked me what were my goals in a career because in the mid 60s geologist were either teaching or driving cabs. So he dissuaded the change. Then in 1973 we had the Arab oil embargo, North Sea and Gulf of Mexico oil discoveries and geologist were in big demand. Please keep up your postings and I will check out the ones I missed. Very well presented. Thanks.
Came back again for this presentation. I suppose being an artist I possess an imagination which takes me anywhere Geo Girl presents, in any earth time. following learning and seeing recreated images of flora and fauna millions of years ago, the conjured shapes of scenes almost too beautiful to behold in each epoch slowed down to our speed. Where would I go first? I think 100 million years ago during the ebb and flow of the Western Seaway in North America. Over 600 miles wide and 2000 miles top to bottom. My fascination would be the offshore islands west of Laramidia and the diversity of fauna inhabiting them. Still have to watch out for Spinosaurus.
i know there are rules in nature but its amazing how broad the combinations are that are possibel. we talk a lot about the animals evolving, but for me it seems that plants are also even interresting, the looks of the plantlife in the past was so different, alien, i wish i coud see it, but im happy with the next thing, you people that give me the chance to make an image for me of how our planet, life, evolved. so thank you geo girl for taking us along in the past, maybe it will give us a change to understand who we are today.... respect for your work geo girl! greetings from a belgian waffle:D
Oooh you're from Belgium, that's so cool! Thanks for watching and thanks for the comment! I totally agree, a lot of the plants looked super alien back then compared to now. I so badly wish we had time machines to go feel and touch them! haha
Love the Carboniferous! Spent quite a bit of my Alaska career studying it, both in the subsurface and the field. So many stunning exposures in the Brooks Range. I remember several Mississippian limestone bedding surfaces that that were so fossiliferous and in situ that you felt like a time traveler walking a Missssippian shallow shelf. Another comment that jogged my old memory banks was your mention of the ginkgo tree, Ginko biloba. When I was cramming for paleontology finals at UC Berkeley I frequently would sit on a bench, just outside the department of paleontology’s building, that was shaded by the most magnificent ginko tree I’ve ever scene. It was my special place. I saved a leaf from that tree that I incorporated into a bookmark…I have it to this day. Wonderful video Rachel!
Ginko trees are wonderful and more people should plant them. They have a very nice upright growth pattern that requires very little pruning. Also, the wood is very flexible. I have a large ginko tree here in Lincoln, Nebraska. Years ago, we had a serious ice storm in October, while most trees still had leaves. The destruction was extensive with branches down all over. Most trees had heavy damage and many trees completely collapsed. The ginko's branches were weighted down with so much ice, they touched the ground all around it. But when the ice melted, the branches came back up. I didn't have to prune it at all while the other trees had me taking a dozen pick-up loads of branches to a drop-off site where the National Guard was at work. So, everybody plant ginko biloba!!
Don, I was always jealous of the exploration teams who got to go mapping and sampling in the Brooks Range while I only got to look at core on the slope (which was fun/interesting but not exciting). Imagine how it must have felt to know that you are one of only a few humans to see certain views and step on certain ridges or see herds of rarely seen animals and birds in their habitat.....special memories I bet. I bet you have some bear stories too.
Wow Alaska has rocks that old? Based on the Baja BC series Nick Zentner has done it seems there is good geological evidence such as the ophiolite "Z" and paleomagnetic and seismic tomography that Alaska was part of a vast old arc complex which had been out in the Ocean prior to North America ramming into it in the Jurassic after the break up of Pangaea. If that arc complex/microcontinent has stuff that old I wonder just what sorts of fascinating things lived and evolved there? There seems to have been a lot of really old arc complexes which date to the late Neoproterozoic in terms of ages. It seems the "so called "ribbon continent" microcontinent of accretionary arc complexes and fragmentary terrains must have been one of those ancient arcs which had managed to survive getting crushed up into the formation of Pangaea up until it started colliding with North America during the Mesozoic/early Paleogene.
So one important detail of the coal belt is that they generally didn't form on continents instead the coal deposits were found along what was then numerous mature topical volcanic arcs mush like modern Indonesia which would over the course of the Carboniferous become accreted/smashed between the continents Laurentia Baltica Siberia and Gondwana. This detail is important context because the late Devonian to late Permian was the great late Paleozoic ice age which involved numerous glaciation episodes interspersed with interglacials following the Milankovitch cycles for over a hundred million years. This caused significant changes in sea levels which caused environmental shifts between shallow tropical seas and tropical jungles. These sea level fluxes as well as the formation of deep basins during arc accretion where submerged organic material can accumulate was likely the true reason behind the great carboniferous coal belts with the mountain building metamorphism finishing the details behind the large frequency coal formation during this time. Also regarding the giant millipedes Arthropleura the discovery of giant Arthropleura living during times with much lower oxygen levels throws out the hypothesis that their large size was the cause of their gigantism instead it seems likely that the absence of competition was what likely enabled them to grow to large sizes then. The timeline for early land life whether myriapods chelicerates or insects is last I checked largely unresolved since the first appearance of these groups in the fossil record were already highly advanced and diverse which presumably couldn't have come from nowhere. Insects were likely around far earlier since the oldest fossils from around 400 Ma had already developed wings likewise by the time Myriapods appear into the fossil record in the Silurian the modern groups had already radiated and diversified. The same is true with Chelicerates with them having appeared in the fossil record largely already diversified. In fact the marine examples the Eurypterids and Horseshoe crabs had an odd peculiarity that they had to return to land to reproduce likely as in the modern counterparts of Horseshoe crabs(Xiphosura) their young lacked the ability to breathe in water until after their first major molt. We have reason to believe this applied to them since the vast majority of their fossil record are exoskeleton molts which in modern examples are produced whenever the animals come to shore to spawn. This along with phylogenetic evidence which identifies Horseshoe crabs as unequivocally being the sister group to the unfortunately poorly studied arachnid group called hooded tick spiders Ricinulei nested deep within the arachnid family tree. Notably supporting this is the mystery of why all arachnids as well as the Xiphosura and Eurypterids which have conventionally been thought to be sister groups to arachnids all possess strong UV fluorescence particularly tuned to the higher energy UV B and UVC radiation blocked out by the modern ozone layer. Moreover all these organisms appear to represent a single radiation to larger body sizes within a otherwise paraphyletic grouping of mites thus suggesting our classical picture of terrestrial colonization is likely incorrect. Thus there is growing evidence to suggest that the lack of these creatures in marine fossil record and their sudden appearance of already highly diverse and "advanced" terrestrial forms in the early Paleozoic is likely a result of fossilization bias of marine environments over terrestrial ones. I.e. animals had already come ashore much earlier based on molecular clock estimates and the lack of fossils some of them namely chelicerates and Myriapods had likely come ashore or into near shore/freshwater environments by the Cambrian likely following the colonization of land by the green algae from which plants descend. So not really new to land just new to gigantism though given they were all from the complex subduction fed volcanic archipelagos could this have been island gigantism?
I would like to compliment the host. Everything is very well done. She happened to read good sources. However, she has a fantastic way to deliver the "matter". She has a future in the science divulgation field. I apologize to all who has been following this channel, but I just came across her. Good job girl!
