How (Some) Plants Survived The K-Pg Extinction

[@YesmynameisBob]

As an evolutionary botanist and population geneticist, let me just say that I both love and also hate genome duplication events. At least half of my research time is accounting for potential polyploidy.

[@JohnCooper-gm6mn]

As an angiosperm, I concur.

[@diplosbae]

I never made the connection between invasive plants and polyploidy, pretty interesting. I always figured polyploid plants were more resource-intensive as their fruits and flowers tend to grow larger (strawberry, rose)

[@mimisezlol]

That sounds like so much work. My condolences

[@travisjacobson2334]

As a polyploid, you’ll never find me.

[@throwawayacc2514]

how do i get this job

[@krupam0]

I get that plant evolution might not get too many clicks, but I think at some point you really should do a video on the evolution of grasses and grasslands, seeing how it seems to be a relatively recent occurrence and how it drove the evolution of many species, including but not limited to humans.

[@fyr3st0rm35]

Evolution might not get clicks but it gets chicks, ayoo. Why am I like this?

[@Animallovercomedian]

That would be great!

[@ratillecebrasquedubitantiu4451]

But grasses evolved more than 65 million years ago

[@psilocylence]

Plants are marvelous beings. The fact that some of them can grow from a cut node, or even a single leaf is nothing short of amazing

[@baishalideb5565]

infact many of them

[@slimjimshady0]

That art of the plants growing out of the sauropod skull goes HARD

[@karmaarachnid8345]

Another role for polyploidy in the evolution of plants has been that when two different polyploid species hybridize with each other the hybrid offspring get a full diploid set of genes from each parent species. A hybrid of two non-polyploid plant species may not even have the same number of chromosomes from each parent so it may not be able to carry out meiosis. This means that polyploid hybrids have a better chance than most hybrid plants of being able to produce viable offspring of their own and thus give rise to new species.

[@joshyoung1440]

Like I'm gonna listen to an aye-aye about plant genetics! :P jk, thanks for the info, quite cool

[@wordytoed9887]

I thought organisms of two different species cannot create fertile offspring. Am I mistaken?

[@lazzorfrogz2973]

@@wordytoed9887 that is the case with animals but plants crossbreed very readily hybridize species that are closely related to them and the hybrids are almost always fertile but there are few that can’t produce seed especially if they were a result of a cross genera like fatshedra which is a hybrid between a fatsia japonica and hedera helix or Leyland Cypress many landscape plants are hybrids and they are capable of producing viable seed you would be surprised on the amount of plants grown are hybrids

[@adamseroka5609]

Aaaaaaaand we can exploit that to get our seedless triploid Cavendish!

[@gamingpanther7773]

​@@wordytoed9887 If it is followed by whole genome the problem is solved. Think a plant AA is hybridise with BB. The new plant AB is sterile and can multiply just by vegitative propagation but not seed. But if the whole genome in duplicated it becomes AABB and problem is solved. Modern wheat has duplicated genome of 3 grasses so they are allohexaploid, like AABBCC.

[@kimwasalreadytaken]

I just want to take a moment to say thank you for adding proper subtitles! It means a lot to those of us who rely on subtitles to fully understand and enjoy the video. It's appreciated. Thank you.

[@nicks1451]

Wow I always assumed plants survived the extinction by remaining dormant as seeds underground. I had no idea that they were actually thriving their way through the event

[@brianreddeman951]

Well I wouldn't call it thriving. Ferns and fungi flourished first with Angiosperms having a rough time of it at first.

[@edmondantes4338]

Surviving underground must have played a part also.

[@newq]

The video said nothing against surviving in a dormant state, my dude. The process described in this video took a long time. Polyploidy is part of how they bounced back, not how they survived the months and years immediately following the extinction event itself.

[@bjnslc]

@@newq the title however says otherwise, misleading as titles are often crafted to be.

[@Silverstreamhomecrafts]

Me too!

[@SweetBerryWine3000]

More plant content please! This was absolutely fascinating! I've always wondered how plants made it through the K-Pg extinction event. Thank you evolution and polyploidy. And great job as always PBS Eons. ❤🌱❤

[@FishHeadSalad]

Agreed. I always assumed that since seeds and plant spores can lay dormant for decades and beyond yet still stay viable, that that was how trees survived.

