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the pacific ocean is by far the largest body of water on the planet what this size means is that nearly every single one of the earth's continents has a coastline along its perimeter the only one left out being africa and by extension comes into contact with six of the seven biogeographic realms the neotropic the new arctic the pale arctic indus malaya australasia oh yeah and antarctica again with the only realms left out being the afrotropic if you're already confused about what
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all these terms mean don't worry i've already made a whole other video explaining this all so go watch it and come back here if you need to anyway with only the afrotropic left out this makes the pacific arena a true melting pot where nearly all of the earth's genetics can come together and build wholly unique plant and animal communities on the many islands scattered across this ocean all of which differ from one another but together form a patchwork of interrelated
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ecosystems a so-called eighth biogeographic realm the only problem is that while the pacific ocean certainly has loads of islands just teeming with life very few of them are actually big enough to support complex ecosystems beyond a few palm trees and seabirds this limitation in turn makes it hard to find an example where the full magnitude of the diversity at hand is on display in the environment in truth there may really only be one place across the whole of
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the pacific that's both far enough from any mainland and actually big enough to have developed its own full-fledged biota and that would be hawaii here we'll find the perfect biogeographical case study where its isolation tropical climate and extended natural history add up to what can only be described as the most fascinating evolutionary laboratory on the planet but also a lesson on how vulnerable much of the earth's most unique environments can be so today let's take a closer look at all the
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various aspects that make this place truly unlike anywhere else on earth
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[Music] now before we can get into the biology of hawaii we need to talk about its geography and the only real way to do that is to first talk about its geology of course it's no secret that these islands are all volcanic in nature but what makes them unlike most other volcanoes which typically occur in close proximity to fault lines giving them a distribution pattern that looks like this is that the hawaiian islands break this trend sitting smack dab in the
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middle of an oceanic plate nowhere even remotely near a tectonic boundary situated like this the only way for volcanism to actually poke through the surface here is if it comes from what's called a hot spot the result of strange and frankly poorly understood pressures coming from deeper within the earth's mantle while we might like to pretend we understand these phenomena the truth is we still know very little about the earth's core and what influences the
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magma beneath our feet leaving the cause behind this hawaiian hot spot a mystery to this day but okay let me speculate for a minute you see a while back i made a video on the surface of mars and i used well actually i used that map right there and taking only a quick look at it we can see this huge crater right here the helles crater and then on the exact opposite side of the planet we'll find the massive volcanic plane known as tharsis again occurring without any sort
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of tectonic boundary present to support such volcanism or we can look at our gaia crater a slightly smaller impact zone which sits directly opposite the slightly smaller volcanic province of elysium the idea here is simple asteroid impacts created these craters and either by weakening the crust or by sending a plume of magma shooting through the planet's core the energy of this collision event was transferred to the exact opposite side of the planet in the form of a lasting volcanic surge
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taking this concept and now applying it to the earth we can look at the chicksylub crater in mexico created by the very same impact that wiped out the dinosaurs and then going to its antipode lands us in the indian ocean at the head of a long igneous rock formation known as the 90 east ridge a linear volcanic province created as the hot spot beneath it stayed in place while the tectonic plate above dragged over it doing the same with hawaii we'll find its antipode
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falls somewhere in southern africa what's that are there any significant impact craters in south africa you ask why yes as it turns out there is in fact it's here that we'll find the vredefort crater literally the biggest and oldest impact crater we've ever found on the earth's surface now while you're not going to find this theory in any academic journals or publications not yet anyway i just find it suspicious that the world's largest impact crater sits directly opposite from the world's
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largest volcanic hot spot it just seems like they must be related and if so this means two things first the creation of the hawaiian islands is entirely the result of a cosmic coincidence a gift from the stars you could say but also considering the vretta fort crater is over 2 billion years old if it really is the source of this hot spot then it's likely been active for roughly the same amount of time making this probably the oldest site of continuous volcanism on
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the planet it means that at least some form of the hawaiian islands have existed on earth for nearly half of its entire history this has all been to say that even the volcanism that produced these islands is unique and whatever the cause of this hotspot may be the result of it was the creation of a chain of rather large islands nearly 4 000 kilometers away from the nearest continental lands like all volcanic islands when these first emerged from the ocean they had