I have a Ginko biloba near my house. It's an astonishingly beautiful tree. I can imagine what a forest of ginkos would have looked like in a carboniferous autumn.
The synapsids like pelycosaurs and the later therapsids are no longer referred to as reptiles-- only the sauropsids nowadays. Older literature, though, will refer to them as "mammal-like reptiles," but that's no longer in use. Great video!
Hey GEO GIRL, I am a geologist from Tübingen, Germany. This is a great presentation. Really enjoyed it. You ha a little slip of tongue at 11:10 so now I can´t stop picturing carnivorous swamps. Thanks a lot!
Haha I think I did say carboniferous swamps but I mumbled so badly that it did sound a lot like carnivorous lol! That is so funny, I don't even want to know what that would mean 😅 That's so cool that you are a geologist in Germany, there are some really amazing research institutions in Germany that I hope to someday visit ;D
The oldest winged insect known right now is Delitzschala bitterfeldensis. (It's probably German paleontologists trying to troll other people not being able to pronounce the name.)
I'm going to be honest with you, I've never actually wondered what wacky creatures were running around before the dinosaurs but the algorithm has decided it's about damn time I learned
I read a hypothesis recently that speculated that the Carboniferous may not have been swampy. The reason we find such massive coal deposits from that period may be that pulp eating fungi had not yet appeared. Hence, the accumulation of forest debris that we now find as coal. I thought that was interesting, if it turns out to be correct. Fascinating presentation. Thanks!
Yes, fungi and other destruents have not developed yet on land, nothing could dissolve the lingin. It must have been surreal to behold these trunks to pile up and what would it have sounded like? All the pressure. Oil btw came late in the flat seas of the cretacious. Oil is the accumulated fluids of marine life, one could say coal and oil is concentrated former life.
@@nyoodmono4681 Oh interesting, I wonder if you mean all fungi? or just specific pulp eating fungi hadn't evolved on land yet? Because I read that fungi spread to land long before this, but I know it's still debated so I am curious what you've seen? :D
@@GEOGIRL Tbh i have only heard this from different sources without studying it. It would probably be more accurate to say that fungi and insects needed to evolve and learn how to digest this new lingen rescource on land. But it was definetly a crazy time where things on land changed so fast and even changed the atmosphere, seemingly.
Being warm-blooded would be especially useful for nocturnal animals, because they can be very energetic when their cold-blooded competitors are sluggish because of cool nights.
I love that you talked about corals! I feel like no one gives enough emphasis to the reef creatures! Super curious about coral evolution they’ve been surviving for what 500 million years? So cool! You’re awesome!
Thank you! I agree no one cares about invertebrates enough! It is so sad, but don't worry, I will always include invertebrate discussion in my videos ;)
When I was a kid, we used to collect crinoids walking along the shore of Lake Michigan. They were just stem parts, just like stone cheerios. Fun to make necklaces with.
This summer I was working in a selective cut white pine forest. There were huge white pines scattered around while all other trees had been cut. It reminded me of the drawings I’d seen of lycopod forests.
PS. Fascinating video. Makes me want to reread Benton’s, and Brannen’s, books. When I retire, I hope to return to school and get a bachelors in one of the paleo fields. I’d do it now except by the time I graduate I’d be retirement age anyway, so may as well wait.
I really did enjoy this video - expanded my brain considerably! Two questions (though maybe you have answered them in other videos): (1) do you think that the high oxygen level you mention gave rise to, or encouraged. the development of wings in insects? and (2) teeth - did some amphibians have teeth, or did teeth evolve again in reptiles?
Ooo great questions! To be honest I don't know haha, BUT my guess for (1) is no, because I feel that the oxygen wouldn't have benefitted in any way with the development of wings (maybe their size, but not their presence), because wings is SUCH an advantageous evolutionary trait that I feel it would've evolved no matter the oxygen concentration and it just so happened to be around this time. Now for (2) I am also guessing, but I would say probably both. My guess is because the fish, like Tiktaalik, had teeth when they transitioned to land that some of the early amphibians had teeth, some probably lost them and then re-evolved them in some groups later on because (like wings) teeth are super evolutionarily advantageous so they probably evolved many times in many groups. (BUT AGAIN, these are my educated guesses, I am not an evolutionary expert) ;)
Just found your chanel and I can see myself binge watching the whole thing in the coming weeks. Quality content. Note for history: subbed at 12.8k subscribers. I hope your channel blows up in popularity in the coming year!
I have a piece of shale that I found in the eastern rocky mountains west of Calgary Alberta [25 years ago]. It is packed with Crynoid stems and lacy Bryzoans. I have always wondered how old it was, now I know...Early Carboniferous [Mississippian]. Thanks very much Geo Girl!
Note: not a professional, but I think I recall someone who knows better than me saying cor-day-tees for cordaites. And yes, the plant folks and the critter folks should have gotten together on those.
Thank you! Someone else told me that in the comments the other day too, so I think you are absolutely correct! :D And yes, they really should talk more haha
Thank you! What an informative video! The late Paleozoic has always been a weak spot in my historical geology knowledge. I’m really glad to be filling those gaps! Also, Cordaites vs. Chordates vs. Cordates (heart-shaped leaves), and Archaeopteryx vs. Archaeopteris (my favorite Paleozoic plant!). I don’t know who came up with these names, but they really could have made more of an effort to be less confusing!
@@GEOGIRL We do know that there was more oxygen in the earth's atmosphere during the Carboniferous period. However, the only way to know exactly how much more oxygen was in the Earth's atmosphere at the time, We would have to travel back to the Carboniferous period and do atmospherical experiments.
I found some of those Crinoid stems in a rock wall outside a motel parking lot in El Paso Tx about 20 years ago. I was having a smoke outside the motel room and noticed the Crinoid stems embedded in the rock in the wall. I had thought they were prehistoric worm segments at the time. They were around the thickness of a woman's pinky finger.
I find Tiktaalik and acanthastegans fascinating. I'm sure they must have found life difficult and challenging having to accustom themselves to having to bear their entire weight on their limbs.
Just an FYI, latest research suggests arthropods large size might not be as tied to oxygen as thought, many large milliped fossils have been found prior to the rise in oxygen
Great summary but the terms used on the mammalian / reptilian lineages runs slightly contrast to current conventions which seems to perturb palaeontologists today. As I understand it: The ancestors to both reptiles (diapsid) and mammals and their relatives (synapsids) were the ‘Amniotes’ and it was these anapsid descendants of amphibians that laid these watertight eggs. It was at this point the synapsids and diapsids split, which is why the term ‘mammal-like reptile’ has fallen out of use in the last decade; the stem-mammals evolved from amniotes, as did reptiles rather than mammals coming from reptiles. Dimetrodon was an offshoot of this lineage (Sphenacodontidae) rather than a direct ancestor of ours, and it’s currently believed it’s sail would be fairly useless for thermo-regulation as it’s vascular infrastructure seems unlikely to have delivered the flow needed to do so, and no other ectothermic life forms have converged on the same solution, making sexual selection another possibility, but there’s no evidence yet of sexual dimorphism which would be expected, but science is always finding new things, so we just don’t know at the moment… The evolution of these synapsids is amazing and well worth looking into further if you get a chance, every bit as amazing as the more popular dinosaurs
I liked what you said about rugose and tabulate coral. It was sobering. Mass extinction events are one of those natural tragedies of history. I live in Australia and it just breaks my heart when the Great Barrier Reef is being destroyed, but the bleaching events are caused by people.
