Why did Birds Lose their Teeth?

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Moth Light Media

Moth Light Media

Күн бұрын

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@deathsyth8888
@deathsyth8888 2 жыл бұрын
Bird dentists also went extinct after birds lost their teeth.
@pavel9652
@pavel9652 2 жыл бұрын
Beakycure services were booming ;)
@ohlookitswireddude8105
@ohlookitswireddude8105 Жыл бұрын
Dude I haven’t laughed for a week now And now its been 8 days.
@cliftonfurney5083
@cliftonfurney5083 Жыл бұрын
Them same bird dentists had stock in the bird candy business. They did ok for themselves
@luminousfractal420
@luminousfractal420 Жыл бұрын
Maybe that was it, bird dentists went private so they had to learn to live without teeth.
@BrianBadondeBo
@BrianBadondeBo 10 ай бұрын
That's true
@bioast
@bioast 2 жыл бұрын
I always was surprised by seeing the sawlike shape of goose's beak, those are not real teeth unfortunately. Another example of convergence evolution bringing back teeth but in an other form
@bkjeong4302
@bkjeong4302 2 жыл бұрын
The papillae and barbed tongues of various predatory birds and vultures also qualify: there is some support for terror birds also being like this, as the larger terror birds had enlarged palates (that support these papillae in living birds).
@ecurewitz
@ecurewitz 2 жыл бұрын
And then there are the insides of penguin beaks.
@maritasue5067
@maritasue5067 2 жыл бұрын
“Unfortunately”? If you had ever been bitten by a goose, you would be so very thankful that the real teeth are no more. I could tell horror stories about Floyd-the-Gander and his incredible ability to bite and hold on. 😳
@heilmadon
@heilmadon 2 жыл бұрын
@@ecurewitz Yeah but the penguins mouth is just to prevent fish from coming back up.
@Lvestfold4143
@Lvestfold4143 2 жыл бұрын
@@maritasue5067 geese are the most terrifying dinosaurs alive today
@seanmckelvey6618
@seanmckelvey6618 2 жыл бұрын
I like the point made at the end of the video that really, the fact that we're surrounded only by beaked birds today might simply be the result of their ancestors being the ones lucky enough to make it through the KPG event rather than a specific evolutionary advantage for losing their teeth.
@astick5249
@astick5249 2 жыл бұрын
@@Me-yq1fl ​ But its not enough to have a rapid out competition event. Toothed individuals who have a good hold on a niche will likely prevent non toothed individuals from evolving traits that can get them close to taking their niche. So they probably niche partitioned instead.
@kait3n10
@kait3n10 2 жыл бұрын
I was thinking, perhaps it wasn't just luck that helped beaked birds survive the KPG event. Since beaked birds develop faster in their eggs, it could lead to faster reproduction (since teeth take longer to develop) helping their survival. In other words, that could have been a specific advantage during the extinction event over birds with teeth. I felt that period was kind of glossed over in the video.
@astick5249
@astick5249 2 жыл бұрын
@@kait3n10 i think that one was touched on yea, but ultimately its a very minor difference. (however that difference could very well mean life or death in an extinction event)
@quitlife9279
@quitlife9279 2 жыл бұрын
@@astick5249 there are no such thing as "minor difference", any adaptive advantage is significant over evolutionary timespan of millions of years and gazillion generations, many cases much faster, even without any mass extinction events. If toothed birds were indeed more competent at any niche thus more abundant to begin with they would have survived.
@astick5249
@astick5249 2 жыл бұрын
@@quitlife9279 But when an animal already has a tight grip on a niche they are from the get go in a more advantageous position for that niche than another animal that isn,t specialized for that niche. Even if that other animal has a trait that would make it more competitively viable than the other theres still just the fact that sometimes a niche can be "taken" and it prevents others from adapting to it.
@99bulldog
@99bulldog 2 жыл бұрын
I have to say I watch a lot of paleontology channels but yours has to be one of the best. Not only is your voice pleasant to listen to, but you obviously take plenty of time for research and editing, well done.
@jashak9291
@jashak9291 2 жыл бұрын
Also its really calm and professional. Many channels like to show flashy colours with weird sound effects and wild hand gestures which can get distracting, whereas his videos are just soothing. I love that
@WanderTheNomad
@WanderTheNomad 2 жыл бұрын
@@jashak9291 Are there really that many paleontology channels on KZbin?
@koop8711
@koop8711 2 жыл бұрын
Unintentional ASMR
@kierank2505
@kierank2505 2 жыл бұрын
🌟 Wander the Nomad There are so many!
@Alyeska907
@Alyeska907 2 жыл бұрын
Agreed. I also appreciate that he doesn't drag his channel through the mud by getting political.
@Xnaut314
@Xnaut314 2 жыл бұрын
I've long proposed that an original driving force for the evolution of beaks and toothlessness in birds was a dietary shift towards herbivorous diets. Because dinosaurs did not have heterodont teeth like mammals do a fairly common adaptation seen in several herbivorous dinosaur taxa was to remove dentition from the front of the mouth and replace that with a keratinous beak. The ancestors of birds were obligate carnivores, so the first birds had sharp conical teeth as well. But any groups that started adapting to omnivory would have struggled to grab the hard, slick surfaces of seeds with a predatory mouth, so the easiest solution for a flying dinosaur would have been to remove the front teeth and evolve a keratinous beak in their place to make seed foraging easier, but retain sharp teeth in the back for any animal prey they caught. The first fully toothless birds were then likely obligate herbivores that subsisted entirely on plant material and removed all teeth in favor of a bill to optimize this dietary shift. When the K-PG Extinction happened the dynamics of the global food web changed drastically, and it's possible the only birds to successfully survive into the Cenozoic were herbivorous toothless clades. The diversity of prey species was drastically reduced for predators, and mammals were likely better at sniffing out the hiding locations of surviving insects and other tiny animals. Therefore, the more sight-oriented birds were better off foraging for plants to stay alive during the cataclysm, which would have given toothless beaked birds a significant advantage over the toothed birds that ultimately went extinct. Afterwards, all carnivorous birds of the Cenozoic were descendants of toothless ancestors and had to adapt their beaks and/or feet to become more efficient at killing prey to compensate, which we see in predatory birds of the present.