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absolutely no pre-established forms of life they were utterly barren and so in order to amass a collection of plants and animals every single species had to be imported here from a mainland source but this geographic isolation sort of had a counterintuitive effect on the one hand being this far from any mainland made it difficult for both plants and animals to disperse here but i've said it before and i'll say it again life finds a way and so the species that did
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eventually manage to make their way here could have come from six of these seven biogeographic realms or in other words hawaii's isolation is also what brought it into contact with the entire rest of the world to really see what i mean we can take a look at studies like this one that dove into the origins of the island's many plant species doing this we'll find that despite sitting closest to north america the biggest source of hawaii's flora actually turns out to be
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indo-malaya accounting for over 21 of these species here i mean to be fair north america isn't all that far behind supplying over 19 percent of endemic plant species but considering the nearest part of the indo-malayan realm sits more than 8 000 kilometers away or over twice the distance the islands are from north america this really goes to show how hawaii's positioning opens it up to receiving species from everywhere in the pacific of course this still leaves us or at
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least me wondering why specifically indo-malayan species have been the most successful at colonizing these islands naturally there's no clear and straightforward answer to this so i'm gonna have to speculate again and the first thing i thought of was to look at the prevailing ocean currents doing this we'll see hawaii sits basically at the center of the northern pacific current to the west the current moves north potentially picking up seeds dropped by plants off the asian coast and
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delivering them straight to hawaii whereas the currents to the east of the islands moves south potentially diverting any seeds coming off the north american coast down and away in this manner the north pacific gyre acts almost like a conveyor belt carrying both indomalayan and pale arctic species directly to these islands and helps to explain why after north america east asia is the third biggest contributor to the hawaiian gene pool at 17 looking south however we'll find the
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equatorial counter current and past that the south pacific gyre which together make ocean dispersal from either of these southern continents much more difficult explaining why the neotropic and australasian realms are the least represented in the islands of flora with only 12 and 9 respectively of course ocean currents aren't the only things that disperse seeds birds do that too plus hawaii's tropical climate might also just make it easier for other tropical species to colonize it and
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overall there are a lot more factors that could go into this that i just don't have the time to talk about right now but okay if you do the math 21 from indomalaya 19 from the new arctic 17 from the paley arctic 12 from the neotropic and nine from australasia adds up to only 78 percent of hawaiian flora being accounted for so what about the remaining 22 percent well this is where things get tricky you see an additional 10 is marked as having a wide spread origin meaning they likely came from
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other islands in the pacific after all given that most of these islands are closer to one another than to any mainland it only makes sense that these would be the most immediate donors but even still this leaves the origin of around 12 percent of the hawaiian gene pool entirely unknown though of course there are a few theories like many people pointed out on my video on the seven realms some of these plants could have been donated by antarctica back when it still hosted plant life some 30
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million years ago or even from some of the realms reluct forests clinging to the bottom of south america and new zealand but to be honest i just don't know about this hypothesis i mean 30 million years is a long time and the circumpolar current around antarctica sure would have made it difficult for seeds to escape the southern ocean and then there's the fact that even if these hawaiian species did come from the ancient antarctic considering most of this continent's
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fossils lay buried beneath miles of ice and rock we likely wouldn't even be able to tell but if that leaves you a little unsatisfied don't worry there is another theory the best way to understand this one however is to actually look ahead of the islands where just a few miles off the coast of the big island will find the luihi seamount the newest volcano in the entire chain in another hundred thousand years or so luihi will emerge as the newest hawaiian island like all
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those that preceded it for a time this new island will sit as a barren rock utterly devoid of life but almost immediately it'll begin to receive inputs from all around the pacific arena of course when talking about oceanic seed dispersal distance is key and so the most immediate source of both plant and animal life will naturally be the other hawaiian islands assuming the same has been true for all of the islands that came before it this appears to suggest a lineage of purely hawaiian
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origin passed down over millennia from sinking island to rising island in perpetuity this would mean the hawaiian islands have been seeding their own life here possibly for as long as this hot spot has been active giving it more than enough time to develop species unattributable to any other lands on earth and might help provide an explanation for at least some of the otherwise unexplainable 12 percent of the island's plant species but again any fossil evidence that give