Fascinating worlds. The developing terrestial flora seem to have led to a drastic decline in CO2, yet the temperatures did ot change untill the Karoo Ice age.
Good video. I like all the plants and animals. Were the Carboniferous trees built more like banana trees, with more of a stem than a woody trunk? Also, what happened to dimetrodon when it got really windy? I would've liked to see one of those big hellbenders (giant river salamander). I wonder if they were poisonous, and how their skin toxins evolved? So much to discover.
Yes, exactly, more of a stem than a woddy trunk, at least for the early swamp trees, before large coniferous forests which were more woody. Also, I love the wind question LOL, I assume he either just went in the water, or hid behind some the trees haha. And what an interesting point about the skin toxins! Now you've got me wondering about their evolution too! I wish skin toxin residue was preserved in the rock record... I wonder if maybe some part of it is.. That'd be such a cool thing to study!
Hi, I read that the reason the carboniferous produced coal deposits around the world is that the trees began producing lignin to strengthen their trunks - but the decay organisms were unable to break down lignin until millions of years later.
Great video - thank you for clearing up some details of the plants during the carboniferous period. I thought that one of the huge factors that stopped the dinosaurs rebounding was the evolution of grasses.
Hi Geo Girl, Your description of the Carboniferous forest environment filled with living lycopods as well as dead trunks and fallen lycopods got me thinking about an Alie Ward Ologies podcast where a guest was described these forests in a similar manner. They went on to say that there is a theory that decomposers hadn't evolved yet, or perhaps not to todays extent, so that the waterways of the swamps were a massive tangle of living plants, trunks and 'logs'. I've never heard this discussed, but in that type of environment it would seem that having leg like body structures to allow an fish to pull itself between and at times over all the live and dead vegetation would give it a huge advantage. Maybe it was this environment that drove the first vertebrates onto land. What do you think?
@@barbaradurfee645 Alie Ward is wonderful, can't go on a road trip without loading in a bunch of her podcasts. We listened to the Crow one as well, fascinating and a little disturbing-LOL. I'm very much enjoying the Geo Girl You Tube channel as well, she does an equally great job here.
I went to drumheller in Alberta, Canada this summer. There is a huge museum there about dinosaurs, since there are tons and tons of dinosaurs fossils around from the cretaceous. the musuem has a very diverse collection, and they also go over the history of earth (although the precambrien sections is barely represented). Iin the permian section they represented dimetrodon-like and therapsids as reptile-like mammals or something like that. You're not alone doing this error if that makes you feel better xD . Reptile definition is not very clear but it does not include synapsids :) BTW did you know they just found there a couple week ago a complete haplosaur with it's skin still intact ? That's insane :O
13:20 f: I "recently" saw a documentary where they claimed the carboniferous sky was not so much blue but had a sepia tone due to the high oxygen content. If so, why?
Thanks so much for this comment. It is a very simple comment, but you have no idea how much it motivates me to read this sentence, especially now that I am growing faster and getting some not so nice opinions shared on my channel! lol Thank you for your support and encouragement
Thanks so much! I don't have that much of it, it's more just me regurgitating what's in my textbooks, but I would eventually love to have all this knowledge in my brain :D
Isn't this the period of time when the oxygen in Earth's atmosphere was over 30% and that allowed for HUGE invertebrates like giant insects? Also, what life forms in this period of time were humans' ancestors and what other modern day animals are they the ancestors of? Presumably all mammals at least.
Yep! Like I mentioned in the video, the insects were able to get huge due to the increased oxygen and the amphibians that had just evolved from lobed finned fished that began to walk on land evolved into reptiles which diversified into many groups, including the therapsids that later evolved into mammals ;)
Yes! Well, keep in mind, it is their test (or hard outer shell) that reaches that size, their cell is the tiny thing at the very center that drove the process of building that shell, but the cell itself does not reach a size that large. Foraminifera tests (or shells) have been shown to reach up to 20 cm!!! Isn't that crazy :D So cool!
@@GEOGIRL Okay, so it's not the cell itself. But that's still superweird. I've been learning a lot of really amazing things about microorganisms latetly. Bacteriophage virusses are scary! Not just what they do but the way they are built. They look like some insidious micro-weapon out of a science ficton spy movie.
@@NelsonDiscovery Yes, the micro-world is quite crazy both the things they do and their physical appearances! I feel like microbes have certainly been the inspiration behind some movie ideas haha
Really interesting stuff. Some of my favorite critters come from old times, like Dunkleosteus and Megatherium, I remember seeing them in books when I was younger. Nice to learn more about them in more modern times, thank you.
Aragonite formation is favored over calcite formation under conditions where the Mg/Ca ratio is high because the aragonite mineral structure can incorporate more Mg than than the calcite mineral structure can. The reason the ions can only 'fit' in certain mineral structures (atomic arrangments) is due to the difference in ion radius (size) of the Ca ion vs the Mg ion. Hope that makes sense ;)
OMG That's a great question, I never even thougth about this! From my experience, larger brain doesn't always mean smarter or more complex in the animal kingdom haha, but I don't know for sure how the millipedes brains were affected. I think that is difficult to reconstruct since their brains weren't preserved, but I am sure you are right that something must've changed.
geogirl it’s been awhile! Sorry I haven’t been active I’ve been super busy with college. What’s a good way to contact you? I have something fun brewing in my mind and need advice!
A very nice and simultaneously complete and succinct presentation! I have always wondered, though, how is it that carboniferous forests weren't regularly obliterated by terrifyingly huge and unstoppable forest fires, given the 35% oxygen levels!
Well remember, plants had just started to spread over land so Chris is right that they were relatively far apart (both the bunches and the individual trees), and also these were all swamp lands so very moist! There were only beginning to be forests in dry regions at the time and I bet they did experience forest fires often, but the swamps were too moist. Another thing to remember is much of the land was still just rock, grasses and grasslands didn't evolve until millions of years later in the Cenozoic. :)
@@MrChristianDT In my own defense, I didn't know until I watched this video that carboniferous forests were sparse, though I did begin to consider the possibility (I'm not trying to backdate my knowledge, really. Maybe. NO REALLY!) that perhaps sparse forest structure was part of survival strategy while I was composing this comment (or shortly thereafter).
@@GEOGIRL I know little about forest fire dynamics, especially at high oxygen concentrations (and I don't intend to find out by direct experience), but I'm pretty sure that even very green wood will happily combust at 35% oxygen levels (I know, I know it's not 'wood' at this time, but still...), furthermore, at least the tops (presumably where all the juicy volatiles are concentrated) of the trees would be vulnerable. Also, would great conflagrations (likely lasting just a few hours or maybe days) really show up in the fossil record? My intuition says it would, at least sometimes, but I know next to nothing about taphonomy. As regards underbrush/grasses, I understand that these didn't really exist at the time, but.. 35 PERCENT!!! C'mon! Also, I feel constrained to point out that even you said maybe these weren't actually swamps. Anyway, as I said, I really enjoy your content but I'm quite sure that comment sycophancy isn't the path to better content. Cheers!