[@scvcebc]

@@FishHeadSalad All that dust and ash probably took a long time to settle, so there may have been hundreds of years of dimmer light and cooler temperatures. Some American Chestnut trees have been sprouting from old roots for a hundred years now, the leaves and branches keep getting killed by the Chestnut Blight, but each year, just enough energy gets back down to the roots to try again the following year. So some trees might have been able to hang on until enough light returned to allow real growth again.

[@BrianEthridge-wk6hz]

I just figured it didn't get all the seeds, and they survived that way. I didn't figure it was this complex so to speak. A seed is way more prone to survive high temperatures than flesh or a plant.

[@earthknight60]

Many ferns have extremely large genomes and have long been assumed to have gone through several genome duplicating events. Polyploidy is not just limited to angiosperms. Recent work by Cheng, et al 2023, *Revisiting ancient polyploidy in leptosporangiate ferns*, investigates this in more detail.

[@king_halcyon]

"leptosporangiate" what does that mean? I know the sporangium but what does this technical term mean?

[@earthknight60]

@@king_halcyon "The Polypodiidae, commonly called leptosporangiate ferns, formerly Leptosporangiatae, are one of four subclasses of ferns, and the largest of these, being the largest group of living ferns, including some 11,000 species worldwide." What you get if you look it up.

[@ironsnowflake1076]

Yet my plants struggle to survive me..... great vid as always.

[@B2WM]

We are more deadly than the meteor, at least to plants.

[@kellydalstok8900]

You don’t have a garden? Because some weeds can survive just about everything you throw at them.

[@B2WM]

@@kellydalstok8900 True, dandelions are floral cockroaches. (And even those can get patchy in my lawn.)

[@Gr_ub]

I study plant genetics and diseases and love when you guys do plant videos! Any chance we could get a video about ancient plant pathology??

[@LeoDomitrix]

Adding my vote to that! Grew up on a farm, so plant ailments were always something we were aware of...

[@brittaistheworst7523]

I would unironically love a video about the history of bananas

[@ernestonasution8693]

Greetings from Nashville🙏 I'm 20 years old now, and I've loved watching these videos since I was 14. I wonder what percentage of the viewers here are/were researchers in anthropology, paleontology etc. Thank you, PBS Eons, for fueling my fascination!

[@user-yw9mw9hv8o]

Photosynthesizers are the basis of nearly all ecosystems, they deserve more credit. Cyanobacteria really sent earth on the path to becoming what it is today. Plants are the most strange and fascinating to me. Everytime we talk about eukaryotes we mention how amazing mitochondria are and where they came from, but plants did the endosymbiont thing twice!!! Lastly, Lichens, they're really overlooked too for how fundamentally incredible they are as composite organisms. Love the plant episodes! (Even if they include record numbers of nonsense 3D renditions of DNA)

[@MaddoxLightning]

Thank you again for recognizing native people communities and land.

[@tuckercaldwell4965]

It blows my mind how much we've been able to learn about history in deep-time through genetics in recent years. More plant content please!!!

[@christopherb8017]

Polyploidy (at least an initial tetraploidization event) are often also seen in many tumour types (e.g. ovarian, esophageal cancer etc.) for largely the same reason. There ain't no meteors hitting the tumour, but it helps them grow out and evolve. Your channel is ⚡⚡⚡

[@Uluwehi_Knecht]

Colchicine has been used to induce polyploidy in agricultural and ornamental crop breeding, and is still used today to treat gout. Today the herbicide Oryzalin is favoured for the former as it is comparatively less dangerous to human cells than colchicine. I wonder if there is anything interesting going on there with tumour development?

[@aplaceinthestars3207]

I wasn't expecting a double-dose of DNA to be the answer to the video's tagline. It was fascinating though a little complex, so I hope there's more plant videos lined up!

[@miketacos9034]

This is one of those questions you never think to ask, but then wonder how you never thought to ask it.