@wiwaxiasilver827
@wiwaxiasilver827 2 жыл бұрын
Wow, interesting hypothesis.
@Hotrob_J
@Hotrob_J 2 жыл бұрын
That makes a lot of sense
@mylesbartunek5920
@mylesbartunek5920 2 жыл бұрын
You know I really like this hypothesis. I could truly see this being a huge driving factor in the beaked birds we see today.
@gvasilyev84
@gvasilyev84 2 жыл бұрын
It was winter for several years after the asteroid hit so there were no plants to eat
@stephenlitten1789
@stephenlitten1789 2 жыл бұрын
Insects give a better calorific return than plants. And chitin can form very tough coatings. Beaks can give an advantage hunting insects. Just saying
@daniell1483
@daniell1483 2 жыл бұрын
"Why birds have beaks" is really the biggest question I have when comparing birds to their non-avian counterparts. Thanks for this answer!
@judeperks6612
@judeperks6612 Жыл бұрын
@@Hugh.G.Rectionx lmao
@erosgritti5171
@erosgritti5171 13 күн бұрын
God created them that way
@p0tat028
@p0tat028 11 күн бұрын
@@erosgritti5171 even if u believe that, it doesn't answer why
@PastEons
@PastEons 2 жыл бұрын
Clear, concise and beautifully illustrated, one of the best channels here, awesome work!
@norarivkis2513
@norarivkis2513 2 жыл бұрын
It's even more complicated because there were some non-avian dinosaurs who had beaks themselves, whether or not they also had teeth (which some seem to have done and some didn't). So there were birds without beaks and there were also beaks without birds.
@lordhawkridge4116
@lordhawkridge4116 2 жыл бұрын
Octopuses today have beaks too
@pavel9652
@pavel9652 2 жыл бұрын
​@@lordhawkridge4116 Insane, I haven't seen it before! There is good photographic evidence on google.
@NitroIndigo
@NitroIndigo 2 жыл бұрын
@@lordhawkridge4116 So do turtles.
@bahamutkaiser
@bahamutkaiser 2 жыл бұрын
And Reptiles can have beaks too
@norarivkis2513
@norarivkis2513 2 жыл бұрын
@@bahamutkaiser Yup! Turtles are reptiles, and it was just pointed out that they usually do.
@00crashtest
@00crashtest 2 жыл бұрын
All current turtles (taxonomic (more specifically, phylogenetic) family; who also happen to be reptiles) also have beaks instead of teeth. It looks like losing teeth and replacing them with beaks are a current theme in reptiles.
@JanetStarChild
@JanetStarChild 2 жыл бұрын
But, among current reptiles, beaks are only seen on turtles; and turtles are very distantly separated from all other reptiles, possibly being the only living anapsid lineage today.
@tuxuhds6955
@tuxuhds6955 2 жыл бұрын
Also, it helps them fly!
@justflex6745
@justflex6745 2 жыл бұрын
@@JanetStarChild birds are reptiles.Also im pretty sure turtles arent too far removed from the dinosaur lineage
@themockingdragon135
@themockingdragon135 2 жыл бұрын
@@JanetStarChild I think based on genetic analysis most phyogenists have concluded that turtles are most closely related to crcocodiles and birds, and maybe other archosaurs in general. Of course until we get a particularly clear fossil record we may never know what they actually evolved from.
@DieFlabbergast
@DieFlabbergast 2 жыл бұрын
Er ... birds are no more "reptiles" than we mammals are, even though both groups are descended from the Reptilia.
@shanevandiver8457
@shanevandiver8457 2 жыл бұрын
I love that birds ARE dinosaurs. Not descended from dinosaurs, but legitimate therapod dinosaurs. Yes, they have shed their tails and teeth and developed beaks, but dinosaurs nonetheless. To an 80s kid that's rad AF
@pavel9652
@pavel9652 2 жыл бұрын
I got it wrong a couple of times, as I refereed to birds as descended from dinosaurs, dang it! ;)
@ratreptile
@ratreptile 2 жыл бұрын
Technically though they are not mutually exclusive statements, they kindof have to have descended from dinosaurs in order to be dinosaurs.
@TransoceanicOutreach
@TransoceanicOutreach 2 жыл бұрын
'but legitimate therapod dinosaurs' - no, they are not. They are what we call 'birds'. Birds are classed as reptiles, but no normal person accepts that either.
@tacitozetticci9308
@tacitozetticci9308 2 жыл бұрын
@@ratreptile okay but that does not apply to the first dinosaur ever lol
@misanthropicservitorofmars2116
@misanthropicservitorofmars2116 2 жыл бұрын
It’s creepy, and it’s creepy knowing that dinosaurs were likely as behaviorally similar to birds. You know if a bird was big enough it would do horrific things to a human.
@jaybee946
@jaybee946 2 жыл бұрын
Feels like your quality is always ticking upward! Great video. Always enjoy them.
@leo_the_v.3847
@leo_the_v.3847 2 жыл бұрын
"The evolution of Ichthyosaurs" would be an interesting video. We always hear how Whales adapted to the sea, but i wanna know more how the reptile ancestors of the Ichthysaur did.
@pattonramming1988
@pattonramming1988 2 жыл бұрын
That would be very fascinating marine reptiles gave rise to a multi tiered food web that included large prey
@sunnyb1185
@sunnyb1185 2 жыл бұрын
There are some very interesting articles on this subject in science magazine and a few other publifications, if you're interested in that type of thing. I did a presentation analyzing the reasons why ichthyosaurs evolved significantly faster than whales and researching for it was very interesting.
@SoulDelSol
@SoulDelSol 2 жыл бұрын
Great idea
@chheinrich8486
@chheinrich8486 2 жыл бұрын
Especially bow that we knwo they went for tiny to 18 Metern Höhe just million years
@_robustus_
@_robustus_ 2 жыл бұрын
Beaks are a cheaper way of masticating food. Taking the trouble of growing and maintaining flesh and bone oral apparatus is significantly more expensive calorically. Beaks evolved in lots of non-avian creatures as distantly related as mollusks are to birds.
