Rise of the Moa

The Moa of New Zealand were among the weirdest birds to ever live, and their history is full of evolutionary wonder, interspecies conflict, tragedy and scientific hope. In this Stuff to Blow Your Mind two-parter, Robert and Joe discuss the rise and fall of the great Moa.

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Episode Transcript

Speaker 1 (00:03):
Welcome to stuct to Blow Your Mind production of My
Heart Radio. Hey are you welcome to Stuff to Blow
Your Mind? My name is Robert Lamb and I'm Joe McCormick.
And to uh introduce today's episode, I thought maybe we
should begin by reading a poem. Robert or you game,

(00:23):
I'm game for a little little poetry. In fact, it's
not just poetry, it's moetry. I did not make that
joke in my head yet, but maybe because I'm not
as perverse as you. This is by the New Zealand
poet Alan kernw This was originally published in nineteen and
it's called The Skeleton of the Great Moa in Canterbury Museum,

(00:44):
christ Church. The Skeleton of the Moa, on iron crutches,
broods over no great waste. Deprivate swamp was where this
tree grew feathers. Once that hatches, it's dusty clutch and
guards them from the damp. Interesting failure to adapt on
islands taller but not more fallen than I, who come

(01:05):
bone to his bone. Peculiarly New Zealand's the eyes of
children flicker around this tomb under the skylights. Wonder at
the huge egg found in a thousand pieces piece together,
but with less patients than the bones that dug in
time deep shelter against the ocean weather. Not I some

(01:25):
child born in a marvelous year will learn the trick
of standing upright here. You can find that poem, by
the way, in the nineteen seventy nine anthology and Anthology
of twentieth century New Zealand Poetry. And Yeah, I really
love the cadence of that poem, and also I feel
like it effectively captures the weird beauty of these reassembled

(01:47):
skeleton remains one sees of the mighty moa. You know,
we just did Marianne Moore in the paper Nautilus. This
is another poem like that. I love a good poem
that genuinely ponders biology like this deals with the evolutionary
reputation of the moa, the flightless birds of New Zealand,
uh and and the idea of learning the trick of
standing upright. Yeah. Now, this is gonna be a fun

(02:09):
couple of episodes. I'm really excited about these episodes. I
think the moa is one of the things that's really
keeping me going right now. You're getting to research read
about the moa and envision the moa. Uh No, no
matter what where I don't know where you are out there,
if you're listening to this, where you are in your
previous understanding of of the moa and other flightless birds.

(02:30):
But this is a this is a wonderful and weird
story that has as a number of number of connections
to things we've talked about in the past, but but
also some new angles. We're gonna be talking about evolution,
We're gonna be talking about first contact between man and beast.
It's a it's gonna be a fun ride. And there's
no better place to start a fun ride than in

(02:51):
New Zealand, the land of avian decadence, that's right, And
and the place where the mammal is truly debased. That's
right because you I knowbviously, the rise of mammals is
one of evolutions most celebrated victory stories, right because in
part because we are, of course mammals ourselves, and there's
perhaps a sense of of the gods and the primordial

(03:11):
titans when we consider the age of the dinosaurs that
came before us in our own mammalian age that we
have you know, ascended uh in now, well, yeah, I mean,
there's very much a case of when you look at
the Cretaceous paleogy and extinction event that caused the demise
of the non avian dinosaurs. Uh, it's quite clear that
their loss was our gain, yes, but it was wasn't

(03:32):
only our gain. It was also the gain of of birds.
And we often neglect the just the exceptional dominance of
birds for theirs is the the the legacy of the
of the dinosaur, and then they remain highly successful and
widespread to this day. They remain masters of the air,
frequent masters of the water, and sometimes masters of the
land as well. Now, why would birds be the masters

(03:54):
of the land, Like they've got the air that seems
so much better than the land, why even bother with
the land? Well, of course that the obvious answer there
is that is that to be a master of the
of the air requires a great deal of energy, and
if you don't have to fly around, you quickly find
reasons not to Evolutionarily speaking, of course, Well, so if

(04:15):
we're talking about mammals and avian dinosaurs or birds, why
exactly was it that the loss of the dinosaurs was
the gain of these other clades? Well, because suddenly you
have all of these uh, these niches in the in
the in the in the in the environment that open up. Uh.
That's suddenly a bird can can occupy, or various creatures

(04:35):
have the ability to occupy mammals included. But this is
where we see the emergence of a number of these
different flightless birds. This is where we see the emergence
of the terror birds and the demon ducks. Uh. And
we'll get into some more examples of flightless birds as
we go. Uh. But yeah, to be sure, we still
have some amazing flightless land birds with us today, and

(04:56):
some of them are are quite enormous. The largest, of course,
is the ostrich. There are two species remaining. There was
a third, the Asian ostrich, that went extinct roughly six
thousand years ago. Yeah. The two extant species are the
common ostrich and the Somali ostrich, and they're both native
to Africa. Yeah. And I sometimes I feel like we
sometimes overlook how cool ostriches are. I find that it's zoos.