[@larsnielsen1606]

This has been my favorite of all PBS Eons videos. Thank you for the curation of such interesting material. Thank you for the presentation style. It is something that my whole family enjoys.

[@yomogami4561]

glad to see this as i've always wondered how plants were around after the extinction event and also how herbivores survived after the event

[@scvcebc]

Most of the surviving land animals were small generalists that could eat seeds and/or insects. The insects were often detritus consumers.

[@yomogami4561]

@@scvcebc true but descriptions of the devastation made it seem like nothing could survive the 'darkness' except maybe lichens and fungus. i've always doubted that for others to survive

[@FRMJD1996]

Abilities and Events such as these, are what I am referring to when I think about real magic. I never knew about this before your video and it is utterly amazing. What also strikes me about it, and something I am a little surprised that you didn't make note of, is how this did not only save these plants from annihilation. That in fact, in the aftermath of the Extinction Event, this must have allowed the surviving animals such a reprieve by allowing herbivores to have some food sources once again and subsequently the surviving carnivores as well. To think how this must have played such an integral role, if not a decisive one, in the survival of so many lineages of life following the KT event. Astonishing, Absolutely Astonishing🤩

[@Jamachlee]

I love how much Kallie always appreciates the jokes at the end! She always gets so tickled 🥰

[@jso6790]

I had the exact same thought at the end of this video.

[@ThePwebb]

Yes, but this reaction was particularly adorable. So much so I had to fanboy my way through the comments to see if any others thought this was as noteworthy as I.

[@Games_and_Music]

I welcome more plant videos! These are too rare, compared to the animal videos in general. Would love to see videos detailing the evolution of many species of plants and fungi, because usually we only get a compilation or one-off and that should keep us busy for some years. Chris Packham used to have a great show called "Secrets of Our Living Planet" and it had a great mixture of animals and plants and the workings of the planet combined.

[@piotrkowalewski1111]

Thank you so much for today's episode! Your videos about plant evolution are inspiring me during my environmental classes with children!

[@johnelliott7850]

Nice to see a video about an issue affecting plants (instead of yet more animal stuff).

[@TonyNaggs]

Thanks for explaining polyploidy!

[@punditgi]

My favorite presenter of all time! She rocks the casbah! ❤😊

[@SurfbyShootin]

PBS Eons always delivers the goods!

[@nothanks800]

One of my favorite channels and presenters on KZbin. Keep it up all!

[@helenofargos]

Wanted to pop into the comments for a sec to say that the editor/animator did a great job on this episode! Those visuals really helped connect the dots in places where the concepts were a bit harder for someone who barely passed bio (roughly 12 years ago...yikes) to keep up with easily.

[@newyorknewart]

OUTSTANDING EPISODE! I REALLY LIKED GOING BROADER THAN JUST DINO'S, ANIMALS, INSECTS AND REPTILES. PLANT EVOLUTION IS FAR MORE INTRESTING AND UNIVERSAL. AND YOU ARE MY FAVORITE PBS EONS HOST! 🥰😇😁

[@damonroberts7372]

Thanks for the paleobotany content! I know dinosaurs and the cenozoic megafauna are exciting, but there's no ecology without plants.

[@Pottery4Life]

Great episode, Kallie! Thank you so much.

[@martoneduard]

Finally an answer to my never ending question!

[@NexuJin]

I love to watch PBS Eons before sleeping. The narration is calming to listen to with interesting knowledge.

[@billallen2543]

Great episode. In my days as a Ag-Biotech researcher I was always amazed that polyploidy even existed. In animals, to my knowledge, it is unheard of as a normal condition (please correct me if I'm wrong. I'd love to know of a polyploid animal). In most cases the duplication of even one chromosome in an animal is devastating and often lethal. There are many human pathologies that result from the duplication of a relatively small portion of a single chromosome. As a classically trained zoologist who took up plant study because I needed a job, I found plants to be absolutely amazing. Hope to see more on plant evolution in the future! BTW, my crop specialty was corn, always was in awe of the wheat geneticists.