@magichands135
@magichands135 2 жыл бұрын
I don't really like the easier and cheap explanation, after all where is your beak? I doubt evolution cares about easy and cheap, it cares about the most fitting solution I think. Maybe these birds just had smaller pray that didn't require a lot of chewing, if any.
@heilmadon
@heilmadon 2 жыл бұрын
@@magichands135 Birds dont chew, with their beaks they filter, tear crush but not chew it makes much more sense birds evolved beaks for lightweight flight and egg development. pterasaurs had them and bats may develop them in the future.
@Faesharlyn
@Faesharlyn 2 жыл бұрын
The "masticating" happens in the crop, where they swallow small stones that do the grinding. The beak is for rooting around, finding and tearing the food, not chewing.
@krankarvolund7771
@krankarvolund7771 2 жыл бұрын
Masticating is an almost exclusively mammal trait, some other species do it, but most species can't chew, and certainly not the ones with beaks ^^ Masticating requires teeth to grind, you can't chew with a toothless beak. Most birds swallow their food whole, or tear pieces that they gobble.
@_robustus_
@_robustus_ 2 жыл бұрын
Correct, masticate is the wrong word. Consider however the various diets of birds. None of them require the extra bone, muscle and teeth that a beak and gastroliths replace. Doing away with them increases efficiency and that is often the edge one needs to out compete somebody else vying for your niche. Beaks don’t replace teeth in every situation. That’s why we don’t have them (although our dicynodont ancestors did).
@charlesjmouse
@charlesjmouse 2 жыл бұрын
"Thea earliest bird known to have existed is difficult to pin down." Ah, is that because it could fly or because it was busy catching the worm? Excellent video by the way.
@ButterBallTheOpossum
@ButterBallTheOpossum 2 жыл бұрын
This was such an interesting video. Don't stop uploading
@picksalot1
@picksalot1 2 жыл бұрын
"Much like our fingernails, a bird's beak is made of keratin and grows continuously throughout its life. Because of this, the beak must be constantly ground down-either via the bird's everyday activities or a manual beak trim-for it to stay healthy and function properly." I think that a beak may be more versatile and robust as a tool in a lifestyle where it is constantly being used. Pecking is likely to damage or dislodge teeth, and consequently interfere with eating. Nuts and hard seeds would not be on the diet. When a toothed animal looses it's teeth, starvation is not far away.
@melissagrant1649
@melissagrant1649 2 жыл бұрын
That starvation issue would really only affect most extant toothed mammal species, including us. Most toothed animals, including a few mammals, constantly shed and replace their teeth, i.e. polyphyodonts. In fairness to you, I've watched presentations by paleontologists who, from time to time, still fall back on some kind of Homo sapiens or even mammal bias when talking about other animals.
@heilmadon
@heilmadon 2 жыл бұрын
@@melissagrant1649 Or be like the rodents who teeth also never stop growing. Beaks have upsides to lead to it but also have their negatives teethed animals managed to eat a lot more plants than beaked Im still teuing to think of a beaked animal that eats leaves or grass.
@Faesharlyn
@Faesharlyn 2 жыл бұрын
*gestures toward the shark and alligator*
@picksalot1
@picksalot1 2 жыл бұрын
@@Faesharlyn Big difference in size, biting, and feeding strategies.
@Faesharlyn
@Faesharlyn 2 жыл бұрын
@@picksalot1 but they both replace their teeth throughout their lives, literally backup teeth for their backup teeth.
@SnaggalTooth
@SnaggalTooth 2 жыл бұрын
Birds aren't the only group of animals entirely beaked..., their very close relatives the turtles are all beaked as well. And they definitely didn't evolve beaks to shed weight haha
@AntoekneeDE
@AntoekneeDE 2 жыл бұрын
Thank you for this, I was completely unaware of the gestational duration effects caused by dental maturation but it certainly makes sense that being able to quickly replenish numbers and relieving parents of incubation post K-Pg would be useful even if the lack of teeth would probably put some cenozoic birds in some environments at a disadvantage against their earlier equivalents (imagine a terror bird like Titanus with a mouth full of steak knives!)
@heilmadon
@heilmadon 2 жыл бұрын
I mean instead of a bunch of small blades the current theoey is it was just micheal mayers with a knife and just rammed its beak into smaller prey
@adams13245
@adams13245 2 жыл бұрын
Mothlight, I love how you describe the process of figuring out what is a bird. It sounds so simple; is it descended from a dinosaur and flies? But then scientists have to get into the nitty gritty, with a group of supposed non bird dinosaurs that could've evolved from flying ancestors and multiple times flight evolved. No wonder scientists said "You know what? If it comes from a certain group it counts as a member. Hence, dinosaurs are amphibians and humans are fish." And then the beak, another hallmark of modern birds evolves multiple times, with the first beaked bird being much more distantly related to modern birds that a bird with a mouth full of teeth. Interesting that beaks take a whole lot less time to grow than teeth, though I suppose it makes sense. After all keratin structures such as hair and fingernail grow throughout life, while teeth, at least in mammals, don't. Though I suppose that could change with animals such as sharks with replaceable teeth... might be a good idea for an episode. Thanks for the video.
@nothingnobody1454
@nothingnobody1454 2 жыл бұрын
Rodents have teeth that grow forever
@adams13245
@adams13245 2 жыл бұрын
@@nothingnobody1454 Right you are.
@nothingnobody1454
@nothingnobody1454 2 жыл бұрын
@@adams13245 uh... I meant to say, yeah rodents are odd
@adams13245
@adams13245 2 жыл бұрын
@@nothingnobody1454 I get that. I said you are right.
@adriang1137
@adriang1137 2 жыл бұрын
Babe wake up! New Moth Light Media upload!
@TomoyoTatar
@TomoyoTatar 2 жыл бұрын
Is this is the new first?