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validity to this hypothesis sits hundreds or even thousands of feet deep atop these seamounts and unless we investigate further we may never get an answer to this either way what we can see is that hawaii is home to a highly diverse plant community a crossroads of sorts serving as a collection of life from all corners of the earth in turn this unique assemblage of flora means that any animal that ever made its way here no matter where it originally came from would find an unfamiliar
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environment and would need to adapt in order to successfully inhabit these islands thus the prismatic nature of hawaii's plant life serves doubly as a driving force for evolution among its animal population producing an equally diverse and unique collection of native fauna of course being over 4 000 kilometers away from any mainland means the only animals really capable of getting here were birds with the only native land mammal being you guessed it a back the hawaiian
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horror bat to be specific which yeah looks about as crazy as you'd expect now while it might seem boring to have an animal community that consists almost entirely out of birds i'd argue that from an evolutionary standpoint this makes things more interesting you see speaking in general terms here on the mainland most birds serve roughly the same function being mostly small herbivores relying on seeds or bugs and trying to be anything different often means getting out competed by bigger and
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more robust animals like mammals however in an island environment where all these same niches still exist but aren't filled this gives what birds do make it here the opportunity to evolve into new forms they never could have sustained in a continental arena but okay before we get into it by now i bet some of you are wondering sure hawaii's cool and all but like why is any of this important for us to know after all i don't like spending this much of my time
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on a project if there's not some greater lesson behind it and it was only after making a video on the extinct birds of eastern north america that i was convinced there is something to be learned by looking at all these islands you see while learning about the extinction of the ivory-billed woodpecker the labrador duck the heath hen the carolina parakeet and the passenger pigeon still did convey the environmental devastation brought on by colonialism at the end of the day that's
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still only five birds to have gone extinct across the whole eastern u.s a surprisingly low number if you ask me especially considering how densely populated this part of the continent is the opposite however can be said about hawaii while the birds that called the eastern u.s home were still vulnerable to environmental degradation and excessive hunting by virtue of being mainland birds the presence of land predators fierce competition from all different sorts of animals and
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interaction with diseases made them all fairly robust species lending them a greater survival rate even after people started to arrive from across the atlantic the birds of hawaii on the other hand all exhibited characteristic island tameness where because they knew no form of four-legged predators were only used to competing against other birds and never encountered the diseases brewed up on the mainland were far more susceptible to the changes brought to their environment through colonization
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altogether leading these islands to lose many many more of their bird species so much so that i had to buy a book oh just to make sense out of it all well that and i like all the pretty pictures right here on the first page of the introduction we'll find this graph that might help convey just how much of a toll extinction has taken here on these islands put next to places that have also experienced colonization over the past few hundred years we can see all of them
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even the mascarene islands and new zealand pale in comparison to the loss of species suffered by hawaii in total 77 known species have been lost across these islands far more than anywhere else on earth or in other words just 0.003 percent of the earth's land area is responsible for over 15 percent of the world's lost birds this is what has earned these islands the title of the extinction capital of the world a name i can assure you you don't want to have what all this means is that in
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prehistoric times the geography of hawaii allowed it to become absolutely brimming with diverse forms of biology so much of that has been eradicated over the past thousand years or so that the only way to really see understand and appreciate what made this environment so amazing is to learn more about the birds that once existed here than the ones that still do now normally i don't like just listing things out it doesn't add much to a narrative and it just gets pretty boring
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pretty fast but it's honestly hard to convey the sheer number and variety of extinct birds any other way so just this once let me list all these out all 77 of them and then afterwards we can take a more in-depth look i'm out of breath more in-depth look at some of these okay trust me this will be fun because i'll have to pronounce all these really really hawaiian names with zero practice and you all get to make fun of me in the comments so let's go the giant hawaiian goose that one's easy