@@johnwiles4391 Oh my gosh, I wasn't at all trying to be sycophantic, I am sorry it came across that way, I only wanted to try to answer the question ;) Like I said, I think you are right that there must have been forest fires then, and I am sure they are preserved in the rock record. I just wanted to point out how moist things were because most of these newly moved to land trees and vegetated environments were incredibly moist and swampy, and I thought that fires only started in dry regions (BUT I could always be wrong I am only human, I am just given what I think is a good reason to why there might not have been more fires than today) :)
Invited this it’s really cool how our ancestry began with worm like creatures with a notochord that gave rise primitive fish which gave rise to jawed fish which gave rise to lobe finned fishes which gave rise to amphibians which gave rise to amniotes which gave rise to stem mammals which gave rise to mammals which eventually gave rise to us via the ancestor shared by rodents, Lagomorphs and primates
An excellent work although might not be of all the public interest. Details well cared, the presentation, including narration, is marvelous, visually appealing as well. Terrestrial animals both vertebrates & invertebrates may often be featured for that period, the video introduces events under water, during transition & the landscape which sets up a stage for newcomers. The structure of the footage is well considered, which makes it distinct from others. Personally, terrestrial creatures in mesozoic is of principal interest. Looking forward to it. Incidentally "before mammals" ? Could be misleading. Yes, those stem groups of mammalian lineage made a debut, but the term sounds misnomer (hair-splitting though). Thanks for your dedication!
I think it would be really great if I could travel back to the Carboniferous period and take photos, plant samples, spore cases, and seeds back with Me.🙂
Great video! My PhD advisor says we can't quantify living biomass on preservation bias! Sure we see METRIC LOADS of coal, but this is actually due to the lack of decomposers at this time! Cellulose is still impossible to breakdown in your gut it's tough stuff, reserved for only a few niche organisms bold enough to evolve to break it down :D cheers!
I believe Cordaites is pronounced "Core-dye-tees" from what I found online. Great and very informative video nevertheless! This is definitely one of my favorite time periods.
Yep, there are 5 mass extinction events in the Phanerozoic Eon that have been recongnized as being the 5 largest extinctions of this eon. However, in recent decades, they have re-visited other mass extincitons in Earth's history any may end up adding more to that list :) The 5 right now are the End-Ordovician, the End-Devonian, the End-Permian, the End-Triassic, and the End-Cretaceous Mass Extincitons ;)
CORRECTION: Dimetrodons (pelycosaurs) were 'reptile shaped' (reptilomorphs) but did NOT evolve from reptiles.
Two major groups evolved from the earliest amniotes: sauropsids (which evolved into reptiles & birds) and synapsids (which evolved into mammals). Because pelycosaurs were synapsids, they actually never evolved 'from' reptiles, they just shared a close ancestor with them (the earliest amniotes).
These earliest amniotes were called reptilomorpha (reptile-shaped animals). The classification of 'reptiles' underwent some modification a couple decades ago and apparently my textbook had not adopted that change even though it was written relatively recently, so I apologize for any confusion!
Please thank my loyal follower, Ted Etienne, for catching this mistake! ;D
Thank you so much! And you even gave me a shout-out! >>blushes in embarrassment
@@tedetienne7639 Thank me? No thank YOU Ted! These are kind of things that makes me so happy to have such a knowledgeable audience. I am only human so I am bound to make mistakes, but when you catch them and help me out, that is really awesome! ;D
@@GEOGIRL Thanks for the clarification up date. This is all good stuff .Consensus agreement can change very quickly but some of us will unfortunately continue with what we know already. Also today's mistakes sometimes provoke tomorrow's new knowledge.
@@DavoidJohnson "Today's mistakes sometimes provoke tomorrow's new knowledge" Wow, I love that ;D
I was going to point that out. Thanks for the correction.
Hey I just found your channel and I love it!! I've always been interested in earth's past. I have so many books on prehistory and books on dinosaurs as well as many hours reading the wiki. Glad to see someone teaching others and getting them interested in the beauty of our past.
Thanks so much! So glad you like the topic and my channel :D
I think it's super cool to see life stumble on itself when it's first natural response to predation was bulk up, and when it realized that wasn't working it took the better, faster route. Now that's evolution!
Ginkos are freaking cool! First they turn this nice yellow, a rather mellow color, Then they drop almost ALL of their leaves in one night. Ginkos and monkey puzzle trees and redwoods are 3 of the most awesome trees...
Hi Geo Girl, I notice that "Earth System History" was written by Steven M. Stanley. When I was an Honors Historical Geology Student in the '80s, we used Stanley's "Earth and Life Through Time" as one of our texts. I still have it in my library of references. Sincerely: George F. Spicka, Curator of Paleontology (Collections Manager), Natural History Society of Maryland
Oh wow that's so cool! Thanks for the comment, nice to have a Curator of Paleontology here ;D
Like others I also just discovered your site. I took Geology 101 in 1966 and fell in love with it because it taught me why, how and where I came from. I told my professor that I wanted to change my major and he asked me what were my goals in a career because in the mid 60s geologist were either teaching or driving cabs. So he dissuaded the change. Then in 1973 we had the Arab oil embargo, North Sea and Gulf of Mexico oil discoveries and geologist were in big demand. Please keep up your postings and I will check out the ones I missed. Very well presented. Thanks.
Thank you so much! I am so glad you enjoy and appreciate my posts ;D
Came back again for this presentation. I suppose being an artist I possess an imagination which takes me anywhere Geo Girl presents, in any earth time. following learning and seeing recreated images of flora and fauna millions of years ago, the conjured shapes of scenes almost too beautiful to behold in each epoch slowed down to our speed.
Where would I go first? I think 100 million years ago during the ebb and flow of the Western Seaway in North America. Over 600 miles wide and 2000 miles top to bottom. My fascination would be the offshore islands west of Laramidia and the diversity of fauna inhabiting them.
Still have to watch out for Spinosaurus.
i know there are rules in nature but its amazing how broad the combinations are that are possibel. we talk a lot about the animals evolving, but for me it seems that plants are also even interresting, the looks of the plantlife in the past was so different, alien, i wish i coud see it, but im happy with the next thing, you people that give me the chance to make an image for me of how our planet, life, evolved. so thank you geo girl for taking us along in the past, maybe it will give us a change to understand who we are today.... respect for your work geo girl! greetings from a belgian waffle:D
Oooh you're from Belgium, that's so cool! Thanks for watching and thanks for the comment! I totally agree, a lot of the plants looked super alien back then compared to now. I so badly wish we had time machines to go feel and touch them! haha
Just think our plant and animal life of today will be unrecognizable and alien to those of the future
@@SoulDelSol Wow, you're right, that is so trippy to think about! haha
Love the Carboniferous! Spent quite a bit of my Alaska career studying it, both in the subsurface and the field. So many stunning exposures in the Brooks Range. I remember several Mississippian limestone bedding surfaces that that were so fossiliferous and in situ that you felt like a time traveler walking a Missssippian shallow shelf. Another comment that jogged my old memory banks was your mention of the ginkgo tree, Ginko biloba. When I was cramming for paleontology finals at UC Berkeley I frequently would sit on a bench, just outside the department of paleontology’s building, that was shaded by the most magnificent ginko tree I’ve ever scene. It was my special place. I saved a leaf from that tree that I incorporated into a bookmark…I have it to this day. Wonderful video Rachel!
