Middle Paleozoic Life: New Predators & First Land Animals (from Tiktaalik) | GEO GIRL

[@numericalcode]

Incredible job summarizing a huge literature. Superior work!

[@AGBRMY]

Thanks

[@thoth8784]

Dunkleosteus: You can call me Dunky, sweety!

[@chegeny]

Nicely presented and well-organised overview of the Middle Palaeozoic, definitely the best on YT. Your channel is quite binge-worthy.

[@GEOGIRL]

Thank you so much! Never would've expected anyone to say it's the best on YT, but I will take it! Thanks :D

[@maryglo1]

If her videos were food, I wouldn't be so skinny!

[@maryglo1]

​@@GEOGIRLThe very best!

[@donaldbrizzolara7720]

Another thought is that the original selective advantages offered by the jaw were not related to feeding, but to increases in respiration efficiency. The jaws were used in the buccal pump that pumps water across the gills of fish or air into the lungs in the case of amphibians. Whatever the case, the feeding advantage gave jawed fish a huge advantage. As always, a great discussion Rachel.

[@briseboy]

I love all evolutionary thinkers! Consider that dermal denticles very likely evolved as adaptations, both to utility as protection from tiny predators, and shedding capacity to prevent sessile organism growth slowing them down (what a drag!). AND reduced drag occurs in the adaptation itself, a discussion involving fluid dynamics, which adds to the understanding of ALL evolution; so, back to physics . . . And, now, back again: THUS, Teeth, you might say, were originally passive protection, as usual combined with energy saving and speed increase, in that amazing efficiency-selection occurring in living organisms, UNTIL their crunch abilities (oh yeah) led to toothiness, resulting in Saberteeth, Hippopotami, and Human Hilarity, paving the way for dentists as controlling the world. And now we return you from orthodontics to Devonianshire, with a slight salameandering observation on vomerine teeth clutching our attention for a moment. Teeth, having too many utilitarian qualities, serve such purposes that, along with their jaw harp music, also give us three hands, perhaps helping us to separate from primate relatives with prehensile tails, Will "we" become more like denture-extending white sharks, finally able to reach out and surreptitiously bite our neighbor's burger? If interested ask you dentist for suitable mates to hurry this useful adaptation along. As the carboniferous may be considered as coming from incapacity to chew cabbage in a crucially chronistic course, it is a wonder that dentists did not develop earlier, precociously phylogenetically filling niches, as they do odontologically!

[@maryglo1]

Jaws was a hit for sure!😂

[@maryglo1]

​@@briseboy😂 What? What he just said!😊

[@Hellbender8574]

"DUNK-el-OS-tee-us" I think this is right. We enjoy your videos!

[@tedetienne7639]

That’s how I pronounce it too. That’s not a guarantee it’s correct, but we’re getting closer to consensus!

[@GEOGIRL]

OMG thank you! I need to consult with you before I film hahaha

[@TheRexisFern]

Everyone into the time machine, we're fixing our evolution towards the "mermaid" side. I want shell clothes and Atlantis!

[@GEOGIRL]

Yes! Let's do it 😂🐚

[@maryglo1]

And she has a sense of humor. Had me laughing out loud. Your friend, The Silkie

[@uncleanunicorn4571]

Apparently, Dunkleosteous uses a principle called the four-bar linkage for its Jaws. This is similar to how an old locomotive moves its Wheels, except the locomotive would be attached to a guillotine.

[@rursus8354]

Only 457 likes? This is one of the most information packed videos on KZbin, and people don't appreciate it!!

[@GEOGIRL]

Aw thank you! ;D

[@Alberad08]

As always, thank you very much for creating & uploading these! Really liked to watch this.

[@nicholasmaude6906]

I don't know if you like to fish, Rachel, but if you could go back in time (Ala Nigel Marvin from Prehistoric Park) would you go fishing in the Devonian? After all it is called the age of Fishes for a reason.

[@GEOGIRL]

Haha! I do like fishing, but I don't know about fishing the the Devonian, I think it would be awesome and terrifying at the same time! lol

[@Get_to_the_Point]

Another fascinating vid, you are one of a kind. Thank you for all the cool vids. I have a suggestion for you, based on what I do on my drawings. You might want to add a scale. This could be a scale bar. Or, you could do what I do and paste the same modified stick figure of a 6' tall person on all your my drawings. That is very easy and helps the viewer to conceptualize the scale of these different creatures.

[@GEOGIRL]

Very great suggestion thanks!! I will implement (but warning I have like ~10 videos that I pre-filmed before you gave me this wonderful idea so it may be a while before you actually see the change, sorry!) Again, thank you!