@melgrenier3117
@melgrenier3117 2 жыл бұрын
lol for real
@zeropsaft
@zeropsaft 2 жыл бұрын
I came
@solssun
@solssun 2 жыл бұрын
original
@willisverynice
@willisverynice 2 жыл бұрын
Now that’s a funny original joke
@stevenshea990
@stevenshea990 2 жыл бұрын
Charlie: I mean, did you discover a bird with teeth in this fashion? Dennis: No, that does not exist in nature Charlie: Ok, I'm not sure about that
@anitacoogan4822
@anitacoogan4822 2 жыл бұрын
Thanks I'm always learning - enjoy.. Heard Canadian Geese have a row of hard ridges like teeth. A friend & I rescue songbirds when they migrate thru the city, they hit the glass skyscrapers or fall to the cement, most do not survive. A recent youtube video shows us in Newark NJ, the video is named( Volunteers give migrating birds injured in N.J’s biggest city a second chance ) The Raptor Trust(TRT) made video named ( Window Strikes in the Business District ) of us picking up injured Warblers. BTW last year TRT had to operate on a Heron to removed 2 of its 4 wings so it could fly better and released back to wild, I read about it in their 2021 annual report.
@feuerling
@feuerling 2 жыл бұрын
​@chu Harry It had a pair of underdeveloped wings under its right wing, possibly from an absorbed twin.
@wollin20
@wollin20 2 жыл бұрын
It's incredible how we can actually know about those ancient times, like the fact that all living birds (around 10 000 species) descend from 3 or a little bit more species of feathered flying dinosaurs whith a beak (so, basically, they were already birds) which survive the mass extinction 66/67 millions years ago. Science is amazing !
@vincentadultman6226
@vincentadultman6226 2 жыл бұрын
Honestly this and crocodiles make me giddy, it's amazing to think we're seeing crocodiles just as the dinosaurs and others have seen them Birds are soooo cool, those few species of dinosaurs have filled so many niches its crazy
@Funkiotologist
@Funkiotologist 2 жыл бұрын
@@vincentadultman6226 recently at my job I’ve been just observing birds as they go about their life, it’s so amazing to casually walk by a dinosaur 😂
@vincentadultman6226
@vincentadultman6226 2 жыл бұрын
@@Funkiotologist yeah, it's easy to take it for granted, but when you stop for a minute you can really take in the fact you're seeing the grandchildren of Archaeopteryx
@wajihbec1087
@wajihbec1087 2 жыл бұрын
do we really KNOW tho? aren't they just pretty good guesses? not that that's not impressive.
@krankarvolund7771
@krankarvolund7771 2 жыл бұрын
It's not three species, it's four orders. An order can contain multiple species ^^ It's more like there was a thousand species of birds, and only a hundred survived the extinction (those numbers are not accurate, we don't have all fossils at all). And it's the same for mammals by the way, we always say that the extinction benefited to mammals but there was a dozen or more orders of mammals before the crisis and four only survived. One of them died after the extinction, and even today, there's one big order, the placentals (us), and the two others are just a handful of survivors (the marsupials and the monothremes).
@Katze822228
@Katze822228 2 жыл бұрын
so many interesting thoughts, i love it! Especially the thought that if teethed birds did not go extinct at the K-T boundary, teethed birds might have outcompeted birds with beaks or other animals in some niches
@WhyYouAllHabut
@WhyYouAllHabut 2 жыл бұрын
I always look forward to your videos. Very calming and educational! Thank you 🙌
@johnshields6852
@johnshields6852 2 жыл бұрын
The similarities to prehistoric dinosaurs is amazing, even the big predator dinosaurs had much in common, the legs being the obvious similarity, it's an evolutionary trait that's stood the test of time.
@icycrusader1947
@icycrusader1947 2 жыл бұрын
I was kinda wondering what bird beaks were made up of, not enough to look it up necessarily. I always thought it was derived form of bone like teeth rather than keratin which makes up horns, nails, hair, and skin among other structures. Now I'm wondering if other beaked animals have keratin beaks as well or if they're different because of seperate evolutionary pressures from birds.
@heilmadon
@heilmadon 2 жыл бұрын
The pterosaurs probably had keratin sheaths coving there beak as well as some of the dinos Ive even seen one dino theory where ceratopcians had a keratin sheath on its frill.
@catjuulcultmember1631
@catjuulcultmember1631 2 жыл бұрын
I just looked it up, and octopus and squid beaks are made of chitin, the same material crustaceans use for their shells! So yes, depending on different factors beaks would likely be made of different materials :0
@heilmadon
@heilmadon 2 жыл бұрын
@@catjuulcultmember1631 That makes sense considering they are from the shellfish line but considering birds and reptiles have keratin and mammals would probably have them too if evolution ever pressured them into it.
@abduking.
@abduking. 5 ай бұрын
@@heilmadon nah i think the main factor is weight. Chitin is significantly heavier than keratin.
@travisbicklejr
@travisbicklejr 2 жыл бұрын
Outstanding video! More bird-focused content would be greatly appreciated!
@Kishiwii
@Kishiwii 24 күн бұрын
I am a huge fan and love of science and animals. Your voice is so calm and nurturing. Perfect for how much information you give. Its well above almost all other informative channels because of how easy it is to digest everything you say. I can keep up with pretty much anything but the way almost every other channel delivers information will make me feel more and more overloaded and fatigued. This here is like a symphony with how at ease but engaged it has me. Brilliant work. Well done.
@tecramos
@tecramos 2 жыл бұрын
Geese have some form teeth inside their beak and on their tongues as well.
@mrwaxwave
@mrwaxwave 2 жыл бұрын
You have a future in nature documentaries I think, such a great voice
@domib.3924
@domib.3924 2 жыл бұрын
This guy's voice is so calming, perfect for explaining evolution, especially being British.
@matje2498
@matje2498 2 жыл бұрын
Never thought about why birds don't have teeth. Great video!
@Funkiotologist
@Funkiotologist 2 жыл бұрын
it’s incredible to think what non avian Archosauria were truly like. They’re almost like made up creatures from another planet. Enormous beasts that evolved into all walks of life: flying reptiles as big as busses, feathered giants that had dominion over continents, armored titans that were built as tanks, and some of the largest animals that we know to exist literally ruling the earth for millennium, i just love it too much man it’s impeccably beautiful
@viikoreaux
@viikoreaux 2 жыл бұрын
Super stoked to have found this video as this particular topic is of very great interest to me, and information is kinda hard to find if you don’t know what you’re looking for. I’m very interested in seeing more videos on beaks vs teeth and how a beak is actually constructed and what benefits or detriments they each have.