Wow that's so cool! Mississipian limestone is always so packed with cool fossils, I love it! :D
Carboniferous Alaska??
Wow hard to imagine☺️
Ginko trees are wonderful and more people should plant them. They have a very nice upright growth pattern that requires very little pruning. Also, the wood is very flexible. I have a large ginko tree here in Lincoln, Nebraska. Years ago, we had a serious ice storm in October, while most trees still had leaves. The destruction was extensive with branches down all over. Most trees had heavy damage and many trees completely collapsed. The ginko's branches were weighted down with so much ice, they touched the ground all around it. But when the ice melted, the branches came back up. I didn't have to prune it at all while the other trees had me taking a dozen pick-up loads of branches to a drop-off site where the National Guard was at work. So, everybody plant ginko biloba!!
Don, I was always jealous of the exploration teams who got to go mapping and sampling in the Brooks Range while I only got to look at core on the slope (which was fun/interesting but not exciting). Imagine how it must have felt to know that you are one of only a few humans to see certain views and step on certain ridges or see herds of rarely seen animals and birds in their habitat.....special memories I bet. I bet you have some bear stories too.
Wow Alaska has rocks that old? Based on the Baja BC series Nick Zentner has done it seems there is good geological evidence such as the ophiolite "Z" and paleomagnetic and seismic tomography that Alaska was part of a vast old arc complex which had been out in the Ocean prior to North America ramming into it in the Jurassic after the break up of Pangaea. If that arc complex/microcontinent has stuff that old I wonder just what sorts of fascinating things lived and evolved there? There seems to have been a lot of really old arc complexes which date to the late Neoproterozoic in terms of ages. It seems the "so called "ribbon continent" microcontinent of accretionary arc complexes and fragmentary terrains must have been one of those ancient arcs which had managed to survive getting crushed up into the formation of Pangaea up until it started colliding with North America during the Mesozoic/early Paleogene.
So one important detail of the coal belt is that they generally didn't form on continents instead the coal deposits were found along what was then numerous mature topical volcanic arcs mush like modern Indonesia which would over the course of the Carboniferous become accreted/smashed between the continents Laurentia Baltica Siberia and Gondwana. This detail is important context because the late Devonian to late Permian was the great late Paleozoic ice age which involved numerous glaciation episodes interspersed with interglacials following the Milankovitch cycles for over a hundred million years. This caused significant changes in sea levels which caused environmental shifts between shallow tropical seas and tropical jungles. These sea level fluxes as well as the formation of deep basins during arc accretion where submerged organic material can accumulate was likely the true reason behind the great carboniferous coal belts with the mountain building metamorphism finishing the details behind the large frequency coal formation during this time.
Also regarding the giant millipedes Arthropleura the discovery of giant Arthropleura living during times with much lower oxygen levels throws out the hypothesis that their large size was the cause of their gigantism instead it seems likely that the absence of competition was what likely enabled them to grow to large sizes then.
The timeline for early land life whether myriapods chelicerates or insects is last I checked largely unresolved since the first appearance of these groups in the fossil record were already highly advanced and diverse which presumably couldn't have come from nowhere. Insects were likely around far earlier since the oldest fossils from around 400 Ma had already developed wings likewise by the time Myriapods appear into the fossil record in the Silurian the modern groups had already radiated and diversified. The same is true with Chelicerates with them having appeared in the fossil record largely already diversified. In fact the marine examples the Eurypterids and Horseshoe crabs had an odd peculiarity that they had to return to land to reproduce likely as in the modern counterparts of Horseshoe crabs(Xiphosura) their young lacked the ability to breathe in water until after their first major molt. We have reason to believe this applied to them since the vast majority of their fossil record are exoskeleton molts which in modern examples are produced whenever the animals come to shore to spawn. This along with phylogenetic evidence which identifies Horseshoe crabs as unequivocally being the sister group to the unfortunately poorly studied arachnid group called hooded tick spiders Ricinulei nested deep within the arachnid family tree. Notably supporting this is the mystery of why all arachnids as well as the Xiphosura and Eurypterids which have conventionally been thought to be sister groups to arachnids all possess strong UV
fluorescence particularly tuned to the higher energy UV B and UVC radiation blocked out by the modern ozone layer. Moreover all these organisms appear to represent a single radiation to larger body sizes within a otherwise
paraphyletic grouping of mites thus suggesting our classical picture of terrestrial colonization is likely incorrect.
Thus there is growing evidence to suggest that the lack of these creatures in marine fossil record and their sudden appearance of already highly diverse and "advanced" terrestrial forms in the early Paleozoic is likely a result of fossilization bias of marine environments over terrestrial ones. I.e. animals had already come ashore much earlier based on molecular clock estimates and the lack of fossils some of them namely chelicerates and Myriapods had likely come ashore or into near shore/freshwater environments by the Cambrian likely following the colonization of land by the green algae from which plants descend.
So not really new to land just new to gigantism though given they were all from the complex subduction fed volcanic archipelagos could this have been island gigantism?
Love your thoughtful contribution
I would like to compliment the host. Everything is very well done. She happened to read good sources. However, she has a fantastic way to deliver the "matter". She has a future in the science divulgation field. I apologize to all who has been following this channel, but I just came across her. Good job girl!
Thank you so much, this is so kind! :)
I have a Ginko biloba near my house. It's an astonishingly beautiful tree. I can imagine what a forest of ginkos would have looked like in a carboniferous autumn.
The synapsids like pelycosaurs and the later therapsids are no longer referred to as reptiles-- only the sauropsids nowadays. Older literature, though, will refer to them as "mammal-like reptiles," but that's no longer in use. Great video!
Hey GEO GIRL, I am a geologist from Tübingen, Germany. This is a great presentation. Really enjoyed it. You ha a little slip of tongue at 11:10 so now I can´t stop picturing carnivorous swamps. Thanks a lot!
Haha I think I did say carboniferous swamps but I mumbled so badly that it did sound a lot like carnivorous lol! That is so funny, I don't even want to know what that would mean 😅
That's so cool that you are a geologist in Germany, there are some really amazing research institutions in Germany that I hope to someday visit ;D
What i heard (but i "hear" a lot of things) was halfway between: Carniferous. Soooo... meat-bearing swamps? 🙃
Omg so many views! I’m so happy you’re starting to get the recognition you deserve! 😊
Aw thank you! So grateful for your support! ;D
The oldest winged insect known right now is Delitzschala bitterfeldensis. (It's probably German paleontologists trying to troll other people not being able to pronounce the name.)
I'm going to be honest with you, I've never actually wondered what wacky creatures were running around before the dinosaurs but the algorithm has decided it's about damn time I learned
The ALGORITHM rules 😉
Let's face it, dinos get all the glory except for Dimetrodons, and a lot of people think they are dinos too.