[@AnnoyingNewslettersPage6]

Larry Zoolander: I just thank the Lord she didn't live to see her son as a mermaid. Derek Zoolander: Mer-man! *cough* Mer-man! It might have been advantageous if we hadn't left the water. Over 3/4 of earth's surface is ocean, but we're up here squabbling over the other quarter. 🤓

[@maryglo1]

You do great work. Your voice is easy on the ears. Your appearance is also easy on the eyes. Keep being smart and thorough. I love all the information! You've got the right stuff! Thank you!!

[@GODandGODDESS]

You demonstrate a certain principle quite well....the overlapping of sciences. Your Geology videos contain extensive Paleontology. It seems like scientists are like that, and it all makes for more fun for the rest of us. Thanks, GEO GIRL

[@GEOGIRL]

YES! That is the best comment I could ever recieve, that is one of the main points I would like to drive home with my videos :D Thank you for making my day!!

[@GODandGODDESS]

@@GEOGIRL oooops, almost forgot......you're totally gorgeous too....Have a nice day, Ma'am.

[@teddyduncan1046]

Not much of a dinosaur fan but I am getting there. due to this channel.

[@GEOGIRL]

That's great to hear! I hope you continue to fall in love with everything in the fossil record ;D

[@alexandregrynagier1762]

Wow, the content of your videos is really amazing, thanks a lot!

[@GEOGIRL]

Thanks so much! So glad you like my videos :D

[@devanshshukla1114]

Your video so knowledgeable keep it up .. also ur so beautiful

[@tonikim3683]

Thanks!

[@peterbreis5407]

Fascinating! You cover the details very well. Your Powerpoint skills drive me batty though. I'm itching to redo the presentation to make it legible

[@GEOGIRL]

Thanks, glad you found it facinating! Also, which part did you find illegible? Just curious, I am always trying to improve ;)

[@lethargogpeterson4083]

Interesting. I find it easy to read, and like most of the graphic and font choices.

[@GEOGIRL]

@@lethargogpeterson4083 Thanks, I am happy yo hear that!

[@DeRailShow]

Great video, please make a playlist on structural geology too

[@GEOGIRL]

But I am not good at structure 😅 Not sure if that would be a good idea lol

[@DeRailShow]

@@GEOGIRL same here😂😅

[@tedetienne7639]

Hooray! Sundays are becoming my favorite day, with new Geo Girl videos! This was very informative. Thank you! (Note: I know you haven’t actually said you release a video each Sunday, so no pressure - especially with how busy you are. But if you do keep a weekly release schedule, I’d be very happy! 😊)

[@paulbourdon1236]

Very nice! I don't know if you've spent any time in the north-east but there was an Ordovician reef that stretched from Quebec? through NY to the Cincinnati area. About 1000 miles long, I believe. They seem to be dominated by bryozoans and rugose coral. At least that seemed to be what we mainly were finding. Also, in terms of number of families, trilobites may have taken a hit after the Ord ME but there were still plenty of them around through at least middle Devonian. The NY sites are loaded with them.

[@mariodegroote6756]

some things i would like to see in reality, would be amazing to see all in there natural habitat, but then, there are the others that scare the pants of me, stuff for nightmares... how creative nature is, it keeps amazing me every day, i always say to my son were blessed to live now(even with everything whats happening:/), so many to see and learn, so many things to explore. and we can acces it on the spot. i just love it:D anyways, respect for the upload geo girl, and i agree some names are very hard, i always see myself trying and laughing. cant win them all i always say:D greetings from belgium:D

[@NelsonDiscovery]

If we had living Hallucigenia we could test if they'd make for good hallucinogens.

[@jensphiliphohmann1876]

The very first time I read about Dunkleosteus, it was called _Dinichthys_ ("horrible fish").

[@GEOGIRL]

Aww, poor guy!

[@jensphiliphohmann1876]

@@GEOGIRL He wouldn't have felt very bad about this, I think. If some other species named us in Greek or/and Latin, they would title us Dinopithecus Avidus, I suppose. ;)

[@rickmoore52]

I can't stop watching your videos. You really do a good job.

[@tristanandriske6968]

This is a nice video I love being able to watch your videos and learn this information in such a easy and condensed way. yet they are still alot more in depth than some of the other videos I have seen so thank you. There is one thing about the evolution of fish that I believe you unfortunately have incorrect. The first jawed fish were actually the placoderms which evolved directly from the ostracoderms and still possessed the Boney armour. They later lost it when they evolved in to the acanthodians. Still a good vid😅.

[@nicholasmaude6906]

"Jaws"? Well, Rachel, Dunkleosteus wold have Jaws for lunch😉😁🤣😈.