@PygmalionFaciebat
@PygmalionFaciebat 2 жыл бұрын
I am sceptic about one of your explainations , that the birds lost their teeth because of weight. Because what you forgot to mention in your video: birds (as well as classic plant eating dinosaurs itself), needed to eat stones instead, so that the stones helped to digest the plants. Birds even today usually do that. Stones have a density of around 2,7-3 grams/cm³ .. .much higher than teeth. Losing the teeth and forced to replace it with stones in the stomach actually increases the weight of the birds, and not decreases it. I also sceptic about your second explaination : ''growing teeth needs more time in the egg to grow'' . A lot of animals today which are born out of eggs are actually born with teeth , like Lizards and Crocodiles. So i am sure the same option birds had back than, as the Lizards and Crocodiles today. Now, when we sort out these two explainations - whats left. Not a lot, but i have a theory - and its about physics. The weight of the mouth and head actually have another effect: the angular momentum. While non-flying predators only are acting in 2 dimensions, birds are moving in a 3-dimensional space in the air - means: thats a higher degree of freedom - and therefore: higher chance to miss the prey, than in 2 dimensions. Meaning: you need every piece of movement-advantage you have, to make that one hit in one split second. This not only needs very good eyes (like owls, eagles, etc) have. It also needs the most short beak as possible (remember: angular momentum of the head), and the most weightless beak as possible (the less weight, the smaller the angular momentum... the easier to move the head ... the faster headmovements can be). Tyrannosaurus rex had a big head, with a lot of weight, and therefore his head as sure didnt moved that fast, like an eagles head. But Tyrannosaurus rex didnt needed a fast head. It was enough when his body was fast enough for the big prey, and because he acted in two dimensions (walking on the ground), there was less degree of freedom for his kind prey to get away. A predator bird needs every movement advantage possible with his mean weapon: his mouth, as possible. And tooth add to the weight of his mouth...also the bones which need to support the teeth. A beak (because made of creatin) would be to soft to last a lifespan with tooth in it. Sure the headmovement with bigger head-weight could be compensated with stronger bigger neck-muscles. But birds already have that, and still take more advantage of a lightweight beak, for faster headmovements, because less angular momentum. So thats my explaination... It also could be wrong. But at least it seems as plausible for me, as the other theories you mentioned.
@catsdogswoof3968
@catsdogswoof3968 Жыл бұрын
Oh yea my point was gonna be that birds have stronger bodies than head but it seems you covered that. But just because there are toothed reptiles that lay eggs doesn't mean that disproves the teeth thing. As I think those ones gaurd the nest so that the eggs survive to make teeth.
@rickkwitkoski1976
@rickkwitkoski1976 2 жыл бұрын
Wow! I've been subbed to you for a few years now. I love your presentation. Your research is superb. You have improved so much. Thank you.
@hannahbrown2728
@hannahbrown2728 2 жыл бұрын
Broke: MLM, Multi Level Marketing Woke: MLM, Men Loving Men Galaxy Brain: MLM, Moth Light Media Thanks for another great video
@lhaviland8602
@lhaviland8602 Ай бұрын
Bespoke: Marxism-Leninism-Maoism
@hannahbrown2728
@hannahbrown2728 Ай бұрын
@lhaviland8602 Im fucking dead, giga brain joke lol
@hannahbrown2728
@hannahbrown2728 Ай бұрын
@@n31x You dont even know what woke means Id wager.
@n31x
@n31x Ай бұрын
@@hannahbrown2728 lgbt stuff?
@n31x
@n31x Ай бұрын
@@hannahbrown2728 before I start wars, let me just delete that comment.
@veryunusual126
@veryunusual126 2 жыл бұрын
And I just realized that your sub count is at 335k, which is fantastic, because I can remember when it was way lower and was thinking back then that it should be higher
@Hfil66
@Hfil66 2 жыл бұрын
I would have thought another factor that differentiates birds from most (if not all) other egg laying species is that they lay eggs with hard shells. It might be that beaks could easier break through hard shells than teeth, on the other hand that would not prevent the bird growing teeth after they broke out of the egg.
@kyoku1982
@kyoku1982 2 жыл бұрын
As I recall some reptiles have a special tooth made for breaking through their shell. They lose it shortly after hatching.
@موسى_7
@موسى_7 Жыл бұрын
Uh, egg tooth? Birds have those.
@colinmaclaughlanweir9670
@colinmaclaughlanweir9670 2 жыл бұрын
Gotta love even after all this time Archeopterix is still the oldest bird. It stands right on the line. As a kid they would draw it as a rust brown in all the books but a black and white bird is just as cool. The bottle neck the left us with just a few lines of birds and nothing else from the Dino family is just so cruel.
@stormisuedonym4599
@stormisuedonym4599 2 жыл бұрын
I look at it this way: Even if they had survived, most - if not all - would not have made it through the beginning of the Anthropocene. We were not kind to the megafauna we found as we expanded out of Africa.
@Lumosnight
@Lumosnight 2 жыл бұрын
In my book the archeopterix was drawn as colourful - yellow with dabs of green, red and blue
@rdsyafriyar
@rdsyafriyar 2 жыл бұрын
"In our day there are no longer any ideas, or they are scarcer than hens' teeth." - Louis Aragon
@veryunusual126
@veryunusual126 2 жыл бұрын
I just love your videos, you always choose topics that are totally interesting to me👍👍👍👍👍
@shattafari
@shattafari 2 жыл бұрын
I love your channel and have my post notifications turned on... and as a fan, I want to give you a tip. When you say words like "archaeopteryx" I would love for you to put the spelling in the video so viewers can research it.
@donnyjay9046
@donnyjay9046 Жыл бұрын
I am in awe of this channel. Stumbled upon from the algorithm, and I'm hooked.