(05:19):
They you know, the one thing, it's a zoo habitat,
and and you know it's it's you're seeing an ostrich
in a fenced in area. But then sometimes the Ostrich
is in there with a giraffe, which seems particularly unfair
because the giraffe, of course, is the is the tallest
um extant mammal that we have. And it feels kind
of like a dirty trick to showcase the world's to

(05:40):
the world's tallest extant bird with the tallest mammal which
towers over it. Right, It's like I'm trying to show
off my muscles, but then you put me next to
a gorilla. But but we have some other wonderful examples
of flightless birds, uh elsewhere. For instance, we have EMUs,
which are very fascinating. You get a chance to just
look at an emu, just watching emu as it goes

(06:02):
about its business. It's it's remarkable. The cassowary is one
of my favorites mine too. There's a cassowary here at
the Atlanta Zoo, Cecil Cecil the cast wary, who we
we've talked on the show before with with a friend
Jason Ward here in town about Cecil the cassowary, who
remember Jason telling us that it's dung is very like

(06:22):
fragrant and kind of smells of fruit, even though it
is the I mean not to demonize animals, but when
you get up close to it, it is a horrifying beast.
Like it's beautiful. Its colors are beautiful. It has the
blue and the red and the black feathers. It's a
gorgeous animal. But also if you look at its foot,
it's foot looks like a puppet from a monster movie.

(06:44):
You know it is. It is just a killing thing.
It's got these claws and this scaly, scabby skin. Uh
that's a tongue twister. But yeah, look at a cassowary
up close sometime if you just want to be terrified
and audit nature. And yeah, they they can. They can
prove quite deadly if you know, the human comes into

(07:06):
close contact with them and there they begin engaging in
the defensive behavior. Yeah, don't try to look at their
feet up close if there is not a like barrier
between you. Yeah. Of course, we have other flightless birds
who consider one of the more amazing ones. Of course,
it's the key we of New Zealand um the nocturnal
ground bird. All of these birds are what we call rattites,

(07:28):
a diverse group of flightless birds that were widespread across
the scattered fragments of the supercontinent don Dwana UH and
the and their dominance is waned over time, certainly with
the rise of Homo sapiens. We still have all these
various examples that still remain today. Yeah, and you find
you find large flightless birds, well actually large and small

(07:49):
flightless birds everywhere from New Zealand to South America. Yeah,
you know, and that's without even getting into the the
the obvious example of just other flightless birds. There's also
the penguin, of course. But well, this raises the question
why do we have flightless birds all over the place
like this? Well? Uh. In the nineteen nineties there was
a wonderfully titled theory MOA's arc which would assume that

(08:14):
all of these ratites descended from a common ancestor. So,
in other words, that the idea here is that a
a flighted ancestor became flightless on god Dwana, and then
as the supercontinent split, this one flightless ancestor UH diverged
into all these different flightless species. Okay, so you get
one instance of these birds descending from an ancestor and

(08:36):
becoming flightless, and then the flightless one goes all over
the place, and then there's continental drift, the supercontinent splits up,
and the flightless descendants of that one ancestor all go
off into different places and evolve in different directions, and
they become everything from the Ostrich to the key We
to the moa. Right. But one of the issues with this, UH,

(08:58):
this idea is that this would mean we'd expect something
we'd expect, say in New Zealand, we'd expect the moa
and the kiwi to be closely related to each other.
We'd expect that any any of these ratites that live
close together would also be closely related, but subsequent DNA
studies have revealed that this was not the case. Instead

(09:18):
of MOA's ark, the model seems to be one of
numerous cases of flighted to flightless evolution around the world.
So again, convergent evolution. UH. This repeated instance of a
flighted bird evolving into a bird that doesn't fly, which
seems so strange of a of a choice for evolution
to make. I mean not to personify it too much,

(09:39):
but but what is the advantage there? I think we
alluded to this earlier. One of the main theories about
this is that it's an energy advantage. If a bird
doesn't need to fly, then it doesn't need to make
huge pectoral muscles capable flapping wings that can get it
into the air. And if it doesn't need to make
those big muscles, it spend that energy on something else,