The amniotic egg and thicker skin were one of those breakthroughs in evolution.
100%!
I listen to this to bed, 4 nights in a row now!
You explain it so well with such a soothing voice. Thank you!
Oh my gosh! 4 nights in a row, wow, you are great thanks! haha ;) So glad you enjoy it so much!
@@GEOGIRL One of my fav topics yes! , a strange time that actually existed! 😮😮😮
i learn so much from your channel!! its amazing 😁👍
Thank you! I am so glad you find it informative :D
I read a hypothesis recently that speculated that the Carboniferous may not have been swampy. The reason we find such massive coal deposits from that period may be that pulp eating fungi had not yet appeared. Hence, the accumulation of forest debris that we now find as coal. I thought that was interesting, if it turns out to be correct. Fascinating presentation. Thanks!
Oh wow! That's such an interesting hypothesis! I am going to have to read about that, thanks for sharing ;D
Yes, fungi and other destruents have not developed yet on land, nothing could dissolve the lingin. It must have been surreal to behold these trunks to pile up and what would it have sounded like? All the pressure. Oil btw came late in the flat seas of the cretacious. Oil is the accumulated fluids of marine life, one could say coal and oil is concentrated former life.
@@nyoodmono4681 Oh interesting, I wonder if you mean all fungi? or just specific pulp eating fungi hadn't evolved on land yet? Because I read that fungi spread to land long before this, but I know it's still debated so I am curious what you've seen? :D
@@GEOGIRL Tbh i have only heard this from different sources without studying it. It would probably be more accurate to say that fungi and insects needed to evolve and learn how to digest this new lingen rescource on land. But it was definetly a crazy time where things on land changed so fast and even changed the atmosphere, seemingly.
This is what my bio professor told me, nothing had evolved yet to eat lignin and/or cellulose.
Being warm-blooded would be especially useful for nocturnal animals, because they can be very energetic when their cold-blooded competitors are sluggish because of cool nights.
I love that you talked about corals! I feel like no one gives enough emphasis to the reef creatures! Super curious about coral evolution they’ve been surviving for what 500 million years? So cool! You’re awesome!
Thank you! I agree no one cares about invertebrates enough! It is so sad, but don't worry, I will always include invertebrate discussion in my videos ;)
@@GEOGIRL Can you do a coral evolution theme video?
My favorite period! First stop with my time machine.
That's a great choice! I agree, this period is hard to beat! ;D
When I was a kid, we used to collect crinoids walking along the shore of Lake Michigan. They were just stem parts, just like stone cheerios. Fun to make necklaces with.
This summer I was working in a selective cut white pine forest. There were huge white pines scattered around while all other trees had been cut. It reminded me of the drawings I’d seen of lycopod forests.
PS. Fascinating video. Makes me want to reread Benton’s, and Brannen’s, books. When I retire, I hope to return to school and get a bachelors in one of the paleo fields. I’d do it now except by the time I graduate I’d be retirement age anyway, so may as well wait.
Great video! Artistic depictions of a carboniferous environment look so cool. Fun to learn about.
Thanks! So glad you liked it, I love looking for the depictions for these earth history videos ;D They are so cool!
I really did enjoy this video - expanded my brain considerably! Two questions (though maybe you have answered them in other videos): (1) do you think that the high oxygen level you mention gave rise to, or encouraged. the development of wings in insects? and (2) teeth - did some amphibians have teeth, or did teeth evolve again in reptiles?
Ooo great questions! To be honest I don't know haha, BUT my guess for (1) is no, because I feel that the oxygen wouldn't have benefitted in any way with the development of wings (maybe their size, but not their presence), because wings is SUCH an advantageous evolutionary trait that I feel it would've evolved no matter the oxygen concentration and it just so happened to be around this time. Now for (2) I am also guessing, but I would say probably both. My guess is because the fish, like Tiktaalik, had teeth when they transitioned to land that some of the early amphibians had teeth, some probably lost them and then re-evolved them in some groups later on because (like wings) teeth are super evolutionarily advantageous so they probably evolved many times in many groups. (BUT AGAIN, these are my educated guesses, I am not an evolutionary expert) ;)
@@GEOGIRL Very many thanks for replying - looking forward to more of your videos
Just found your chanel and I can see myself binge watching the whole thing in the coming weeks. Quality content.
Note for history: subbed at 12.8k subscribers.
I hope your channel blows up in popularity in the coming year!
I have a piece of shale that I found in the eastern rocky mountains west of Calgary Alberta [25 years ago]. It is packed with Crynoid stems and lacy Bryzoans. I have always wondered how old it was, now I know...Early Carboniferous [Mississippian]. Thanks very much Geo Girl!
This is so great. Love the format, and the content is so interesting! 😎👍
It's amazing that the earth could create an environment like this
Note: not a professional, but I think I recall someone who knows better than me saying cor-day-tees for cordaites. And yes, the plant folks and the critter folks should have gotten together on those.
Thank you! Someone else told me that in the comments the other day too, so I think you are absolutely correct! :D
And yes, they really should talk more haha
Thank you! What an informative video! The late Paleozoic has always been a weak spot in my historical geology knowledge. I’m really glad to be filling those gaps!
Also, Cordaites vs. Chordates vs. Cordates (heart-shaped leaves), and Archaeopteryx vs. Archaeopteris (my favorite Paleozoic plant!). I don’t know who came up with these names, but they really could have made more of an effort to be less confusing!
Hahaha! AGREED about the names! They made a lot of those too close and too confusing! LOL
@@GEOGIRL We do know that there was more oxygen in the earth's atmosphere during the Carboniferous period. However, the only way to know exactly how much more oxygen was in the Earth's atmosphere at the time, We would have to travel back to the Carboniferous period and do atmospherical experiments.
@@stephenlangsl67 well that's not going to happen!
I have a little Ginkgo Biloba in my backyard and always think of its loooong history when I looking at it 😄
*Love watching your lectures, Rachel! 🌺*
I found some of those Crinoid stems in a rock wall outside a motel parking lot in El Paso Tx about 20 years ago. I was having a smoke outside the motel room and noticed the Crinoid stems embedded in the rock in the wall. I had thought they were prehistoric worm segments at the time. They were around the thickness of a woman's pinky finger.
Excellent presentation - great video.
Thank you! ;)
I find Tiktaalik and acanthastegans fascinating. I'm sure they must have found life difficult and challenging having to accustom themselves to having to bear their entire weight on their limbs.
The Merriam-Webster dictionary says the pronunciation of "cordiates" is Kor-dites.
Just an FYI, latest research suggests arthropods large size might not be as tied to oxygen as thought, many large milliped fossils have been found prior to the rise in oxygen
Oh how interesting! I'll have to look into that, thanks for letting me know ;D
Excellent channel. Thanks for sharing your knowledge. I’m now a subscriber.
Thanks so much for the comment and for subscibing! I am so glad you like my channel :D
Great summary but the terms used on the mammalian / reptilian lineages runs slightly contrast to current conventions which seems to perturb palaeontologists today. As I understand it:
The ancestors to both reptiles (diapsid) and mammals and their relatives (synapsids) were the ‘Amniotes’ and it was these anapsid descendants of amphibians that laid these watertight eggs. It was at this point the synapsids and diapsids split, which is why the term ‘mammal-like reptile’ has fallen out of use in the last decade; the stem-mammals evolved from amniotes, as did reptiles rather than mammals coming from reptiles.