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the greater hawaiian goose the maui nui moanalo the oahu moanalo the stumbling moan halo the kawaii turtle-jawed goose the kawaii moldak the lesser hawaiian petrol the molokai flightless ibis the maui flightless ibis the hawaiian eagle the hawaiian harrier ziegler's crake molokai craig kepler's crate ralph's crake severn's creek the kawaii stilt owl the maui stilt owl the oahu stilt owl the the molokai still dowel the deep build crow the robust crow the narrow build
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kiowaya kiawea the nero build kiawea the mah the maka makawehi finch the makawehi finch the maui nui finch the giant scimitar build nuku the huppo build akihalawa the hupo build akihaloa the kiwi shovel build finch the polo layer the pololi the polo polo layer the pololi shovel build finch the straight build keeper the sickle build gaper the maui nui gaper the scissor build koa finch the oahu koa finch the wahi gross speak the king kongro speak the mauka grosspeak pilas
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palila pila's palilla cone build finch ridge build finch the kawaii palm creeper the laissan rail the hawaiian rail the kawaii oh oh the oahu o o the hawaii o o and molokai's o the kyoea the laissan miller bird the amaui the amaui the lanai aloma o the al the the lanai alum the lanai olaman [Music]
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that's a skit from may the kakawahi
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[Music]
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[Music] the oahu akihaloa the mauinui akialoa the lesser akihaloa the kawaii nukupuku the oahu nukapuku the the maui nukapuku the oahu akippa the maoia kappa the greater koa finch the lesser koa finch the kona gross speak the oh the mamo the black mammal the laissan honey creeper
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po uli poorly
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see i wasn't joking when i said there was a lot but hopefully at the very least now you have some idea as to the great diversity of birds that once lived here and okay i can already feel you all getting riled up against colonialism and trust me you're right to be but what makes hawaii such a special case in this instance is that it was actually colonized twice in recent history that's why here in the index of this book we'll see the list of birds split in two
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extinctions mostly before 1778 and then on the next page historical extinctions or ones that have been well documented in science literature the first of these waves came around a thousand years ago when the earliest polynesian explorers and settlers discovered and began to colonize these islands yep that's right it's not just europeans who colonized and decimated parts of the world that's more of a universal human trait apparently while the polynesians who first arrived on these shores
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definitely would have immediately contributed to environmental degradation by you know chopping down trees to build houses clearing forests to set up farms and hunting the local wildlife for food and feathers the most impactful aspect of their colonization was actually what they brought with them namely the dogs pigs chickens and rats that were taken either as livestock or as stowaways once here some of each of these naturally escaped and went on to establish feral populations that come to
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depend on the resources of the island aka the birds for their survival as well and suddenly these island dwellers who'd let down all their physical guards like the ability to fly behavioral guards like making nests up in trees and immune guards found themselves to be easy victims to the harsh reality that they'd grown vulnerable in this isolated island environment the first of these birds brought up in this book was the giant hawaiian goose now if you've been watching my channel
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lately you'll probably be familiar with the concept that often times when small animals like birds migrate from a mainland to an island the plentiful food and lack of predators tends to allow them to evolve into bigger and bigger forms a phenomenon known as island gigantism which as we can see here the giant hawaiian goose clearly exemplifies a descendant of the common canadian goose this was actually a relatively new member of the hawaiian fauna when the polynesians arrived having only spent
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around 500 000 years in isolation here this explains why it still appeared so similar to its relatives but also serves as a good showcase of just how fast evolution can take place considering that even over this short period the giant hawaiian goose had already become flightless allowing it to grow bigger and heavier than the canadian goose which has to stay more compact and lightweight in order to be able to fly but okay if we want to see birds that spent far more time on these islands to
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the point where they've actually developed adaptations to them then we can skip ahead a bit to the moanallo a clear sign that these were present across hawaii for much longer is that there wasn't one but actually four different species of moanalu each one specific to a different island you had the turtle jawed moanallo of kawaii the oahu moanallo of you guessed it oahu the small build moanalo of maui and the biggest of them all not coincidentally occurring on the biggest island the maui
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nui momonolu of yeah mauinui and if you're familiar with the hawaiian islands what i just said will strike you as wrong because well one the biggest hawaiian island is clearly the island of hawaii go figure and two there is no island in the chain even called maui nui and to that i'd say you're right there is no island called maui nui anymore you see in my last video i talked about earth's lost islands and we learned how just a few thousand years ago sea levels