(10:02):
or it can just survive on less food. Yeah, and uh,
and it can have just like a smaller it can
have less of a basal metabolic rate. And we we've
talked on the show pretty recently about birds having a
pretty high BMR. So so yeah, this is basically the
reason why we see the rise of these various flightless
birds and in you know, all corners of the world

(10:22):
really But then of course a number of them end
up falling away. And of course we'll get into the
details of of of the fall of the moa in
these episodes. Uh, in the case of the moa and
in the case of the elephant bird, it's it's the
encountering human beings that did the trick. Yes, once again,
human beings seem to be a sort of anomaly in

(10:44):
the fossil record in the evolutionary story. Once we enter
the picture, things tend to go haywire. But another question is,
coming back to what we were just talking about like
the energy considerations in losing flight. So it is clear
that you can save a lot of energy by not
being a flying bird if you don't need to fly.
But in what case would a bird not need to fly?

(11:05):
Shouldn't flying always help a bird to survive? Well, basically
it comes down to, like like we said earlier, the
death of the dinosaurs creating these these holes for it,
these niches for it in the environment. You need a
place where I mean to use a very simple even
tacki metaphor here for birds they need a place to land, uh,
in a place it's not already occupied by say a

(11:27):
highly successful dinosaur or highly highly successful mammal. And so
there there are corners of the world, uh, you know,
other shards of Gondwana where the the the idea of
a kingdom of the birds remained at least partially unchallenged
by mammalian usurpers. Like nothing came nothing was already there
to keep the bird from landing, and nothing came up

(11:50):
to U to erase it from the ecosystem. Um. For instance,
there's the island of Madagascar, which enjoyed something like eighty
eight million years of isolate Asian during which it fostered
various forms of lemur as well as the massive elephant
bird uh not only a rattite but often considered the
largest known rattite to ever walk the earth. But then

(12:14):
there's also far flung New Zealand, which enjoyed an amazing
degree of freedom as well from the mammalian revolution, well
until roughly umred c e with the arrival of human beings.
Now that's not to say they were completely free of
mammals that believe they're too extinct, primitive mammals known only

(12:35):
as the Saint Bathans mammal that are present in the
in the fossil record from the Miocene. Otherwise, the only
way for a mammal to get to New Zealand was
to fly there or to swim there. So you'd have
this huge island that's got birds on it, but does
not have any large mammalian predators. It doesn't have any lions,

(12:57):
it doesn't have any wolves, it doesn't have any foxes,
anything for a bird to need to fly and escape from.
So if you don't have a predator you have to
fly and escape from, why even keep making wings Exactly?
You just you land and you start filling those niches.
There's no buffalo there, no horses again, no wolves. And

(13:17):
then the as far as the other mammals, the ones
that have swam there. I mean, we're talking about seals,
sea lions, whales out in the waters around New Zealand.
And they they're they're they're not gonna invade the forest
anytime soon. Uh, they're doing just fine. And then other
than that, we have bats. Bats flew to New Zealand,

(13:38):
where we do see you do see an interest in
case where where the bats that come to New Zealand
end up spending more time on the ground than you
see elsewhere in the world, particular the New Zealand lesser
short tailed bat, which spends a lot of its time
foraging on the forest floor, crawling around, um, basically taking

(13:58):
on a far more terrestrial a role than bat's employee elsewhere. Again,
this would make sense as an evolutionary adaptation if there's
just not a lot of stuff to worry about on
the ground like there is everywhere else. Yeah, Like we
mentioned the kiwi earlier, Like the kiwi is an example
of a ground dwelling bird. Uh, you know, it goes
around at night, it eats things like worms, but there's nothing.

(14:21):
There's nothing like a mole. There there are no moles
to fill that niche in the environment. Uh, therefore the
kiwi is is taking that role on even though it
is a bird. Now you do see some cases where
reptiles or gastropods are also you know, filling in these
these niches in the environment in New Zealand. But for
the most part, the birds are the real stars here. Um,

(14:43):
we mentioned the kiwi and there are there are numerous
other examples of flightless birds in New Zealand. There's a
there are various extant species that we still find, such
as the South Island tacky heat and then there's also
a flightless bird known as the Weka. But the most
amazing examples are the nine now extinct species of moa,
including the giant moa that used to uh To to

(15:06):
exert their dominance over New Zealand. Well, maybe we should
take a break and then when we come back we
can talk about this giant bird. Thank alright, we're back.
So we just introduced the character of the moa. This,
I guess we alluded to a little bit earlier. But
this giant flightless bird that used to inhabit New Zealand.

