When Birds Had Teeth

[@The1Helleri]

Ever been bitten by a Goose? They have teeth. Yes I know they are technically called tomia and are not true teeth. But functionally they are teeth... and they hurt.

[@youtubeguy415]

ooh

[@KlavierMenn]

And that's why there's people that use geese as guard dogs, especially in rural areas. A robber may avoid the dog... and get pecked to death by a angry geese mob

[@xl000]

my geese cut meat with those teeth.. It's not really efficient, but sometimes I give them small dead rodents that my cat killed and did not eat. But those teeth are really designed to cut grass..

[@seiyuokamihimura5082]

Yeah. They are douchebags. They used to steal my tootsie rolls when I was a kid.

[@jonhohensee3258]

TheHelleri - Are you feeling better yet?

[@Reilly444]

This is literally the best channel on youtube. No gimmicks, no wacky personalities, no non-sense; just a normal, straightforward narrative that's clear, concise and succinct. You have no idea how happy the existence of this channel, and the people behind it, makes me.

[@eons]

Thank you so so much, Reilly. I'm glad you exist, too. (BdeP)

[@Reilly444]

[@jonhohensee3258]

Literally? Not figuratively?

[@derekbauer2125]

Jon Hohensee by the context of the comment they probably meant literally

[@thespecter6416]

Boring=good?

[@WORLDCRUSHER9000]

the fact that a hummingbird is a highly derived dinosaur that has adapted to the ecological role of a pollinating insect is just mind blowing

[@LimeyLassen]

Makes you wonder what crazy stuff used to exist that we may never know about.

[@drippingpopsicle8289]

I know right

[@timothymoore8549]

To think that 99% of the things that have existed haven’t been discovered

[@Planet-Rodela-3]

The infinite symbol (sideways eight) comes from the Hummingbird's flight pattern.

[@petitio_principii]

@Mullerornis I'm not sure it's the same bat you're referring to, but there's one humming-bird-like bat that even has kind of a beak-like snout. That's ridiculous. If those things were creations of intelligent design, it should totally be sued for infringing on patents or at least design patents.

[@carrollmcpherson4530]

Evolution says "lets drop these teeth to save weight", nature says "but you need a way to grind up food". Evolution's answer:, "its ok i will just eat several rocks. Saves weight you see".

[@tedmessner6980]

Makes perfect sense.

[@spindash64]

Technically it does save weight. Teeth not only have inherent weight, but they need to be firmly anchored to the jaws, which also costs weight. In flightless animals like mammals (especially mammals since they get access to a full cutlery drawer of different teeth), the greater efficiency of teeth is preferred, especially since teeth are also very effective offensively.

[@williamjordan5554]

When only seeds were available at the end of the Mesozoic, any birds with teeth would suffer oral injuries eating seeds, thus becoming infected and eventually their species succumbing to natural selection.

[@V1z10n]

Naw, they were just sick of their dental bills. 😅

[@rufusthehunalprophet6648]

*swallows pebbles*

[@ActualLiteralKyle]

With the departure of Steve as an Eontologist, I’m here giving props for the first vid in which he graced us with his donation and presence. We love ya Steve! You’re mah boy!

[@theghostofyourwastedmoney9007]

We all miss Steve.

[@sanityisrelative]

I was listening to this half asleep in a playlist and heard "Steve!" said with such emphasis that I thought this was a new video and Steve was back. Woke myself right up before I realized what was happening.

[@ActualLiteralKyle]

@@koreyb lol heyoooooo

[@NaturesCompendium]

PBS Eons is the best

[@williambolden4325]

You bet your Archaeopteryx it is!

[@yoo7289]

Hi

[@finnchapman5435]

yep, as is your channel

[@drippingpopsicle8289]

true true

[@caliberlight2818]

Calico Jackosaur yes you are right indeed

[@jezoleum6948]

You should do a segment on 'Haaste's Eagle' . There is very little material about that super raptor out there. Normally people always talk about the Moa and forget all about the poor extinct eagle. It died out not so long ago and our own modern people lived in great proximity with them. Imagine actually seeing that monster flying up in the sky. The fear of the indigenous people. Like a jet plane. Scary. You must recreate this beauty.

[@phoenixdavida8987]

Cool!