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were up to 120 meters lower than they are now thanks to massive faraway ice sheets storing huge quantities of water on land with sea levels this drastically reduced far more of the underlying sea mount supporting these islands was exposed connecting maui molokai lanai and kahu olawe into the single island of maui nui or greater maui here the small build moanala was forced to keep entirely to the highlands of maui by the larger maui nui moanalu which being the biggest animal in the
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whole ecosystem dominated all the lowland forests while all four of these were about the same size as the giant hawaiian goose you could argue they're all better examples of island gigantism considering they evolved not from something that's already pretty big like a goose but rather from a much smaller dabbling duck compared to their closest living relative the pacific black duck we can see these moa nalo all went through a far greater growth spurt on these islands than the hawaiian goose
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experienced compared to its ancestor another indicator of just how long these giant ducks had to adapt to these islands can be found upon a closer examination of their beaks like this we can see they all developed a serrated edge almost like teeth which made them better for gnawing at plants well that is except for the turtle judd moanallo who was clearly just looking for attention while their purpose was likely entirely for gathering food they also had the unintended side effect of making
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them look really mean and angry all the time which i just think is funny because they probably did bully many of the island's smaller birds we can even see the giant hawaiian goose had started to evolve in this way not only serving as a good example of convergent evolution but also as an indicator that they were all eating foods normal geese and ducks typically would not eat this shows that all these birds were actively evolving in order to take advantage of open niches in their
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environment and by the time of their extinction occupied a role similar to what deer occupy on the mainland while that might not sound impressive deer are actually often the dominant herbivores wherever they roam and would have placed the moa nalo at the top of the island's pecking order of course while the environment certainly helped shape these birds so big was their impact that they too shaped their environment and a funny manifestation of this can be found by
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looking at the plants they most often ate like cyanea platyphilla over time these plants developed thorns covering their bodies and even their leaves a trait rarely seen in island foliage to defend themselves against being eaten by the moanalu because these birds went extinct less than a thousand years ago a very short period of time in evolutionary terms these plants continue to grow thorns even today despite their main predators being gone serving as a living memory of
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the time when giant birds still roamed these islands comparing hawaii's biggest birds against the nene the sole surviving native goose we can see it's definitely the smallest of the bunch and does little to convey the true scale birds had once attained here unfortunately while these birds might have been the biggest and baddest of the hawaiian islands pre-contact as soon as humans and their animals arrived they found their loss of flight and bigger slower bodies made them easy
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targets for any hungry feral dogs and in almost no time at all these giant geese and ducks had well gone the way of the dodo i guess you could say of course it wasn't just the big birds of hawaii that were driven to extinction after the first wave of human migration and in fact according to this book 42 of these 77 or more than half of the species and likely a lot more that we simply haven't found any fossils of yet had already been driven extinct before europeans ever reached these shores
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including many of the island's most adapted residents while i definitely can't talk about them all i would at the very least like to keep exploring the effects of island syndrome on hawaii so far all the birds we've looked at have been herbivores and as such the island environment had a similar effect on them allowing them to grow into giants compared to their ancestors but as we should all know by now the exact opposite can happen too if an animal's mainland strategy was to grow
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larger to either overpower prey or prevent itself from becoming prey its journey to an island could result in its shrinking over time a phenomenon known as island dwarfism in my last video i featured an example of this where the huge mammoths of north america evolved into a species of pygmy mammoth when isolated on the channel islands while no animals the size of mammoths ever made it to hawaii large mainland birds like eagles hawks and harriers did the only one of these to actually have been
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present on the islands long enough to have specifically adapted to them was the wood harrier a hawk-like bird that on the mainland preferred to hunt small mammals and reptiles however when the ancestor of the wood harrier found its way to hawaii it came upon a land completely lacking in its normal prey and so in order to survive had to switch over to hunting the many birds the islands had to offer this switch from feasting on the meaty bodies of mammals to lightweight birds
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meant the wood harrier could no longer support its great size and over time shrank into the smallest member of the harrier family unfortunately despite having maintained the ability to fly the safe island environment allowed the wood harriers behaviors to change as well as it started breeding and nesting on the ground instead of in trees because you know it's less work meaning once animals like rats and pigs were introduced their eggs were easily poached and once again