Dimetrodon was an offshoot of this lineage (Sphenacodontidae) rather than a direct ancestor of ours, and it’s currently believed it’s sail would be fairly useless for thermo-regulation as it’s vascular infrastructure seems unlikely to have delivered the flow needed to do so, and no other ectothermic life forms have converged on the same solution, making sexual selection another possibility, but there’s no evidence yet of sexual dimorphism which would be expected, but science is always finding new things, so we just don’t know at the moment…
The evolution of these synapsids is amazing and well worth looking into further if you get a chance, every bit as amazing as the more popular dinosaurs
I liked what you said about rugose and tabulate coral. It was sobering. Mass extinction events are one of those natural tragedies of history. I live in Australia and it just breaks my heart when the Great Barrier Reef is being destroyed, but the bleaching events are caused by people.
Fascinating worlds. The developing terrestial flora seem to have led to a drastic decline in CO2, yet the temperatures did ot change untill the Karoo Ice age.
Thanks for the upeodate our geology knowledge nice presentation
Of course, so glad you liked it ;D
Good video. I like all the plants and animals. Were the Carboniferous trees built more like banana trees, with more of a stem than a woody trunk? Also, what happened to dimetrodon when it got really windy? I would've liked to see one of those big hellbenders (giant river salamander). I wonder if they were poisonous, and how their skin toxins evolved? So much to discover.
Yes, exactly, more of a stem than a woddy trunk, at least for the early swamp trees, before large coniferous forests which were more woody. Also, I love the wind question LOL, I assume he either just went in the water, or hid behind some the trees haha. And what an interesting point about the skin toxins! Now you've got me wondering about their evolution too! I wish skin toxin residue was preserved in the rock record... I wonder if maybe some part of it is.. That'd be such a cool thing to study!
What a great channel!
Thank you so much! So glad you like it ;D
Hi, I read that the reason the carboniferous produced coal deposits around the world is that the trees began producing lignin to strengthen their trunks - but the decay organisms were unable to break down lignin until millions of years later.
Yea, thanks for mentioning that, that's a great point! I am actually going to be making another video about that in the future ;D
Great video - thank you for clearing up some details of the plants during the carboniferous period. I thought that one of the huge factors that stopped the dinosaurs rebounding was the evolution of grasses.
Interesting! Probably my favorite period in the paleozoic
It's a hard one to beat for sure! :D
Hi Geo Girl, Your description of the Carboniferous forest environment filled with living lycopods as well as dead trunks and fallen lycopods got me thinking about an Alie Ward Ologies podcast where a guest was described these forests in a similar manner. They went on to say that there is a theory that decomposers hadn't evolved yet, or perhaps not to todays extent, so that the waterways of the swamps were a massive tangle of living plants, trunks and 'logs'. I've never heard this discussed, but in that type of environment it would seem that having leg like body structures to allow an fish to pull itself between and at times over all the live and dead vegetation would give it a huge advantage. Maybe it was this environment that drove the first vertebrates onto land. What do you think?
Love Alie Ward, Rachel put me onto her Ologies podcasts, excellent!! Can't see crows without remembering the crows episodes :)
@@barbaradurfee645 Alie Ward is wonderful, can't go on a road trip without loading in a bunch of her podcasts. We listened to the Crow one as well, fascinating and a little disturbing-LOL. I'm very much enjoying the Geo Girl You Tube channel as well, she does an equally great job here.
I went to drumheller in Alberta, Canada this summer. There is a huge museum there about dinosaurs, since there are tons and tons of dinosaurs fossils around from the cretaceous. the musuem has a very diverse collection, and they also go over the history of earth (although the precambrien sections is barely represented). Iin the permian section they represented dimetrodon-like and therapsids as reptile-like mammals or something like that. You're not alone doing this error if that makes you feel better xD . Reptile definition is not very clear but it does not include synapsids :)
BTW did you know they just found there a couple week ago a complete haplosaur with it's skin still intact ? That's insane :O
Wow skin! Was it just an imprint or was the actual skin preserved?? Was is re-mineralized? OMG I have to look this up now haha so cool!
Great info and contextual stuff to help understanding.
Thanks! So glad you liked it ;D
Love your videoes keep learning and making curious ❤️
As somebody who went to the Milwaukee Public Museum endlessly as a kid, seeing the ordovician reef diorama with the orthocones made my eyes light up
Yes! Gotta love the ordovician reefs! :D
You are amazing and so ambitious and intelligent and inspiring. Thank you
Thank you so much for the kind words! ;)
Excellent presentation. I learned from it.
13:20 f: I "recently" saw a documentary where they claimed the carboniferous sky was not so much blue but had a sepia tone due to the high oxygen content. If so, why?
Excuse me, where have you been in all my years on youtube? Subscribed immediately.
Thank you! ;D
Fascinating epoch. Enjoyed this a lot!
🎉🎉 I've come back from the future to watch this again!!!! I love the carboniferous!!!!
So interesting. Thanks for the knowledge
Of course! So glad you found it interesting and informative! ;)
Glossopteris looks startlingly similar to eucalyptus leaves. I wonder if they are related.
Please keep talking an teaching. I love your content.
Thanks so much for this comment. It is a very simple comment, but you have no idea how much it motivates me to read this sentence, especially now that I am growing faster and getting some not so nice opinions shared on my channel! lol
Thank you for your support and encouragement
Awesome knowledge you have! 👍
Thanks so much! I don't have that much of it, it's more just me regurgitating what's in my textbooks, but I would eventually love to have all this knowledge in my brain :D
Do you have a master's or Ph.D in paleo?
Isn't this the period of time when the oxygen in Earth's atmosphere was over 30% and that allowed for HUGE invertebrates like giant insects? Also, what life forms in this period of time were humans' ancestors and what other modern day animals are they the ancestors of? Presumably all mammals at least.
Yep! Like I mentioned in the video, the insects were able to get huge due to the increased oxygen and the amphibians that had just evolved from lobed finned fished that began to walk on land evolved into reptiles which diversified into many groups, including the therapsids that later evolved into mammals ;)
NO NOT GIANT SPIDERS NOT THE JBA FOFI
Yes
I remember the carboniferous very well. Lots of bugs, plants, and oxygen. Gave me a headache.
5:48 A single cell of up to 10 cm length??? Not a colony? A single cell?
Yes! Well, keep in mind, it is their test (or hard outer shell) that reaches that size, their cell is the tiny thing at the very center that drove the process of building that shell, but the cell itself does not reach a size that large. Foraminifera tests (or shells) have been shown to reach up to 20 cm!!! Isn't that crazy :D So cool!
@@GEOGIRL Okay, so it's not the cell itself. But that's still superweird. I've been learning a lot of really amazing things about microorganisms latetly. Bacteriophage virusses are scary! Not just what they do but the way they are built. They look like some insidious micro-weapon out of a science ficton spy movie.