[@theghostofyourwastedmoney9007]

Pretty sure there's evidence haaste's Eagle used to prey on earlier hominids too

[@JubioHDX]

@@theghostofyourwastedmoney9007 yup, the moa they ate would get up to 200+kg as well, much bigger than any hominin (obesity not included lol)

[@Alittlebitinteresting]

I had no idea that 1: Birds, small, flying, totally covered in feather birds, had evolved before the mass extinction. I thought that a few feathery dinos had survived and later evolved into what we now recognize as birds or 2: That there was more than one lineage that gave rise to modern birds Awesome video :D

[@holbeincrane4130]

Mammals: 5400 known species Birds: 9990 known species Conclusion: We're still on the world of the dinosaurs! (well, at least we're more on theirs than on ours)

[@spindash64]

Holbein Crâne To be fair, mammals occupy more ecological niches than birds do, at the moment.

[@Lolibeth]

there are 300,000+ species of beetles

[@10Tabris01]

@@Lolibeth We never left the carboniferous after all

[@hijodelaisla275]

"On"?

[@WynnterGreen]

Bacteria is probably the widest spread, and most voluminous set of organisms on the planet. Or viruses... if you're accept them as living.

[@RareVideosByJavierVargasTV]

“Did you discover a bird with teeth in this fashion?” -Charlie Kelly

[@treygoldsworthy1402]

Ah A fellow person of culture I see.

[@Zooollieg]

@D. Kitch One word geese

[@ambervasquez-keyes8523]

Came here to say this

[@scottydog1313]

Kallie is one of my favorite hosts of any type of show. She has a wonderful voice and her style is perfect for this type of presentation. I could listen to her recite a phone book.

[@kittyhooch1]

I remember her from years ago. There was a recipe channel I accessed with a Roku box and she was too much fun with a banana bread recipe.

[@LightBlueVans]

it’s funny you mention that because i was just thinking that! particularly with this video, i’m not sure why. i love her inflection, the energy she brings, she’s got a very warm, sweet, passionate vibe about her.

[@felipecanicali5620]

I'm a geology student from Brazil and because of a tectonic class I'm now doing a geologic time scale by hand using your videos. just wanted to thank you guys for doing this amazing job. Thank you very much, from your Brazilian fan!

[@jonathanthomas2171]

this channel, and others produced by pbs, are much needed in this day and age...and i'm greatful that there are organizations that still want to spread knowledge to the masses...thank you.

[@zedek_]

10:45 Looking at this little nugget just makes me think of my chickens; just scared, making the various warning calls for "air danger!" and "land danger!" along with the general "I'm scared!" Little thing just scampering around, trying to find a place to hide as the world was seemingly ending.

[@Ragnarra]

This is funny to me.

[@BobPantsSpongeSquare97]

Lately iv found it amusing to inform people that birds are actually dinosaurs because apparently most people don't know and I like their reactions

[@Tinyflower1]

I do that all the time! Plus eating eggs or anything with chicken in it becomes way more awesome when you realize that, yes you are eating dino eggs and dino meat!

[@KhanMann66]

Most people still believe dinosaurs are scaly monsters.

[@Tinyflower1]

KhaanMan66 they do have scales, ever seen a birds feet?

[@KhanMann66]

Cookie Panda Well my question was about how people still believe dinosaurs are 100% scales and no feathers much like Jurassic park.

[@Tinyflower1]

KhaanMan66 they also think theropod dinosaurs could have their palms facing downward thanks to jurassic park, however that would break their wrist, they had hands where the palms face each other (like if you wanted to clap, that kind of position) they also think Velociraptors where as big as a person even though they were the size of a poodle

[@theoregonguy]

I'd love a video on the evolution of endothermic (warm blooded) animals, for example when did the switch from cold blooded reptiles to endothermic avians happen? Were any of the aquatic reptiles like ichthyosaurs endothermic or were they all ectotherms? Additionally if there is any information about the earliest endotherms out there?

[@ashIibabbitt1111]

TheJeffreyJJones Interestingly, there are some fish which are endothermic. Seems like the trait can convergently evole in all kinds of species. I know some dinosaur specimens have been preserved well enough to suggest endothermic traits as well as mammal-like reptile specimens.