(15:28):
That's right. Yeah, there were nine different nine different species
are known to exist. There's the upland moa, the little
bush moa, and I have to stress the little bush
moa was still one point three meters or four point
three ft tall, so it's still a sizeable bird. Wait
is it now? Is it the little bush moa or
the little bush moa? Uh? The little bush moa sometimes

(15:49):
just referred to as the bush moa. I'm just trying
to think. I mean, is it like a bush moa
that's little or is it being compared to a little
bush or something? Oh? I think it basically lived in
the bush bushma would have would have lived more in
the rainforest. So essentially the moa is so successful. You
have all you have like nine different varieties and different
parts of New Zealand. Uh, different sizes. By the two

(16:11):
largest were dinormous Robustus which means robust, strange bird, and
dinornous novels Olndia. So we're largely gonna be talking about
those two because they were the biggest. We're talking about
moa that reached the heights of three point six meters
or twelve feet tall. That's with the neck outstretched and

(16:31):
there with with estimated weights of two or five and
ten pounds. So these were these were sizeable critters. They
looked rather like an enormous emu. So if you've seen
an emu in in person, you have like a good
starting point for imagining them. Like a wide, kind of
shaggy feathery body on long uh you know, lethal looking

(16:56):
legs with these great claws at the end, and a
long snaking neck you know, almost like a like a
like an like an elephant's trunk, at least a too
comparatively small head, yes, and the skeletons. It's almost like
a comically small looking head compared to the gigantic nous
of its body. But so another one thing I would
wonder about, of course, is okay, well we know it's

(17:18):
probably flightless, but what does it do with its wings?
Does have a little a little like t rex arm
talons up there or what's happening with the wings? Well,
that's that's typically what you expect, right. Flightless birds typically
have at least vestigial wings, a little shrunken remnants of
their long neglected flying limbs. Uh. Sometimes, as with an ostrich,
there's still some sort of a use for these wings.

(17:40):
The ostrich uses it's it's so it's little wings there
to stabilize them when they run and to aid in
courtship displays, even though they're you know, they do not
produce flight at all. Right, Well, I mean you can see, uh,
some birds that are thought to be flightless actually do
kind of glide near to the ground. Some I'm like
chickens can use their wings to kind of glide around

(18:01):
near the ground. Right. But but even failing that, like,
sometimes there's some purpose, even if it's a display, right, U.
And even if there's not a purpose, you might expect
to find, as with other flight was birds, to find
some vestigial remain of that limb, you know, like little
bones or something. But the moa doesn't even have vestigial wings.
There are no little not like even like shrunken bones

(18:24):
that are left over. There is no trace of their
wings at all. They have simply been erased through their evolution.
That's creepy. It's yeah, it's amazing. It's it's it's one
of the very few known creatures to possess only two limbs.
The only other creatures that I could run across that
were in a similar situation at all are the Mexican

(18:45):
moble lizard and the Serenada salamanders. Both of these are
cases where creature has lost its hind legs and retains
it's its front limbs. But you won't find any mammals
that are like this. Even the hind legs of the
great whales remain in this stigital form um. No, you
find no other birds, no dinosaurs, just these nine species

(19:08):
of giant land birds. Even the t rex w it's
you know, famously small, um you know, four limbs. So
we've we've discussed the various theories for why they kept
even those those tiny limbs on the show before. But
even the t rex still has little little arms. The
moa has no arms, no, no wings at all. It's
just such a strange creature. The other day I was

(19:29):
imagining it as a kind of biological unicycle. Yeah, yeah,
it's it's so weird. It's it's like some of the
illustrations look oddly huggable, but it has no arms, it
has no wings, like there's nothing. I kept thinking like,
why does this, why does this amaze me so? And

(19:49):
I think part of it is that when we think
about animals so I've noticed when when children think about animals,
they often embody the animal, you know, they have to
like act like the animal, uh, you know, pandomiment and
so forth, which is a fascinating tendency. By the way,
why do they naturally do that? But I think even
if we're not like actually moving our bodies around, when
we look at animal, there's part of us that like

(20:11):
puts ourselves in its body, and we imagine our limbs
as its limbs. And this creature has has no uh,
nothing like arms at all. So if you're trying to
get this in your head, just you know, stop, if
you have a chance, look up some images of the moa,
of its skeletal remains, and also reconstructions of what it
would have looked like, and just focus on the fact