[@bongobongo3661]

Amazing. KZbin recommended me a video with less than a thousand views

[@2RANbit]

May I suggest you watch PBS Eons about Dunkleosteus where they did a good documentary about this fish. Actually, before generally known as Dunleosteus, its genus name was once Dinichtys (spoken more like DEEN-iktys in English). Or go and look for pronuciation video clips on scientific genera names. There is even at least one amongst those pronuncition clips in which Crinoids do not sound as if they were associated with crying. It is likely to be from british English, but as it is closer to pronuciation in other germanic languages, I prefer that version. Who knows - it could even be closer to what it sounded like in ancient Greek, from which it derived. So keep in mind that other languages did NOT go through the great vowel shift as is the case in English. As for Dunkleosteus, it was a Placoderm with bony plates in place of teeth.

[@stevoplex]

Mermaids. That's freakin awesome. I like to imagine. Hendrix had a song (his best in my opinion) "In 1983, a merman I shall turn to be". Sadly gone before his metamorphosis.

[@UsmanAli-yz5zc]

Great 👍 keep up 🤠

[@UsmanAli-yz5zc]

Which university are you from?

[@LordWaterBottle]

2:30 wait wait wait, did she just say that it took HALF A GEOLOGIC PERIOD for reefs to return, but differently? We really need to make sure we don't extinct corals.

[@junebegorra]

Dunkle... D.... Dunklesaurus

[@dmj4489]

just a mutation that became advantageous.. life is so wild lol i wish we had more videos of like a deep dive into evolution of all these paleo periods.

[@MourningCoffeeMusic]

The Dunk was actually way smaller thanks to recent discoveries.

[@GEOGIRL]

Oh interesting, thanks for the update! ;D

[@wcdeich4]

Hi, did Dunkleosteus have a bony skull inside its skin with the bony plate armor outside its skin? Or was the skeleton cartilage with the plate armor being the only hard mineralized part of the animal? I ask b/c I heard some people say 1 thing & other people say something else.

[@princeshukla7661]

today I am the first who's like and comment on your video

[@GEOGIRL]

As always! Thank you for your support and loyalty ;)

[@mp-qh1um]

i have to say again love you

[@GEOGIRL]

Thank you!

[@AdrianMartinez-eg6ln]

thanks alot, helped me in my reporting

[@kslik4981]

A couple oopsies but a great video and channel!

[@JoesFirewoodVideos]

When did sharks 🦈 1st appear? #Megaladon I ❤️ GEO GIRL

[@GEOGIRL]

Great questions! Megalodon was an Eocene shark I believe (so ~30ish million years ago), but sharks in general evolved within the time frame of this video (middle paleozoic), google says ~400 million years ago, so my guess is the small ones I talked about in the Devonian were some of the very first sharks on Earth!

[@nicholasmaude6906]

It would be fun and interesting, Rachel, if geneticists could recreate Brontoscorpio Anglicus ( kzbin.info/www/bejne/fXPQfGmogLOkmKM ) by genetically modifying a suitable scorpion species. Actually now that I think about it would be nice if a Eusthenopteran analogue could be created by genetically modifying a suitable pelagic fish species.

[@camelopardalus]

dun-kel-OZ-tee-us?

[@stevoplex]

Jawed fish! Who knew? Without them, I'd probably still be a trilobite! (Not that there's anything wrong with that)😊

[@eaudesolero5631]

around 5:30 you talked about the archeological record. I studied physics, chemistry, geology, math, computers, etc .. everything we did had to be proved and shown, and backed up with evidence and experiments. you've been giving alot of information about what we think these creatures were and when, but you have not gone into the information we hve as to why we think this. and that is VITAL to good science. I have this same problem when I try to learn biology, they do not back up what they are saying with the evidence, the experiments, the observations, etc.

[@GEOGIRL]

I couldn't agree more that the explanation of why we know things is just as important as said things!! That is actually one of the things I pride myself for in my videos: I always try to explain the 'why' behind things. For example, whenever I talk about a climate event or mass extinction, I try to mention the fossil and geochemical/isotopic evidence we see in the rocks that tells us about the timing and extent of that event, rather than just describing the event with no evidence attached. That's why this comment really hit me hard, I am so sorry I failed to do that in this video! I think with some of my 'life in Earth history' videos I forget to explain the fossil evidence because as a geochemist, I tend to do so more when the evidence is chemical than physical. So in any case, thank you for pointing this out to me, I will try to be better these types of videos about this from now on!

[@eaudesolero5631]

@@GEOGIRL sorry. I can be a bit critical. But I do really like to understand the why and how... Don't forget the genetic record as well. :)

[@eaudesolero5631]

@@GEOGIRL btw ever been to Colorado? Its a cool place to see geology.