[@theoregonguy]

Thanks for sharing that, I knew of some shark species, and tuna that are and didn't even think about suggesting those. I think a video on this subject that covers all these different species that are endothermic would be fascinating.

[@dnwr5224]

Yes yes do this!

[@Thutil]

If you want to know when specific traits evolved, I recommend Aron Ra's Systematic Classification of Life. The series goes into a lot of detail and is great if you're interested in prehistoric animals.

[@sancheetb]

I am pretty sure they have made a video about evolution of mammals which also explains the appearance of endothermic animals.

[@citiesskyscrapers4561]

This channel is so awesome!

[@Skidd0]

Hell yeah it is

[@klyanadkmorr]

All I could think was MMMMMMmm they look tasty!

[@jonhohensee3258]

Cities - No, YOU are.

[@lnarenkumar2327]

Fortunately it still is

[@binky2819]

Here's a video topic idea. The history of paleontology itself. Old ideas we used to have about fossils, how and when we figured out that fossils are the remains of long extinct creatures and not undiscovered ones, how we figured out the story of evolution long before we even knew that DNA is a thing, etc. If I'm not mistaken, the ancient greeks occasionally found fossils of large animals, which is probably how they came up with giant mythical creatures. And native americans are known to have collected small trilobite fossils and called them "little water bugs" I think.

[@moifikea8288]

binky2819 She sells seashells by the seashore

[@alexameadow5447]

Also “dragons”

[@nabielw]

@@moifikea8288 Mary Anning!!! :D

[@richardadams4928]

Ooooohhh, including the Cope / Marsh fossil Wars! That might be worth an episode of It's its own ....

[@ominous-omnipresent-they]

Believe it or not, the Greeks were able to deduce that fossils were the remains of long-extinct organisms. Though they had no idea the age of these fossils, they were aware that eons must have passed since. They even developed their own concepts of evolution.

[@SlyPearTree]

I did not know that knowledge that birds evolved from dinosaurs was so old, it seems to me that science popularization sources started to talk about it quite recently. Or did I only noticed because thats when the same sources started talking about feathered dinosaurs? Unrelated: In French we say "Quand les poules auront des dents" or "When chicken will have teeth" instead of the English "When pig flies", chicken having teeth does not seem that improbable anymore, it already happened for their far back ancestors but also more recently in a genetic lab according to another comment.

[@rickkwitkoski1976]

+SkyPearTree - avian evolution from a group of dinosaurs has been known for quite some time. I remember 25 years ago teaching my kids that dinosaurs DID NOT all die out at the end of the Cretaceous. Small avian ones survived. At 5 years old at the beach and seeing a seagull my daughter remarked: "There goes a flying dinosaur!"

[@irkendragon]

yeah, it's pretty old information. Just seems to take forever for scientific knowledge to leak into the popular consciousness. Which makes one wonder what other interesting things are currently known in the realm of modern day papers and scientific journals that we're missing out on.

[@rickkwitkoski1976]

+PaperDragon OR: commonly heard misunderstandings of science that the public hangs on to even those misunderstandings have been completely debunked. Take the "Coriolis Effect" on the direction of water swirl in a basin or toilet bowl or whatever. It CAN (and has) been shown that in a very controlled setup, you will see the swirl in opposite directions in the north and south hemispheres. But there is NO WAY that you can see it in a standard basin, toilet bowl, whatever; because the shape of the basin and interfering fingers and other objects create so much background "noise" that you can't make a conclusive observation. And this is just a minor misunderstanding.

[@samuelaraujomedeiros6682]

I think the problem is that that information is not very well disclosed out of the academic world. Some people still don't even "believe" in evolution...

[@hyzercreek]

We say "rare as hen's teeth"

[@charliesmith1358]

Funny how falcons went back on this somewhat when they evolved their tooth like beak formation. Still considering it is just a part of the beak, not a seperate structure like actual teeth, it most likely doesn't impact the incubation time all that much. Very interesting episode though!

[@falcoperegrinus82]

There's also birds like mergansers that, in a way, re-evolved teeth in the form of bill serrations and ducks that have very fine, sieve-like "teeth" that allow them to filter food from water.