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were driven extinct by these invasive mainlanders all in all what i hope these examples of island gigantism and dwarfism help reveal is just how actively evolving much of the hawaiian fauna was a clear signifier that this environment was unlike anything the mainland had to offer of course there were plenty of other birds driven to extinction by the first polynesian settlers as well like mole ducks ibises a whole collection of stilt owls and so so many crates all
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exhibiting similar adaptations to their island home all equally vulnerable to newcomers meaning that by 1770 when the british captain cook became the first european to set eyes on these islands the animal community had already been drastically altered from its natural state that being said by this point most of the islands were still forested with many parts left completely untouched or in other words there was still more left to destroy and over the course of the
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next few hundred years not only would a new wave of immigration bring with it more deforestation for establishing sugar and pineapple plantations more introduced animals like cats goats sheep mongooses even wallabies and more advanced technologies that would accelerate the settling of these islands but they'd also bring with them an unintended passenger the deadliest creature this planet has ever known that would almost single-handedly begin a second wave of extinctions across these islands
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the mosquito yup that's right before the 1800s the hawaiian islands were completely mosquito-free a true testament to just how profoundly isolated they really are and as a result every animal living here gradually lost any sort of resistance or immunity to mosquito-borne diseases their ancestors might have had this all changed in 1826 however as whaling ships began to use these islands as a place to stop over and restock dumping their bilgewater as they waited and
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unknowingly introduced the insect for the very first time from here the wet tropical climate allowed the invasive mosquitoes to reproduce wildly and almost immediately picked up the diseases carried by the invasive chickens and began spreading them among the weak immune systems of the local wildlife and this is the major difference between the two waves of extinction brought to hawaii the first let's call it the polynesian wave most affected those species that had taken a
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special advantage of their island environment to adapt into some pretty interesting if ultimately non-competitive directions whereas the second or american wave reached any and all species mosquitoes could sink their teeth or proboscis into or in other words every single one of them making this a far more generalized extinction event claiming victims that may otherwise have been able to tolerate the rest of the changes humans brought to the islands in total 35 additional bird
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species have gone extinct since the arrival of american colonists or about the same number the mascarene islands lost in their entirety while i again can't look at every single one of these there are two groups of birds that i think are worth taking a closer look at the first are the oos a genus containing four known species the kawaii o.o the oahu o o the molokai o o and most sought after of them all the hawaii though there have also been some sub-fossil remains found on maui suggesting the
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possible existence of a maui ooh as well although we technically have no way of knowing what this mount o.o might have looked like if their cousins from the other islands are any clue i'm pretty sure it would have been a mid-sized black bird with some interesting yellow plumage just like the rest of them which is important because it was these yellow feathers that in turn earned the oos a special role in hawaiian culture you see the exceeding commonality of these birds
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in pre-american times meant enough of their feathers could be harvested to put together elegant robes capes hats and staffs absolutely covered in these soft yellow feathers turning them into the ultimate status symbol of hawaiian society only to be worn by nobility this by extension resulted in these feathers becoming highly valuable almost like a currency and thus managed to support an entire economy of catching and plucking these birds despite their value os remained fairly
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common birds before americans arrived thanks to the techniques used by the kia manu or bird catchers to capture and harvest their feathers which left the birds relatively unharmed and allowed them to be released once their feathers were taken however when americans arrived you just know they brought their guns with them selling them to natives and teaching them how to use them it took the native hawaiians about five seconds to realize simply shooting down the oos was far easier and faster than
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catching them by hand and pretty soon the acquiring of 0 feathers went from a methodical capture and release to a mass killing where over a thousand birds could be caught on a single hunting trip even still oos managed to maintain decent populations here until the arrival of mosquitoes that is and by extension avian malaria and suddenly they were all gone all four species and consequently their entire genus wiped off the face of the earth for good the point i'm trying to make here is
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that even with guns and a huge economic incentive to hunt them not even this was enough to fully eradicate the oo and had it not been for mosquitoes they might still be around today which i hope serves as a clear lesson on just how all encompassing of a threat these bugs pose i mean they literally did something all the money and guns in the world couldn't moving on the second group of birds i'd like to talk about are the hawaiian honeycreepers the story with these is