@@NelsonDiscovery Yes, the micro-world is quite crazy both the things they do and their physical appearances! I feel like microbes have certainly been the inspiration behind some movie ideas haha
Really interesting stuff. Some of my favorite critters come from old times, like Dunkleosteus and Megatherium, I remember seeing them in books when I was younger. Nice to learn more about them in more modern times, thank you.
Dunkleosteus was known to participate in late Devonian, undersea basketball games.
Why is aragonite formation favored in higher Mg conditions?
Aragonite formation is favored over calcite formation under conditions where the Mg/Ca ratio is high because the aragonite mineral structure can incorporate more Mg than than the calcite mineral structure can. The reason the ions can only 'fit' in certain mineral structures (atomic arrangments) is due to the difference in ion radius (size) of the Ca ion vs the Mg ion. Hope that makes sense ;)
@@GEOGIRL Yes, thanks for the explanation
Nice channel. I subscribed!
Since a 10 foot millipede has a large brain, did they develop the ability to communicate, or have more complex thoughts?
OMG That's a great question, I never even thougth about this! From my experience, larger brain doesn't always mean smarter or more complex in the animal kingdom haha, but I don't know for sure how the millipedes brains were affected. I think that is difficult to reconstruct since their brains weren't preserved, but I am sure you are right that something must've changed.
Excellent. Thank you
Thanks so glad you enjoyed it!
I'll just be stupid and say she makes me remember what it is to learn. She's also nice to look at.
Excellent channel!
Thank you so much! ;D
As always, amazing :)
Thank you! ;D
Great summary!
Thanks ;D
geogirl it’s been awhile! Sorry I haven’t been active I’ve been super busy with college. What’s a good way to contact you? I have something fun brewing in my mind and need advice!
Hey, good to see a comment from you here! Hope you've been well, you can email me at rachelfphillips@aol.com! ;)
@@GEOGIRL Sent!
A very nice and simultaneously complete and succinct presentation! I have always wondered, though, how is it that carboniferous forests weren't regularly obliterated by terrifyingly huge and unstoppable forest fires, given the 35% oxygen levels!
Maybe that's why some of these plants grew so far apart?
Well remember, plants had just started to spread over land so Chris is right that they were relatively far apart (both the bunches and the individual trees), and also these were all swamp lands so very moist! There were only beginning to be forests in dry regions at the time and I bet they did experience forest fires often, but the swamps were too moist. Another thing to remember is much of the land was still just rock, grasses and grasslands didn't evolve until millions of years later in the Cenozoic. :)
@@MrChristianDT In my own defense, I didn't know until I watched this video that carboniferous forests were sparse, though I did begin to consider the possibility (I'm not trying to backdate my knowledge, really. Maybe. NO REALLY!) that perhaps sparse forest structure was part of survival strategy while I was composing this comment (or shortly thereafter).
@@GEOGIRL I know little about forest fire dynamics, especially at high oxygen concentrations (and I don't intend to find out by direct experience), but I'm pretty sure that even very green wood will happily combust at 35% oxygen levels (I know, I know it's not 'wood' at this time, but still...), furthermore, at least the tops (presumably where all the juicy volatiles are concentrated) of the trees would be vulnerable. Also, would great conflagrations (likely lasting just a few hours or maybe days) really show up in the fossil record? My intuition says it would, at least sometimes, but I know next to nothing about taphonomy.
As regards underbrush/grasses, I understand that these didn't really exist at the time, but.. 35 PERCENT!!! C'mon! Also, I feel constrained to point out that even you said maybe these weren't actually swamps.
Anyway, as I said, I really enjoy your content but I'm quite sure that comment sycophancy isn't the path to better content. Cheers!
@@johnwiles4391 Oh my gosh, I wasn't at all trying to be sycophantic, I am sorry it came across that way, I only wanted to try to answer the question ;)
Like I said, I think you are right that there must have been forest fires then, and I am sure they are preserved in the rock record. I just wanted to point out how moist things were because most of these newly moved to land trees and vegetated environments were incredibly moist and swampy, and I thought that fires only started in dry regions (BUT I could always be wrong I am only human, I am just given what I think is a good reason to why there might not have been more fires than today) :)
Invited this it’s really cool how our ancestry began with worm like creatures with a notochord that gave rise primitive fish which gave rise to jawed fish which gave rise to lobe finned fishes which gave rise to amphibians which gave rise to amniotes which gave rise to stem mammals which gave rise to mammals which eventually gave rise to us via the ancestor shared by rodents, Lagomorphs and primates
Very useful video 🙏
Thanks! So glad you thought so ;D
An excellent work although might not be of all the public interest. Details well cared, the presentation, including narration, is marvelous, visually appealing as well.
Terrestrial animals both vertebrates & invertebrates may often be featured for that period, the video introduces events under water, during transition & the landscape which sets up a stage for newcomers. The structure of the footage is well considered, which makes it distinct from others. Personally, terrestrial creatures in mesozoic is of principal interest. Looking forward to it.
Incidentally "before mammals" ? Could be misleading. Yes, those stem groups of mammalian lineage made a debut, but the term sounds misnomer (hair-splitting though). Thanks for your dedication!
I think it would be really great if I could travel back to the Carboniferous period and take photos, plant samples, spore cases, and seeds back with Me.🙂
That is the dream!
Great video! My PhD advisor says we can't quantify living biomass on preservation bias! Sure we see METRIC LOADS of coal, but this is actually due to the lack of decomposers at this time! Cellulose is still impossible to breakdown in your gut it's tough stuff, reserved for only a few niche organisms bold enough to evolve to break it down :D cheers!
6:40 time: "algal reeds"?
Hahaha Oops, reefs ;)
really excellent content.
Thank you so much! :)
I wonder to what extent the lower diversity of plants found in carboniferous swamps is due to sampling error because of species not fossilizing.
Thanks. Hey, I'm all for Dragonflies with 2' wing spans! But 10' Centipedes? Uh, nope. tavi.
Thanks
Of course! Glad you liked it ;)
You could totally be one of the PBS Eons hosts.
I believe Cordaites is pronounced "Core-dye-tees" from what I found online. Great and very informative video nevertheless! This is definitely one of my favorite time periods.
Great video. My favorite part was thinking about a forest of stem-like "pre trees"
Yea, I found those extremely interesting as well! :D
I thought the Devonian was part of the Late Paleozoic?
The Devonian is defined as part of the Mid Paleozoic (Early: Cambrian-Ordovician; Mid: Silurian-Devonian; Late: Carboniferous-Permian) :)
Very good - Thank You ! ! !
🙂😎👍
Ah, another channel of interest... get ye to my subscription list!!
Big 5 events?
Yep, there are 5 mass extinction events in the Phanerozoic Eon that have been recongnized as being the 5 largest extinctions of this eon. However, in recent decades, they have re-visited other mass extincitons in Earth's history any may end up adding more to that list :)
The 5 right now are the End-Ordovician, the End-Devonian, the End-Permian, the End-Triassic, and the End-Cretaceous Mass Extincitons ;)
GOOD Job GEO GIRL
Thanks! ;D
Well done!
Thanks! :D
I enjoy these videos
Hii geo girl... nice video 😇
Thanks! Glad you liked it :D
@@GEOGIRL most welcome ..geo girl..😇😇✨✨