[@fubberpish3614]

not to mention the pelagornithids, massive seabirds with pseudo-teeth (technically pointed projections on the beak). they're extinct now, but existed up until extremely recently, only disappearing about 2.5 million years ago - the last surviving species were still around when Homo habilis existed! despite their similarities in appearance and niche to albatrosses, pelagornithids were actually more closely related to fowl, like turkeys and ducks.

[@blergh9416]

When Lions and Bears Clashed About Cave Lions and Cave Bears

[@KhanMann66]

Hell yeah.

[@marioandloveyaplushmasters3374]

When lions and bears clashed? Ancient Greece.

[@Infernoraptor]

@Desk Goji Actually, that got me thinking: why are there no bears in Africa? As far as I know, the only African bear was a brown bear (sub?) species that was killed off in the 1800's. Did bears evolve elsewhere, EG, the new world? If so, why did they largely fail while their canid cousins did better (jackals, wild dogs, golden wolves, foxes, etc)? In fact, it'd be interesting to see how/why the different groups of carnivorans (specifically the apex predator groups; cats, dogs, bears, and, to a lesser extent, weasels, mongooses, and hyenas) came to rule their respective territories and niches? Did these carnivoran branches arise in the same regions and over what time scale? Were the first pinnipeds (seals) weasel-like or bear-like? Why did both caniformes and feliformes develop long-bodied hunters with the musteloidea (weasels) and mongooses (herpestidae)(respectively)? That could be at least an episode.

[@Naiadryade]

Infernoraptor, that is a wonderful episode suggestion. I am so interested!

[@hypercumstone44]

Desk Goji yesn Please!

[@icemanTK]

I'm not really sure why, but this episode gave me a strong feeling of peace.

[@reinaldofuentes2054]

I am so thankful to have discovered this channel! It has been a breath of fresh air and a sorbet in a world growing ever crazier. Thank you and please keep creating great, informative, educational content like this. It is sorely needed!

[@Rhynez]

Is there anything known about how pterosaurs developed the ability to fly? It kinda came to me that often it is talked about how birds evolved but not pterosaur

[@traceursebas]

Henry B yes, a video on the evolution of flight in pterosaurs would be awesome

[@DanielSanchez-ew1js]

unfortunately, we know next to nothing about pterosaur evolution. Their ancestors are completely unknown to science.

[@KhanMann66]

Well we don't know. The earliest ancestors already knew how to fly. There's no transitional fossil currently available.

[@Meckro]

Aliens, that’s how

[@minte1972]

Just a guess, but flight could have developed from some kind of early pterosaur ancestor that glided. Maybe an aboreal or coastal animal?

[@GhaziRostom]

every episode just blows my mind

[@JacksonWheat]

And there have also been many other stem-birds found in recent years: Xiaotingia, Aurornis, Anchiornis, etc.

[@fee7013]

I know that you already made a video about smilodon but i would LOVE to learn more about other big extinct mammalian predators like andrewsarchus for example- there aren't really any documentaries or videos about this topic Eons team you are doing such a great job thank you! xxx

[@JeffSans]

I am in awe every time, the way she speak takes me back millions of years ago!!! Amazing PBS Eons!!!!!!

[@mrpalaces]

Will ever a quirky paleonthologist name a genus "paleobirb"?

[@delfinaanamiodi12345]

8:49 I love how the sad music starts when she says they where doing fine untill it ended in extintion

[@thecreature7608]

Interesting topic. Looking forward to learning about it. If I may suggest a future topic, perhaps a video on how metamorphosis evolved in insects mostly, but also frogs and such. I think that and s video on things like gorgknopsis or kaprosuchus would be awesome to learn about. Keep up the incredible work eons team😄👍

[@wienzard93]

I second this! please cover this topic.

[@search895]

I like the detail that perching claws come from life in the trees. Our hands as primates, with fingers that close circularily to grab, come from similar reasons, but i think with more different origins. we see rodents, otters or racoons also have fingers able to grab and function as hands.

[@alfredogonzalez8735]

Can you talk more specifically about the microbiome? Where did these bacteria come from and how long have they been with us

[@sagarverma369]

Alfredo Gonzalez Actually microbiome is an aquired thing.. which a person start gaining just after the birth because enviroment is full of microorganism, place where they can survive...there they will grow.