(20:33):
that it has no vestigial wings. It's just so wonderfully weird. Now.
I know you said it it looks huggable, and I
sort of agree, but I do want to stress if
they actually recreate these things and bring them back from extinction,
do not try to hug them. No, that's a very
bad idea. Right. Yeah, we discussed how potentially lethal the

(20:54):
castle areas and the same can be said of the
ostrich So I think without a doubt the moa could
do some areous damage. You are still around to kick you.
Oh and by the way, if you if you want
to look up some images of the moa or just
get additional information about them, I highly recommend checking out
New Zealand Birds Online, created by ornithologists Colin ms Kelly.

(21:15):
It's a great Uh, it's it's great. It's one of
the sources we use for these three episodes. Uh. And
you'll find you find it an in z birds online
dot org dot in z and if you go to
the search bar and you type in moa, you'll get
pictures of all nine varieties illustrations of all nine varieties
of moa. Now, one thing that's kind of interesting about
the moa is we often tend to think, okay, where

(21:37):
there are large land dwelling animals, they often tend to
be few in number. Right. But the but for a
long time, New Zealand was kind of the land of
the moa, right yeah, Yeah, The moa where New Zealand's
dominant land vertebrates and dominant herbivores. So they basically we
went around consuming twigs, leaves, flowers, seeds, and berries from

(22:00):
a wide variety of trees, shrubs, and vines. They also
ate um mushrooms, which we'll get into a little later. Uh.
They were able to process a highly fibrous diet due
in part to large gizzard stones and a tough beak.
So I met those gizzard stones were involved in some
great curses probably so excellent magical items. Um. But yeah,

(22:25):
so they're they're basically every again, nine different varieties, like
basically adapting over time to the different environments of New Zealand.
And Uh. They laid enormous eggs and are suspected to
have produced I think one or two per breeding season,
and the incubation period was likely longer than two months.
So big birds, big eggs, um more of a time

(22:47):
investment in a limited number of eggs, and the male
likely incubated the eggs, as this is what is seen
in extant ratites. I don't think I knew that. Now.
Just because it was the dominant land organism doesn't mean
it was completely unopposed, that it was off the predation hook,
because again, this is the world of birds, and and

(23:07):
when you think of birds, you probably think of a
number of different flesh eating varieties, and so the moa
too had to contend with a mighty avian predator, and
that predator is the largest eagle to ever live. Right,
So at this point, I want to briefly come to
one of our favorite subjects, which is monsters. Why are
there so many monster movies about giant spiders but not

(23:30):
about giant lions? Uh? Well, a lion is already large enough, right, Yeah, exactly.
So I've got a hypothesis here. I think humans, whether
through instinct or learning or combination of both, do a
lot of intuitive phylogenetic sorting of predatory threat imagery. So
the idea of a large cat that kills and eats

(23:51):
you is in fact terrifying, but it's not especially unusual
in the terms we've talked about on the show before,
in the terms of cognitive science of religion. It's not
even minimally counterintuitive. It's just sort of a fact of nature.
So it would be terrifying if you were really faced
with it. But it's also not a particularly arresting image
in the memory, and that it doesn't stand out. I mean,

(24:12):
I'm sure it would be a memory if it actually
happened to you, but probably not in terms of fictional storytelling.
Compared to something like a giant spider, A large man
eating spider is definitely counterintuitive. It's not something found in nature,
and because the image is unusual, it sticks in the
mind and captivates our fear. And I have to think
about this for a while. Like the idea of a

(24:33):
human being eaten by an invertebrate like an insect or
an arachnid, not only feels scary, it feels perverse. It
violates the natural order. In Biblical terms, I think this
is what would be called an abomination, and so I
think our brains do this kind of unconscious threat math
a lot. We sort potential threats from animals or organisms

(24:55):
more generally by morphology or body shape, which is a
simple way of sorting them along evolutionary relationships. Large carnivorous
mammal shapes are natural predators. They are genuinely threatening in reality,
but less captivating of the terrified imagination. I think the
same goes for large reptilian shapes like crocodiles or sharks

(25:15):
or whatever. But here's another phylogenetic or morphological branch of
potential threats. How about birds. I think we intuitively sort
birds into the non predator pile, right, Like we prey
on birds, they don't prey on us, right, Yeah, for
the most part. I mean now to come back to
the cassowary and the ostrich, Like, clearly these are both