[@mariusstrand5220]

It is definitely rarer for animals to be polyploid than plants. Still, we know of several paleopolyploidization events in animals. It is more or less consensus that two rounds of whole genome duplication (WGD) occurred in the ancestor or all vertebrates (jawed ones at least). You can look up the '2R hypothesis'. From the top of my head, I can also mention that teleosts (96% of all fish) had a third round of WGD, and salmonids as well as carps each had a fourth round on top of that. I know fishes best, but beyond that, there are many examples in everything from amphibians to insects.

[@brendali5888]

So grateful for this video. More plant adaptation videos please.

[@Mesoblunt]

One of my favorite channels on YT

[@Seat1AJoe]

This show is terrific!

[@akumaking1]

“Life, uh, finds a way”.

[@TragoudistrosMPH]

🧬🧬 - we agree

[@t1sk1jukka]

Nice vid. We def need more vids of paleobotany. Though I’m more fascinated with fungi than plants and craving more fungi content on YT lol

[@suchendelokidottir5673]

This video helped me to resolve an issue with the world building in my fantasy novel I'm working on. I love when science solves a problem for me.

[@AuthenticDarren]

Plants are a most important form of life on Earth. And they don't need other forms of life to survive (for the mostpart) like animals do. They're definitely worth looking at far more. They're clearly survivors. I'd like to hear some more about plants.

[@villager736]

Cyanobacteria are superior

[@stefanostokatlidis4861]

Most plants need fungi to survive on land, and many of them today need animals too.

[@villager736]

@@stefanostokatlidis4861 True, but without cyanobacteria we would not have any oxygenic photosynthetic life, (plants, seaweeds, and algae), meaning life would still be stuck huddling around hydrothermal vents. Not to mention the fact that they generated the oxygen to make multicellular life seen possible in the first place.

[@AuthenticDarren]

@@villager736 Imagine then, another world where an intelligent form of life nourished itself in the same way as what we call extremophiles or cyanobacteria do. It would certainly cut down on life support costs for their space flights.

[@villager736]

@@AuthenticDarren Actually in a weird kind of way, we are actually extremophiles. Extremophiles that could tolerate oxygen far better then other forms of life.

[@samanthazeiger1553]

The alliteration in this script is 👌👌👌

[@patrickmccurry1563]

It is interesting to imagine how different of a plant environment the non-avian dinosaurs lived among.

[@astick5249]

For one grass wasn't widespread. Grass is like how we view mammals after the extinction of the non avian dinosaurs: completely taking the place of their forbearers and becoming widespread everywhere

[@chheinrich8486]

No emviroment we have today would looks like somehing a dinosaurs would have seen at least not completely

[@brad9189]

@@astick5249 I always wonder, before grasses, what plants occupied an environment like the Great Plains? There must have been habitats like this, with similar temperatures and rainfall. What plants grew there, and what animals ate them?

[@astick5249]

@@brad9189 I think a big reason many grasslands were around were simply because they are the only ones able to survive being so heavily eaten, basically their very predators helping them remain widespread, otherwise i think it was ferns and stuff that covered the ground, grass is one of a kind.

[@aengor]

@@astick5249 it’s not just that grass wasn’t widespread; for most, if not all, of the dinosaur times grass did not exist at all.

[@Snittyguy]

This is my favourite format of your videos.

[@gann2001]

7:44 Oh yep "recent" i remember it just like it was yesterday

[@guilhermebueno7282]

the pun at the end is always a challenge, but necessary for complete knowledge

[@TheDanEdwards]

Polyploidy is very common in plants even today. Many of the ornamentals we enjoy are recent polyploids.

[@corkinsme09]

I study amphibians so can't speak for plants, but in amphibians and fish polyploidy is found everywhere. In many organisms they are far enough away form the event that the chromosomes have fused. However, it is hard to find an organisms that does not have some chromosomal duplication. Mammals are weird in that they largely don't have a large genome duplication in their recent evolutionary past.

[@placidpond]

Cavendish banana is triploid

[@noelanderson969]

Even on City streets, they THRIVE!!