[@alfredogonzalez8735]

sagarverma369 technically everything is “acquired” but we have developed physiological adaptations to have certain bacteria in our guts rather than others

[@sagarverma369]

We haven't developed for them to survive...few bacteria have developed adaptations to survive within us. Even commensal bacteria can cause disease in us if the person is immune compromised, this is because we haven't adapted anything for them to survive in us.

[@LuisSierra42]

How so man, all bacteria were before all eucaryotes. It's not possible to have a clear view of the evolution of bacteria because they were so small. All the clues we have come from their chemical footprint

[@alfredogonzalez8735]

You guys just haven’t read the data on the microbiome ... out of the thousands of bacteria present in our gut all human beings fall into 1 of 2 enterotypes ... either a higher prevalence of bacteroides species , or a higher prevalence of prevotella species... recent data has shown that the short chain fatty acids: butyrate, acetate, and propionate function in the suppression of inflammation and cancer ... those with higher ratio of prevotella create more of these short chain fatty acids which suppress the immune system... when these bacteria are absent, our immune system is ramped up because it lacks the short chain fatty acids so it assumes there is a different bacteria present.... those with more bacteroides also have higher rates of chronic diseases like colon cancer www.ncbi.nlm.nih.gov/m/pubmed/25198138/ our body has developed physiological adaptations to have certain bacteria live within our bodies as opposed to others

[@veggieboyultimate]

The enantiornithines probably lived in the poles too

[@richardadams4928]

My cockatiel, Baby, says thank you for making a video about his grandparents.

[@Goldenrod6901]

Editing mustake at 4:32 "in their wrist" and highlights the "finger" joints

[@catherinehubbard1167]

This is an especially excellent episode. Well done. Thank you!

[@takenname8053]

12:06 First sightings of Steve on Eons

[@LivingParadox87]

This, like all things on this channel, was incredibly fascinating. I love this channel so much! Thank you!

[@jcortese3300]

This, with the one on cetacean evolution, is my favorite episode so far!!!! I've been fascinated by this whole subject for ages, and I'm so happy to learn to current state of thinking about it! THANK YOU for addressing this topic!

[@Getschakter]

How did parthenogenesis became a thing and why is it so rare?

[@jonhohensee3258]

become

[@AliothAncalagon]

Would make for an interesting episode. Especially since the very new marbled crayfish seems to get along quite well with it.

[@darkmuffinmx401]

This whole channel is very interesting but this particular episode is great, I didn't want it to end. Keep it up, guys!

[@prestonang8216]

‘I hope you enjoyed this episode! ( And all the difficult words I had to say...’ I’m dying!

[@0192123]

10:15 wait... Galloanserans which were semi-aquatic include ducks and chickens!? are you telling me ancient chickens used to be aquatic?! please PBS Eons explain this!

[@UrsusMarior]

I LOVE this channel, thanks for these amazing vids. It would be great to hear more about the Chicxulub crater. It's apparently the second largest impact structure on the planet.

[@reyesjoe]

At 2:02, what you identify as Ichthyornis is the skeleton of Hesperornis.

[@angeliquebarbey8340]

This is a most informative video! The evolution of the birds from the Mesozoic is more multi-faceted than one may have previously expected it to be!

[@dethengine]

Haha! As I was listening to you, I thought to myself, "Does she just know all those names?" You're a wonderful speaker, and I love watching your videos!

[@Diepzeevis]

I love these videos. So much amazing information. And the content and way it's presented is so integer and passionately brought forward it almost makes me emotional (almost?). Thank you all so much.

[@becauseimafan]

Cuteness alert @ 7:47!! So adorable!! Excellent video, as always! ♥️

[@DaiBaNANA]

Think about making a video about the evolution of cactii!

[@aaronmarks9366]

Yesss, awesome idea, cacti are amazing

[@sergemarcoux7762]

It is so easy to listen and learn with you! Thank you for your great work and keep on your great work!!!

[@UnwrittenSpade]

This channel blows my bird mind, so interesting! Love it

[@ivanstanojevic964]

God bless this adorable person and her soft beautiful voice

[@somedude140]

Minor correction: new genetic tests are pointing towards the tinamous being a part of the ratite group themselves.