@lightningboltt5437
@lightningboltt5437 2 жыл бұрын
my theory is that the birds who survived the kpg extinction ( they were all ground living and didnt live in trees) had beaks and no teeth as they fed on bugs and plants that dont require teeth but when birds started to rediversify in the cenozoic, they had permanently lost the ability to grow teeth so they adapted to new diets and environments by evolving features that allowed them to make better use of their beaks
@catsdogswoof3968
@catsdogswoof3968 Жыл бұрын
Wait so why do toothed birds exist tho
@catsdogswoof3968
@catsdogswoof3968 Жыл бұрын
In the modern day sorry
@lightningboltt5437
@lightningboltt5437 Жыл бұрын
@@catsdogswoof3968 they dont, "teeth" in todays birds is an extension of the beak
@catsdogswoof3968
@catsdogswoof3968 Жыл бұрын
@@lightningboltt5437 oh i thought these ones had beak toothed oh ok
@websdaspider8811
@websdaspider8811 11 ай бұрын
Your voice is very calming, and I love the content you are covering. Im subscribing.
@sprague49
@sprague49 2 жыл бұрын
I've often wondered how feathered dinosaurs, toothed birds included, preened, oiled and groomed their feathers. It would seem that teeth could wreak havoc on delicate plumage.
@advaithpillai
@advaithpillai 2 жыл бұрын
maybe the habit of preening developed post the KPG extinction event. The other feathered dinosaurs probably had other mechanisms to clean and adjust their feathers. Can't come up with an example though...
@quitlife9279
@quitlife9279 2 жыл бұрын
ooh that is a very good point! Lips...?
@gaufrid1956
@gaufrid1956 2 жыл бұрын
This makes a lot of sense! I love to watch the local avian beaked dinosaurs here where I live in Mindanao Philippines! Everything from the sunbirds and the finches to the raptors including the "Haribon", the "King of Birds", the Philippine Eagle!
@chrissonnenschein6634
@chrissonnenschein6634 2 жыл бұрын
It would be interesting to compare the evolutionary timeline of “birds” as compared to the evolution of seeded plants with their pollinators & to the ultimare rise of asteraceae, etc...
@rafaelmarangoni
@rafaelmarangoni Ай бұрын
Also, there’s a hypothesis that the K-PG extinction event may have selected birds with beaks. The hypothesis consists in the cloud of dust that killed most of the vegetation in the world due to the lack of photosynthesis, leaving only seeds, which can endure a longer time. Birds with beaks would have a more appropriate tool to open the seeds. And that would also explain the predominance of angiosperms.
@stefan_popp
@stefan_popp 2 жыл бұрын
It would be awesome if you could put markers w/ images on your timeline. I struggle keeping track of when what occurred and how to place times into context. Here, e.g. when which lineage diverged, beaks have been gained, teeth lost, etc. I'd also LOVE a 'review' video where you talk about one time period and sum up in which stages the ancestors of modern lineages were. What did the world look like back then? E.g. which marine reptiles were alive when birds lost their teeth?
@pavel9652
@pavel9652 2 жыл бұрын
Great video! Just to add a nerdy line on the topic ;) "Researchers have identified a genetic mutation that creates incipient teeth in bird embryos. The discovery provides a modern-day glimpse of a feature that hasn't been seen in avians for millions of years. Birds lost their choppers 70 million to 80 million years ago."
@sneeringimperialist6667
@sneeringimperialist6667 2 жыл бұрын
They lost the teeth around the time that fruit was evolving. Maybe the acid and sugar caused tooth decay, and infected teeth caused a high death rate...
@advaithpillai
@advaithpillai 2 жыл бұрын
what about predatory birds in that case? they should still have kept their teeth, would've been more useful to tear flesh
@sneeringimperialist6667
@sneeringimperialist6667 2 жыл бұрын
@@advaithpillai the ancestor birds may have been omnivorous or only ate fruit. They could have changed , later. It would be nice to see a study of stomach contents from that period.
@pompey333
@pompey333 Жыл бұрын
I heard birds lost their teeth because they were running a fight club. However, they kept it such a secret that no one ever found out for sure.
@chasduff8186
@chasduff8186 2 жыл бұрын
Much more enticing thumbnail, love your stuff
@mungobaggins8197
@mungobaggins8197 2 жыл бұрын
It seems to me that losing weight by losing teeth would be offset by the need to have a gizzard and stones. Maybe not overall, but I would think the initial evolution would be difficult.
@quitlife9279
@quitlife9279 2 жыл бұрын
Good point, but i don't believe all birds swallow stones, it is then possible that the ancestral bird didn't eat seeds or rough material that needed gizzard stones, or perhaps toothed birds also swallowed stones for digestion, since having teeth doesn't mean they can chew, so the teeth was even more weight...
@XxTheGreatDestroyerx
@XxTheGreatDestroyerx 2 жыл бұрын
I get unreasonably excited when I see a new Moth Light Media upload
@MrFossil367ab45gfyth
@MrFossil367ab45gfyth 2 жыл бұрын
Wow I never knew this! I never would've thought that the beak was important to flying. Also the idea that raptors weren't dinosaurs but were big flightless birds is cool. What a change that would be! Thank you for sharing, you have taught me so much!
@isaacbruner65
@isaacbruner65 2 жыл бұрын
Dromeosaur "raptors" were most definitely dinosaurs, but birds are also dinosaurs. Generally the loosest scientific usage of the word bird refers to avialans (a group consisting mostly of modern birds and archaic toothed birds), but not the other maniraptorans (like the dromeosaurs) even though a few of them may have been capable of flight as well.
@MrFossil367ab45gfyth
@MrFossil367ab45gfyth 2 жыл бұрын
@@isaacbruner65 , oh ok. I know that birds are dinosaurs. But the thing that confuses me is that if birds are dinosaurs, then not all dinosaurs were reptiles then.
@dibershai6009
@dibershai6009 2 жыл бұрын
@@MrFossil367ab45gfyth All dinosaurs are reptiles. Even birds.
@swian9440
@swian9440 Жыл бұрын
@@MrFossil367ab45gfyth they are still reptiles, all birds are reptiles too
@catsdogswoof3968
@catsdogswoof3968 Жыл бұрын
​@@swian9440 they have warm blood they are so powerful they escaped a group in resent times like that all reptiles need shade and have cold blood and so suaropsids with warm blood are not reptiles
@aniksamiurrahman6365
@aniksamiurrahman6365 2 жыл бұрын
Wow! I felt like lost in your story. You are a great story teller.