[@KimberlyGreen]

I wonder if polyploid plants would, someday, be useful for terraforming activities on other celestial bodies 🤔

[@starcrib]

I absolutely believe that to be so. You're instinctively right. 🟧♾️🟧

[@UniDocs_Mahapushpa_Cyavana]

Or *just for* agriculture. 🌱🌱🪴🪴

[@starcrib]

@Mahapushpa Cyavana indeed- ! and perhaps already has. 🌱🤔 🌾

[@joey2765]

Why do you look young and old at the same time

[@patreekotime4578]

@@joey2765 double genome, obviously.

[@annasfischer]

I would like to second the call from more plant content, and possibly even suggest a topic, because I would like to hear about the evolution of grasses (and also the eco systems they create!). Great video as always!

[@chrisp7641]

Is there a way to do a "what if" episode? Basically what would have happened if that meteorite hit the deepest part of the ocean? Like our current Mariana trench.

[@jasN86]

I've always looked at plants learning to evolve, and the already well established mushroom kingdom, and can't help but ponder about a possible connection

[@Alice_Walker]

I loved this video! So cool!!

[@NumbuhONE]

You're my favorite host! Wish you could do all the videos lol

[@incyray9709]

Wonderful video! I had always wondered how plants survived the cretaceous extinction, AND why strawberries and other plants have SO MANY CHROMOSOMES, and you just answered both questions! fascinating that they are so related!

[@lizzykayOT7]

Very cool episode, as fellow descendants of cataclysmic events, it's interesting to see how different species adapted.

[@proximacentaur1654]

Super interesting. More on plant genomics please!

[@moukidelmar]

This is really interesting, though I would like a follow-up video on how gymnosperms survived and, particularly, how living fossils like Ginkgos, Horsetails, Treeferns, Cycads, and so on pulled through

[@gailaltschwager7377]

Thank you!

[@SakuraAsranArt]

"Watcha doing?" "Nothing much, just doubling my DNA"

[@M0rmagil]

A very legit question, and one that is key to knowing what animals survived the K-Pg extinction.

[@mikaljan]

one of my favorite channels

[@jso6790]

This is so cool and fascinating, especially since the plants the group studied are those that humans have genetically modified through selective breeding, as well. It makes one wonder if the success humans had in breeding corn, for example, into the size it is today was related to the existence of those additional genes.

[@rJaune]

Wow, seeing the affected genes match to the environmental conditions at the time is fascinating!

[@bjarkeziegler7295]

Loved this episode 😊

[@emilylcasanovaphd]

Genes retained after WGD are often developmental genes, which are usually more dosage sensitive, so even losing them (despite being a homolog) can still be detrimental. So, it's not always immediately about "advantage" but "avoiding disadvantage."

[@jeffreycarman2185]

How interesting! Thanks for the video!

[@monniemo813]

More plant evolution please ❤

[@invisiblejaguar1]

That's a beautiful picture of those plants growing out of that alamosaurus skull.

[@avitalzehava5747]

Thank y'all for the wonderful content as always ❤

[@FloozieOne]

Plants are awesome and we never give them the attention and respect they deserve. After all, without them Earth would still be a barren lifeless world. Could you do another episode on which plants survived vs. ones that went extinct and what current plants are descendants of those survivors?

[@mellissadalby1402]

Very cool episode!

[@alexallen9640]

Interesting and fitting video for today 🙂👍🌿

[@SirDarthDragon]

I+d liked more explanation of tangential procecees: - why is polyloidery normaly a disadvantage? how does shade avoidance work? I usually have more problems following your paleobotanist videos. still love ya all

[@bjdefilippo447]

Fascinating! it's a smart strategy that makes you wonder about how the trigger functions.

[@thefisherking78]

Such terrifying imagery. That whole era is scary to imagine.

[@rcarter6541]

Absolutely fascinating! Are there any animals that also show this kind gene duplication from that time?

[@objetivista686]

There are 40 humans found that are chimeras too. Considered very rare for us. Search on google. There are some interesting cases.

[@bigpurplepops]

There are several, the best example off my head would be goldfish; which is why you can go from a 6lb coi to a bulb-eyed floaty spec.

[@trekpac2]

Polyploidy even shows up in our own bodies, where the heart and smooth call walls of vessels are tetraploidies.