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basically the same as with the oos and the real reason i wanted to bring these up is because they can teach us another symptom of island syndrome that i haven't ever actually talked about before called adaptive radiation you see while they're stories of extinction might be similar the story of the honey creeper's evolution differs wildly from that of the o-o on the one hand each oo filled essentially the same niche as one another just on different islands this
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can be illustrated by comparing their beaks every bird's tool for acquiring food which we can see all look just about the same meaning they all fed on similar things when the common ancestor of the honeycreepers arrived in hawaii on the other hand they found a place where a multitude of niches remained open and so from a typical finch-like beak meant for picking up mid-sized seeds honeycreepers developed bulky gross beaks to pick up and open much bigger seeds examples of
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this include the king congress peak and the kona gross speak long and narrow hummingbird style beaks were developed to drink nectar from flowers as displayed by the many different akihaloa and nukapuku of the islands fat parrot-like beaks designed to break into fruits and typified by the o-oo small sharp warbler beaks for picking up insects off the ground which may have been the most common niche to spec into so i'm not going to give any specific example for this one unique hooked beaks
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to scrape bark off trees to find insect larvae developed only by the q and one the akihapola ao even specialized into a robust woodpecker style beak the only one of its kind across all of the islands that it uses to dig into trees to find embedded insects which lucky for us might be the only honey creeper i've mentioned so far that actually survives into the modern day amazing as it seems all of these different beak forms evolved from a single standard model again serving as a clear sign of just
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how much evolutionary pressure animals faced when they arrived here and okay if by now you're thinking ha this all sounds a little familiar that's probably because it was this very same evolutionary quirk that charles darwin first noted amongst the finches of the galapagos islands which had all undergone a similar if somewhat less extensive process that ultimately led darwin to come up with the idea of natural selection and by extension the theory of evolution itself
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although darwin never made it to hawaii if he had well first he would have absolutely loved it and second would have found much the same cases he had observed in the galapagos only to a far greater extent and probably would have used the honeycreepers as his primary case study rather than the galapagos finches but okay one thing that always happens whenever i make a biogeography video is i always end up focusing more on the animals than on plants sorry i just find
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them more interesting but the title of the video isn't the amazing zero geography of hawaii it's the amazing biogeography of hawaii and so if you really want to get a full overview of this place we gotta look into the amazing phytogeography of hawaii as well the reason i find this worth talking about is because like i said earlier being volcanic in origin every time a new island in the chain peaks above the ocean they begin with effectively zero life this means whatever plants arrive here
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first will find not only some niches open they'll find literally every niche open leading to the earliest plants to wash up on these shores to undergo a mind-blowing degree of adaptive radiation more so than any animal ever could since there are of course more of these than i could ever cover in a single video we're again going to have to focus in on just a single plant group the ones i found most compelling were what's called the hawaiian silver swords though
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to fully understand them we need to get familiar with their mainland ancestor nestled within the sierra nevada mountains of southern california if you look hard enough you may be able to find the rare carl kistia flower a member of the astor or sunflower family approximately 5 million years ago somehow likely by bird seeds of this rather distinctive flower made a trip to the california coast and from there all the way to the hawaiian islands for reference kawaii the oldest emergent
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island in the chain is only 5.1 million years old which means this colonization event actually pre-dates all of the other current islands while the carl kistia likely arrived to a young kauai already host to whatever types of plants had been passed down by the islands that preceded it at the very least there were still enough open niches for it to establish itself here from this point on the sunflower would witness new islands regularly sprout up from the ocean floor first niihau 4.9
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million years ago then oahu 3 million years ago molokai two million years ago maui lanai and kahoolawe some one million years ago all the way to hawaii just 500 000 years ago each time beginning a whole new sequence of radiation unique to its location but altogether related collectively forming what's called the silver sword alliance while of course many of these retained of their small flowering forms some like debashio herbstabate grew larger and more woody becoming a shrub in the
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process others like d arborio took this route even further growing taller with thick bark on their outsides to become full-fledged trees naturally wherever there are trees the ecological niche for vines also exists and so other members of the silver swords like d latifolia branched out into what are called lyannas that climb up and hang off trees of course other members of this plant family took the literal opposite approach too like here on mount waialeale