[@ThunderJunkOC]

Dang Micro-Raptors! Stop knocking me off my mount!

[@michaelcipriano8963]

I would love to know more about sea scorpions!

[@minte1972]

An episdoe on eurypterids would be gud

[@aaronmarks9366]

They now have that! I love this channel

[@rockinbobokkin7831]

Ooh! A long one! Love you PBS! Thanks for always working to make education fun!

[@londonjackson8986]

Finally! Someone has made a video about Mesozoic Birds! Edit: And it''s a great one too!

[@mr88cet]

Excellent, excellent summary! Thanks a bunch EONs!

[@sebastiaandekoning8538]

Is it possible you guys can make a video on geomagnetic reversal? And what happend to life on earth? You guys really are amezing!

[@ashIibabbitt1111]

Sebastiaan De Koning *life

[@bratwurstmitbiryani]

*amazeng

[@epicfromepicgames8222]

Amazing*

[@epicfromepicgames8222]

@@bratwurstmitbiryani amazing*

[@maxkuzmin609]

I think this channel is the best thing I have ever found on KZbin. I would love to learn more about cephlapod history, really early ones like orthocerida are kind of surreal seeming to me.

[@andrep4805]

Don't you know I'm at work? I stopped everything to watch this worthy video!

[@shenghan9385]

I don't. Don't you think it's little wrong to watch you tube st work?

[@Horzuhammer]

Awesome coincidence! Discovered this chan only a few days ago - when I saw your playlist, my reaction was more or less 'goddammit, I'm not sleeping tonight.." :D After catching up, the video I still wanted to see was exactly this one! Thank you for your work guys.

[@tbage2210]

Honestly I wish KZbin would stop advertising KZbin premium to me, as if they deserve any more money when they choose to ignore probably the most "family friendly" content there is, eons.

[@Radi0ActivSquid]

I love this channel so much. It brings me an incredible amount of joy with every episode that comes out..

[@scottwooster4102]

these videos are great. Would love to get more detailed videos on some of these topics.

[@dentoncrimescene]

"Side to side, not up and down" loved the actions.

[@IceSpoon]

History of birds is basically the story of the most successful (or damn lucky?) ground-dweller chordates ever :O thank you for this video!

[@NorthernChev]

I absolutely can not get enough of this channel.

[@nightshark088]

Can u plz do a vid on pseudoteeth like the ones Pelagornis sandersi had

[@atomicwinter31]

I still want you guys to do a huge project on alot of ancient creatures, clearing up misconceptions and showing how or why it acted like it does.

[@firethylacine1976]

The idea that there was a time when pretty familiar birds existed alongside dinosaurs is so weird. It would feel somewhat normal until you see a T-Rex in the distance

[@anagjini7111]

I love this channel ridiculously. I get so excited every time i get notified on a new video that one day I might just get down on my knee and propose.

[@canowhoopass1949]

I had dinosaur for thanksgiving. Yabba Dabba delicious

[@mayajade6198]

This episode was a wonderful summary of avialan evolution in the Mesozoic. So many people just leave it at "and then the dinosaurs that survived turned into birds," but there's a whole history of birds before the K-Pg extinction that most people don't know about. My one complaint is that the reconstruction of Archaeopteryx that you guys used here was... really, really awful. Like, absolutely horrible. We know that paravians had feathers that were more or less identical to those of modern birds; you would probably have had to look very closely to tell that they weren't actually modern animals. They were certainly not horrifying lizard monsters like the one shown in this video.

[@HunterNicholsKingOfOmnitron]

Tell us about Megaraptorian evolution?

[@riot2136]

Comi Raptor we know next to nothing about mega raptors compared to other dinosaurs. It be cool tho

[@OlWolf1011]

All not hard to imagine, as I watch my chickens, turkeys, and guineas run across the pasture - reminiscent of the gallimimus stampede in 'Jurassic Park'. One of the things I love about keeping them is - "I own Dinosaurs!" 😄 Oh - get bit by a goose, and you realize they have serrations along their jawbone that act as teeth and can make you bleed! Folks say birds lost their teeth - I say "Not all of them!" 😉

[@TamarZiri]

Eons are the best!

[@merveilmeok2416]

Better than the neons?