[@stonefish1318]

More plant evolution please! 😃 🌵🌾🌲 These 3 would be maybe interesting 🤔

[@nitzneymann3977]

Earth's bio-history is an absolute beauty.

[@olivemd]

It’s nice when the comments are as interesting as theses are. Thanks everyone.

[@Howboutno1]

BABE, WAKE UP, PBS EONS POSTED

[@a787fxr]

I really liked this one. Thanks. 💯

[@johnwalters1341]

A very interesting episode. It leaves one big question unanswered, though: Why is polyploidy almost universally fatal in animals?

[@pencilpauli9442]

-Holmes, what kind of citrus tree is this? -A lemon tree, my dear Watson.

[@grokeffer6226]

Fascinating stuff. 🌱🌿🍃

[@RocLobo358]

You said "ancestor of potatoes" and now I'm thinking of possible delicious extinct vegetables

[@Stikkelsbær]

Yay. Nice to see a plant episode.

[@Rebel7284]

Any thoughts about why it's so common in plants and yet so uncommon in animals if it can offer such important advantages?

[@hopsiepike]

Animal development is more sensitive to gene dosage, that is, the relative amounts of different alleles if the same gene. Polyploidy messes with these ratios.

[@paulwallis7586]

Reminds me of the "junk DNA" thing; Why anyone would assume DNA has no use is pretty hard to understand.

[@NexuJin]

The way I see it is part of DNA are like main program data, where as the "junk DNA" are more just data, like assets or extra sub-routines. I just watched Picard S3E9.

[@paulwallis7586]

@@NexuJin Well, if you're prepared to duplicate a genome, that DNA seems to be useful, doesn't it?

[@helmutzollner5496]

Amazing!

[@SiqueScarface]

I like how the Common Dandelion (Taraxacum sect. Ruderalia; Taraxacum officinale) uses its polyploidy. In an average biotop, there are diploid, triploid and tetraploid specimen side by side. Diploid specimen are able to cross-pollinate other diploid plants, and their offspring is tetraploid. Diploid plants can also pollinate tetraploid plants, and their offspring is triploid. While tetraploids can only cross-pollinate with diploids, triploid plants are infertile, but can create offspring by cloning. But the cloning process is not very exact, and chromosomes get lost all the time. Thus, slowly the clones get more and more diploid, until they are real (or nearly real) diploids again. Then they can pollinate other diploids and tetraploids, and the next round starts.

[@CL-go2ji]

Wow. Thanks, that´s more interesting than the video was!

[@1TakoyakiStore]

I had surmised that there was a "rapid evolution mode" in plants. This was because animals when under times of stress have more mutations and you can see that in the form of a higher rate of cancer. But having duble DNA assist with this by doubling your mutation chances hadn't occurred to me but makes sense in hindsight. I daresay plant evolution is actually more interesting than animal evolution because plants have higher chances of horizontal gene transfer so they will get more new building blocks to work with which adds to the fun.

[@The_CGA]

Interesting new camera angle the wide from (a little bit above) I think y’all got a Camera B for green screen time and it’s cool!

[@christmassnow3465]

More about evolution: How did the earliest plants evolve from producing spores to flowering and producing seeds?

[@vanishingfolklore]

What a concept

[@Haydy5040]

Honestly you don't really even need the darkness so much for extinctions and extirpations at the K-Pg (plus we need more evidence of it). If you knock down diverse forests (from overpressure would do) you won't exactly get it growing back the same way as before since some plants might have an advantage they normally do not have. Funny thing is that in the Fort Union Formation there is a plant that suddenly appears just a bit above the boundary called Paranymphaea crassifolia which might be in the family polygonaceae which is known for it's aggressive weeds which might support the idea it was competition rather than just death over a short period of time. My own work in the Fort Union and Hell Creek is relevant here too and I'll eventually have some of that out here soon.

[@placidpond]

Japanese knotweed we’re talking about you!

[@PrettyBluePenguin]

More plant evolution please!

[@TJF588]

niche > niche Y' can't argue that!

[@sturner973]

Nobody: Hey asteroid what did you do to all of the plants? Asteroid: Oh sorry I was smoking trees 😅