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standing as the second tallest mountain on the island of kauai waiale alay reaches high enough to force the moisture to condense out of the air passing over it producing huge amounts of rainfall in this one isolated spot creating an exceedingly wet environment at its summit that can only be described as a bog or swamp here the soil is so continuously saturated with water that many plants actually find it impossible to survive here not the silver swords though instead they branched into devashio
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waialealea a cushion-like plant that can sprawl out across a wide area while keeping mere inches off the ground overall the silver sword alliance serves as probably the best example of adaptive radiation there is having started as a fairly modest flower and evolving to fill virtually every niche available across these islands and i hope you think these things are as cool as i do because i'm not done talking about them yet you see another aspect of the hawaiian islands that
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makes them just so darn fascinating is that on top of their isolation on top of their diverse gene pool and well literally on top of their lush tropical climate these are also some of the only islands in the pacific that are mountainous enough to harbor alpine environments at their summits or in other words not only are hawaii's flora and fauna diverse but so is its very landscape meaning that if you started at the base of just one island you can move from an arid climate to a tropical one
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into a temperate zone and end up in near polar conditions all within a very short distance of each other creating an incredibly varied patchwork of drastically different environments where both plants and animals fight to occupy as many niches as possible this is perhaps most noticeable at summits like mauna kea's where the harsh alpine environment has prevented virtually all species from penetrating in from the tropical rainforests below that is except for these silver swords
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which if you'll remember got their start in the mountainous regions of california and i can't help but feel this gave them some sort of an edge as not one but two silver swords have moved into the alpine zone first in the highlands of mount hale aquila on maui where we'll find yep the haleakala silver sword and around the summit of mauna kea where you guessed it the mauna kea silver sword grows together these strange flowering plants stand as the only species present
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within the islands capable of making the jump to an alpine climate while simultaneously serving as the best example of why they're called silver swords in the first place while thankfully few of these plants have gone extinct you know being impervious to mosquitoes and all many still teetered dangerously close the mauna kea silver sword for example fell down to a total number of just 41 plants in 2003 mostly as a result of goats let loose to roam the island and if it weren't for the
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efforts of countless people working hard to breed and reintroduce these peculiar flowers they'd likely be gone by now which brings me to the last page of this book that i wanted to talk about if we flip all the way to the back
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all the way to the back we'll find the environmental nonprofit organizations dedicated to helping the native birds of hawaii if you've watched this far you clearly must be interested in hawaii and despite what this video might have made you think these islands are still home to some truly mesmerizing plants and animals like these so if you'd like to help preserve and protect them feel free to pause the video and go to any one of these organizations to learn more about how you can help
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overall i think the reason i felt it necessary to make what will honestly end up being like an hour-long video can be summed up in just a matter of words a unique geology produced a land with a unique geography allowing it to amass a unique collection of biology that once there all evolved together into a unique ecology which if you didn't know is kind of what this whole channel is about that's what makes the biogeography of hawaii so amazing and why i think it's
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worth learning about because while both the polynesian explorers who first discovered hawaii and even the americans that later come to colonize it knew little about the lasting impacts their actions would have on these islands today we know better and so if we want to prevent the loss of hawaii's remaining 23 endemic birds as well as the rest of its flora and fauna we're gonna need people who know who care and who are willing to learn from the past to preserve our world's natural
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treasures for the future hey everyone thanks for watching if you enjoyed this and want to see me take more up close looks at fascinating islands give this video a like and let me know what specific islands you'd want me to take a look at next in the comments i hope at least some of you appreciate these longer videos because they never really seem to do well which means i really need to rely on my patrons if i want to keep making more of these so please if you stayed around for
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this long and would like to see more videos like this in the future consider helping to support me and the channel by checking out my patreon besides that well at the time of writing and recording this i'm super close to reaching a million subscribers but i have a feeling that by the time i finish making this video i will have already gotten there so don't bother subscribing i don't care anymore i'm just kidding of course subscribe to see new videos right when they come out
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and i'll be back soon with another one thanks
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