@travvitz
@travvitz 2 жыл бұрын
Maybe the reason all birds today have beaks is because the toothless lineages were the ones to survive the KPg extinction event, not by chance, but because their toothlessness helped them survive better in a post-apocalyptic environment? The birds who survived had to be small and agile, and this video suggests that smaller animals have increased pressure for toothlessness because of the rate of embryonic growth. This video also shows a link between toothlessness and increased agility. So yes, birds today have beaks due to only a few lineages of bird surviving the KPg extinction…but maybe it is not by chance fhat the surviving birds had beaks. Maybe it was the lack of teeth that allowed these lineages to survive.
@Apokalypse456
@Apokalypse456 2 жыл бұрын
considering that 99,99% of all species to ever exist are extinct... it is by chance. that is quite literally evolution.
@fikriasrofi5312
@fikriasrofi5312 Жыл бұрын
1. Beak make flight easier 2. Beak reduce incubation time 3. Its not clear which one came first flight or fast incubation 4. The exact answer had not been found yet
@jamesbentonticer4706
@jamesbentonticer4706 2 жыл бұрын
This is such an interesting topic.
@lsporter88
@lsporter88 2 жыл бұрын
Fabulous research. Superb presentation.
@WireMosasaur
@WireMosasaur 2 жыл бұрын
shame we don't have much data on the evolution of keratin beak coverings, it would be really interesting to see where the tipping point between keratin and teeth was in both birds and pterosaurs!
Ай бұрын
4:56 This theory is a bit distorted since developing a beak while sacrificing teeth would cancel out the weight changes
@Voltorb1993
@Voltorb1993 2 сағат бұрын
Beaks are made of keration, which is significantly lighter. They can also be made hollow/er, further lessening the weight. See toucan beaks, they are enormous, but very light.
@bortzmeyer
@bortzmeyer 2 жыл бұрын
On the "you can fly even if you have teeth" discussion: bats have teeth, no?
@MBeeGee
@MBeeGee 2 жыл бұрын
Please do a video covering each major extinction event, one that talks about the differences between each ‘period’, and one covering the evolution of humans!!! I have always been interested in these things and you would definitely do them justice!
@rursus8354
@rursus8354 2 жыл бұрын
Some scientists speculate that the beak was the means of survival during the Impact winter of 66 Mya, by being usable for eating seed.
@AnubisTheMaster
@AnubisTheMaster 2 жыл бұрын
Order 66 of birbs 👀
@ludwigiapilosa508
@ludwigiapilosa508 2 жыл бұрын
Mergansers and some aquatic birds have evolved serrations to hold onto fish, which is pretty cool. Benefits of both worlds.
@kearsargeyt8848
@kearsargeyt8848 2 жыл бұрын
I want to know the origin of pangolin!
@HaydenTheEeeeeeeeevilEukaryote
@HaydenTheEeeeeeeeevilEukaryote 2 жыл бұрын
i would love to see that too
@beneficent2557
@beneficent2557 2 жыл бұрын
Its scales are keratinized hairs, and they may go back to the cretaceous.
@anyascelticcreations
@anyascelticcreations 2 жыл бұрын
I really like these videos. Thank you for sharing. 👍
@gobanito
@gobanito 2 жыл бұрын
Can you imagine how much more dangerous Cassowaries would be if they had teeth?
@quinndenver4075
@quinndenver4075 2 жыл бұрын
I think they are so overrated danger wise. I would much rather go against one of those than say an ostrich
@Ealais76
@Ealais76 Жыл бұрын
@@quinndenver4075the problem is that cassowaries are more aggressive even if item not by a considerable amount
@crapsound
@crapsound 2 жыл бұрын
Good thing there are closed captions even though it's auto-generated. Also thanks for the vid. :D
@Eye_Exist
@Eye_Exist 2 жыл бұрын
I like the idea of raptors evolving from birds very much. Raptor claw is useless (no obvious benefit with awful minuses) when used on ground level attacks, but if the raptor can drop down on its prey from trees, then the claw damage is multiplied by gravity. due to flight birds had access to trees, which they could use on owl attacks, which would naturally spark the evolution of the raptor claw and thus make the raptor itself evolving bigger and heavier beneficial, eventually leading into flight evolving into glide and raptors evolving into supermassive individuals like utahraptor. the giant raptors still stalked their prey from trees, but now they just glided on it and struck the massive claw through its skull.
@thegameranch5935
@thegameranch5935 2 жыл бұрын
They can be used for climbing, and maybe to climb on their prey
@Eye_Exist
@Eye_Exist 2 жыл бұрын
@@thegameranch5935 the claw would work on climbing to trees and hanging from the tree trunk, waiting for the prey to come. if you meant that.
@thegameranch5935
@thegameranch5935 2 жыл бұрын
@@Eye_Exist not exactly… if a raptor find a pretty large prey it could climb on the animal using his claws and then eats the flesh (like mosquitoes but with more dying and less annoyance) You could say that the raptor can climb the tree and then ambush attack.
@Eye_Exist
@Eye_Exist 2 жыл бұрын
@@thegameranch5935 hmm, nice idea. to me it sounds like the next best thing if you can't straight up kill the target with a precise strike: sink the claw on the preys back and eat your stomach full and drop off. I just very much stand for the tree climbing, because on ground level attacks it would be so obvious disadvantage, getting tangled on roots like anchor hanging from boat when running on low vegetation, and because big claw alone doesn't increase attack power, as it's heavier to use than small claws. sprinting and climbing on a living prey from ground level would be better with small hooked claws on every finger and toe that are all even sized, without having the previously mentiooned disadvantage.
@thegameranch5935
@thegameranch5935 2 жыл бұрын
@@Eye_Exist true, i think our two hypothesis can be combined well Think about it, a large hadrosaur can easily injure or even kill a raptor, so maybe it climbed on trees to get away from dangerous animals and ambush prey It would be hard for it to get on more safe places to eat (if the raptor got on the side of the body the prey could easily throw it with his head), do you have any solution for this problem?
@kryts27
@kryts27 Ай бұрын
The theory of beaks are interesting (did other clades of dinosaurs have beaks? Yes, some did). And a beaked mammal called a platypus. Also feathers. All birds have feathers, but so did many Cretaceous dinosaurs that were not birds. Another fun fact with the Tertiary. At the K-Pg extinction, all surviving Pterosaurs went extinct, and with it, Sauropsid flight using webbing or skin membrane wings (bats use this now). Birds wings use flight feathers.