[@maryglo1]

There are some things we do not know or cannot know because there is minimal evidence

[@MrOldmanjenkin1]

Please get a proper mic and camera, webcam mics suck, even your phone would be an improvement

[@alvarogoenaga3965]

Jaws changed everything for Spielberg. Best movie ever.

[@annoyed707]

Your comment neds a bigger vote.

[@princeshukla7661]

hello geo girl how are you

[@GEOGIRL]

Doing good! How are you?

[@a.randomjack6661]

I should have studied geology to practice my diction. Some really tough words in there, but you do a great job Ma'am. 💯 Mermaids? Yeah, I can easily picture you as a mermaid. Personally, I'd rather be flying (see profile pic) 😁

[@GEOGIRL]

Thanks so much! I am always suprised at how many tough geological terms there are out there haha!

[@a.randomjack6661]

Thank you for making my day more enjoyable. You have a nice day too Geo Girl ✌

[@maryglo1]

It's English pronunciation rules and anomalies that mess up our Latin. Ah for A, A for E, E for I, O for O, oooo, for U, just like in Spanish. Emphasis on the second to last syllable. Just don't expect ME to pronounce those multisyllabic words. I'll give them nicknames like Jaws and lizards...

[@rommelfcc]

Mermaid GEO GIRL 🧜‍♀️️ 😊😉

[@princeshukla7661]

love from INDIA

[@GEOGIRL]

[@emmettbattle5728]

great video, im the same with pronunciation lol

[@girishkumarverma5863]

You look cute without makeup, love❤

[@ainaojo925]

The age of fish 🐠and the sea scorpion hunted fish 🐠

[@herosbreath6715]

“Random mutations”. Lol 😂

[@johnbaker1256]

"handish" - new word of the day

[@TonyQinMc]

Tiktaalik! Refugee of marine / founder of terrestrial

[@cerberaodollam]

Okayyy riddle me this. We evolved in the oceans. Yet, if we drink saltwater, we die. How did that happen?

[@johnvl6358]

😎

[@NelsonDiscovery]

Honestly, I think a strong human could take a sea scorpion.

[@GEOGIRL]

Oh if only we could bring it back to life to check haha!

[@NelsonDiscovery]

@@GEOGIRL Maybe we better not lol

[@jonahfalcon1970]

Dunk-lee-ah-stee-us.

[@characterblub]

Ah yes. The Dunk. Dunkie boy. Dunkster.

[@GEOGIRL]

Hahaha I am going to call him Dunkster from now on, thank you for that! ;)

[@characterblub]

@@GEOGIRL glad to be of service 😂

[@captaincodpiece3263]

I saw the film the shark was a bit rubbish didn’t think it was that groundbreaking cinematographically, oh oops sorry thought it was a film review, what a mistake to make, but I do think a geology lecturer who is also a mermaid would be a great idea for a film…now where’s Stephen Spielberg’s number….

[@annoyed707]

Jaws? Well dah duh...dah duh...

[@scambammer6102]

"maybe we would be like mermaids" speak for yourself

[@a.randomjack6661]

Latin words and names mispronunciation. Don't worry, Latin is a dead (not spoken anymore language). No one knows how to really pronounce them, except among the largest egos 🤷‍♂

[@justinjackson2588]

It kills me that religious people dont see god in evolution. This is so much more fascinating than the idea that some jackass just made things as they are. As opposed to a system that would allow for the majestic billions of years story of life.

[@GEOGIRL]

I am no expert, but I think nowadays some religions actually do account for evolution. Some of my Christian friends believe God created life at the beginning and then it evolved accordingly and then along the way he may have tweeked things here or there which is what made humans possible (at least this is how I understood it when it was explained to me, but again I could be misstating that). :)

[@briseboy]

Dear Geo Girl. Do not be overconcerned with pronunciation. Learning Latin without the horrible English pronunciations (witness : everyone, worldwide, including the original British who returned from China, pronounced cha and tea the same, in accurate oral transmission), I adamantly abhor, and REFUSE to use, nondescriptive pronunciations- I suggest that Students should stay with obvious original pronunciations to assist in easy, accurate understanding. Thus, I differ with narrowly trained medical, taxonomical and other twisted distortions. Keeping faith with compound Latinates, one is afforded optimal advantage in the taxing tribulations of memory, precisely positioning even plethorae of precambrian or paleolithic predecessors pleasurably in place. Since scores of past scientists carefully named organisms with an eye directly fixed upon the communicative value of taxonomic naming, convey to condescending critics their fallacious flatulence: Say: "la-la--la" and cha-cha-cha" should they senilely and acerbically intrude.