[@gromann]

This is quickly becoming my favorite channel..

[@turmunhkganba1705]

Could you cover the evolution of blood?

[@angelomastri1416]

Can you imagine what a Cretaceous woodland would sound like? Equal parts tranquil and nightmare fuel lol

[@Twofacemockingbird]

Love this shoooooowww!!!!! What do I want to learn about next? Polar dinosaurs! Like Leaellynasaura and Nanuqsaurus! What did they look like? How did they handle the daylight situation near the poles? How cold was it when they were alive and what traits did they evolve to handle the climate they were in?

[@vivimaze]

I love settling into to watch one of your videos after a day of study, your presentation is so relaxing (Also your nails are so pretty)

[@JPMitchell31721]

Small nitpick here. You said that a theory was proposed, but theories aren't proposed. That's hypotheses. Theories are conclusions arrived at and agreed upon by many scientists independently.

[@shenghan9385]

I disagree with you. I don't think there is such a strict distinction between a theory and hypothesis. Not to mention that a theory can at any time still be subjected to doubts and tests. Or they may be built upon and altered as newer better facts, observation, knowledges, and other possible variables come to light. A theory is in essence always a hypothesis of some kind.

[@JNS512]

I enjoy watching Dinosaurs out my window when I place seeds on my deck.

[@S0LAAARRRRR]

i swear geese are our raptor they got teeth feathers wings

[@richardblazer8070]

Geese don’t have teeth

[@MonsieurWeevil]

​@@richardblazer8070But they have the next best thing.

[@nickush7512]

A truely top shelf presenter, so enjoy your videos, thanks.

[@ashIibabbitt1111]

Saying birds evolved from dinosaurs is like saying chimps evolved from primates or crocodiles evolved from reptiles. While technically true it's misleading as it implies that birds are separate from dinosaurs, chimps are separate from primates or crocs are separate from reptiles. A more acurate thing to say is that birds evolved from theropod dinosaurs or they evolved from non-avian dinosaurs.

[@brendarua01]

So what you're saying is we need to point to the most recent common ancestor. In that case we implicate both birds and dino.

[@ashIibabbitt1111]

Brenda Rua Birds are classified as Avian-Dinosaurs. Birds aren't just "evolved from dinosaurs" birds *ARE* dinosaurs, just as chimps ARE primates and crocs ARE reptiles.

[@andrewchelton6710]

So it is the thought that a square is a rectangle, but a rectangle is not a square?

[@patrickmccurry1563]

Cladistically, we're all fish. Most people do not use cladistic terminology.

[@andrewchelton6710]

Patrick McCurry is there a video explaining what you just said?

[@yseson_]

This was lovely, well presented and succintly explained thanks for enrichment.

[@andresamador9855]

Where did flowers come from?

[@themajestickea1037]

Andres Amador They already did a video on that :) kzbin.info/www/bejne/Z2TEhqJrm6qdhLs

[@jonhohensee3258]

Andres - Fairies.

[@richardbidinger2577]

You guys rock. Incredible video. Always wondered where birds came from, now we know. PBS EONs is awesome.

[@dersitzpinkler2027]

Never been so early! Hello to my favorite science channel!

[@dyslexiusmaximus]

Omg yes! I've recently realized that something that faciantes me is how dinosaurs became birds. I've found it hard to find information on the subject but no worries because PBS eons has my back haha. Thanks

[@AxleLotl]

As an ARK player, I truly love this vid x'D

[@SomeoneCommenting]

Geese and ducks still have these small barbs in their beaks to pull grasses, and they resemble rows of very small teeth. When a big goose bites you it is quite painful.

[@brfisher1123]

They should really talk about the entelodonts!

[@unoriginalusernameno999]

If, by natural selection and evolution characteristics get enhanced (like scales into feathers and limbs into flippers and fins) how then are unwanted characteristics gotten rid off (like tails in humans, the remnant being the bone called cocytus)?

[@bratwurstmitbiryani]

You need to understand how natural selection works then you will stop asking such questions

[@metal123498]

Eyy just discovered this channel today and subscribes and immediately a new video, nice!

[@hardland]

I' ve found your channell a few weeks ago, and I' going through it from older to newer And so far, this is my favourite one.