@InfinityOrNone
@InfinityOrNone 2 жыл бұрын
The argument about teeth making birds too heavy to fly has always been EA-grade BS, and could be disproven as a concept with one word: "bats."
@jmm1233
@jmm1233 11 ай бұрын
seems like geese gain more teeth , literally on their tongue
@UncleBadT
@UncleBadT 2 жыл бұрын
I'm not upset or anything, but you never touched on parrots, and I really don't know much about their history but they must have split off at some point cause of their zytodactyl toes
@Lol0Wut
@Lol0Wut 2 жыл бұрын
Another great video! The transition from reptile to birds is a facinating one. I do have a question, what music do you use for your videos?
@spatrk6634
@spatrk6634 2 жыл бұрын
FYI birds are still reptiles.
@G0L0V0L0MKEE
@G0L0V0L0MKEE Жыл бұрын
D12
@remanjecarter2787
@remanjecarter2787 2 жыл бұрын
I wonder if we could find a way to give them back their teeth
@romulus_
@romulus_ 2 жыл бұрын
we have. inducing mutations in the talpid2 gene results in chicken embryos that grow teeth.
@PomlacAvdu
@PomlacAvdu 2 жыл бұрын
"Your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should."
@gutar5675
@gutar5675 2 жыл бұрын
No thanks. I'd rather not have to worry about something flying at me to take a bite
@remanjecarter2787
@remanjecarter2787 2 жыл бұрын
@@romulus_ yes this is true, but I want a chicken that has the face of an alligator
@georgeparkins777
@georgeparkins777 2 жыл бұрын
"Crikey, mate. That emu is wearing dintures."
@lamprete
@lamprete Жыл бұрын
This makes more sense imho: at a certain period before the extinction some birds lost their teeth because they specialised in eating seeds or nuts and the beaks were better adapted to this diet, like e.g. in modern finches. Seeds were probably one of very few available food sources for some years after the extinction event, because they can survive fires and remain edible for years. Thus the ability to fly from the most catastrophic consequences of the impact plus the ability to thrive on seeds led to their survival in contrast to the non-avian dinosaurs.
@bobblacklodge
@bobblacklodge Ай бұрын
Because the designer thought beak and teeth look stupid.
@Len124
@Len124 2 жыл бұрын
Great video, though I assume by "beaks" you're referring to a toothless mouth because birds like _Hesperornis_ had keratinized beaks in the looser sense in combination with teeth.
@117johnpar
@117johnpar 2 жыл бұрын
I took them all.
@retardigrade69
@retardigrade69 Ай бұрын
Wtf give it back
Ай бұрын
1:15 was that why pterosaurs were classified as a non dinosaur?
@didyouheartheclarity8673
@didyouheartheclarity8673 2 жыл бұрын
You have got it wrong. Birds lost their teeth due to the extinction of the toothbrush tree, and subsequent tooth decay, birds lost their teeth. Jokes aside, dietary factors are almost an inevitable conclusion.
@benmcreynolds8581
@benmcreynolds8581 2 жыл бұрын
I've held a blue jay and found out surprisingly they have teeth on the back of their tongues. It was creepy to learn and see
@bonecanoe86
@bonecanoe86 2 жыл бұрын
While hiking in the woods and hearing birdsong all around me I had a thought: If you were blind, you might still think dinosaurs ruled the world.
@GadreelAdvocat
@GadreelAdvocat Ай бұрын
Beaks are easier to peck for bugs in the dirt, on leaves and grass. The flesh of jaws might get poked, lacerated and prodded leading to tooth loss and infection. Their stomach must have changed as well. As many birds used gravel to help grind down material in place of teeth. When feeding their young, teeth might harm or get in the way when regurgitating to feed them. Another advantage is to peck into, or help break apart material. Something more difficult to do with a fleshy jaw.
@stead6405
@stead6405 2 жыл бұрын
Archaeopteryx is no longer considered the first bird. While it is intermediate between more primitive bird-like dinosaurs like deinonychus and true birds, it lacked a number of traits of modern birds. Therefore, the exact transition from non Avian dinosaurs to birds is relatively unclear today.
@stead6405
@stead6405 2 жыл бұрын
@@Me-yq1fl exactly. The pinpoint line won’t ever really be totally revealed
@stefanlaskowski6660
@stefanlaskowski6660 2 жыл бұрын
Birds are not the only vertebrates to lose their teeth. Turtles, which nearly as old a lineage as birds, also have a type of beak but no teeth.
@ExtremeMadnessX
@ExtremeMadnessX 2 жыл бұрын
Also birds aren't the only dinosaurs with beaks. Every single ornithischians and many groups of theropods.
@JanetStarChild
@JanetStarChild 2 жыл бұрын
Aren't turtles much older than dinosaurs?
@approximateCognition
@approximateCognition 2 жыл бұрын
Ah, yes, the archosaur tradition of evolving a beak! Not exactly surprising birds evolved one more than once!
@samuellblake
@samuellblake 2 жыл бұрын
You have one of the best youtube channels.
@Littlekoji-df1cf
@Littlekoji-df1cf 2 жыл бұрын
Love from Finland. I love to get some biiirrb facts.
@StepBaum
@StepBaum 2 жыл бұрын
Easy to follow, great visuals, love your vids :)
@PomlacAvdu
@PomlacAvdu 2 жыл бұрын
Ok but ... why do birds have beaks? I know they're for escaping shells, but I'd love an evolutionary history on beaks too now :) Tysm for your quality content!
@_Solaris
@_Solaris 2 жыл бұрын
Moth Light Media is candy. One of the best.
@tuxuhds6955
@tuxuhds6955 2 жыл бұрын
Doing a video on teeth in avians and failing to mention geese is kind of... not cool.
@dean2211
@dean2211 2 ай бұрын
geese dont technically have teeth though. yes theyre enamel structures but not teeth
@jensphiliphohmann1876
@jensphiliphohmann1876 Ай бұрын
Birds weren't the only dinosaurs to have beaks. There were some others like the oviraptoroids.
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