(25:38):
potentially dangerous animals that they're encountered in the wild, but
they are you know, they're kind of exceptions from the rule.
They are a rather different rate of bird than the
the sort of bird that most of us are going
to encounter on a daily basis, right, And they wouldn't
be trying to hunt us. Like, if we encountered one,
you know, a cassowary in the wild and it was
being aggressive, that would probably be it. You know, from

(25:59):
its point of view, it's acting in defense. Right now,
if we were to travel in time back to the
age of the terror birds and the demon ducks, and
that would be a little it would be a different scenario. Yeah,
but I would say that that age might go a lot,
It might come a lot more recently into history than
we would think. Uh So, maybe this, this intuitive sorting
about birds is one of the main reasons movies that

(26:22):
use dinosaurs as monsters resist putting feathers on them, right,
even though many predatory dinosaurs probably had feathers, we associate
feathers with birds, and birds are generally not thought of
as scary, right, Yeah, when, for instance, when we think
of all the times featheries are used for comedic effect, right,
like a feather pillow feathers, uh, you know, stuck to

(26:43):
a person after you know, something sticky has has has
gotten on them, that sort of thing. Yeah, And so
there's that. But then on the other hand, and pretty
much in exactly the opposite direction of what I just said,
we want to think again about the counterintuitive thing. A
lot of times monsters are great because they violate these categories. Know,
no spider actually praise on us in the wild, but
we love the giant killer spider idea that sticks in

(27:05):
the memory. There are a lot of stories about it,
and there are stories of giant predatory birds that do
show up in monster mythology all around the world. There's
the rock, the cock a trice, the winged on zoo
from Sumerian and Babylonian myth like do you remember how
in Bandersnatch it says that the demon packs is the
thief of destiny. The humanoid bird monster on Zoo is

(27:29):
the original thief of destiny. Do you know about the story?
And so in this uh, there's this ancient Akkadian epic
where on Zoo the bird the humanoid bird monster, steals
something called the Tablet of Destiny from the King of
the Gods. And the Tablet of Destiny is kind of
like this great law book that's sort of a like
the permanent record of everybody. It's got like all of

(27:51):
their you know, the I don't know, all their lawbreaking
or whatever written down in it. And possessing this document,
this tablet gives you the power to rule the world.
And so when on Zoo the bird monster steals it,
he has to be destroyed I think by Marduke. Well
that's what Marduk's for rights, that's pretty much his job.
I mean, Marduke. It's funny Marduk is the hero of

(28:13):
the story, but in in my feeling, Marduke's also he's
often kind of the party pooper, Like there's a great
monster getting up to no good and then Marduke comes
in and just puts a lid on everything. Yeah, he's
the humanoid figure that that gets rid of the interesting characters.
He's like the assistant principle that comes in and stops
the party. Um. But so I think the bird as

(28:33):
man eater story. It does pass the minimally counterintuitive test
for mythological resilience. If a giant hawk could swoop down
from the sky and bite your head off, that image
that makes a good story that would stick in your memory. Um. So,
I'm not sure how exactly that goes in conflict with
the fact that, like people won't put feathers on dinosaurs
and movies because they're not scary enough. Maybe maybe these

(28:55):
things two things are just both true and in competition
with each other. Like the feathered monster has a cognitive
advantage because it's more counterintuitive stands out in memory, but
the scaly monster has a cognitive advantage because it's physical
features are more naturally prone to activate our threat responses.
I don't know what you think is going on there,
but as we we love to think about monsters, and

(29:16):
I think that that tension is interesting. Yeah, and and
again we're talking about the idea of monstrous birds here,
not just birds perceived as a threat, because certainly there
are people that are afraid of birds or a little
wigged out by birds when they're close to them. Certainly
Hitchcock's the birds managed to strike a nerve with people.
But yeah, the idea of a a bird being large

(29:37):
enough to do not just like pester you or two
uh or too certainly in a large number attack you,
but like a single handedly take you out and consume you,
to prey on you, to to hunt you as if
you were its dinner. Yeah. Uh. Now I want to
talk for a moment about a very important fossil in
physical anthropology, which is a fossil skull that is between

(29:58):
two and three million years old. I think last time
I saw the dating it was like two point eight
million years old. They thought it was unearthed from a
quarry in South Africa in nineteen four in a place
called Tongue. And it is the skull of a young
hominid now known to be from the extinct human relative
Australopithecus africanus. And note that this is a different species

(30:20):
from australi Epithecus afarensis, which is the species to which
the famous Lucy skeleton belonged. Uh So, this Africanus skull
is known as the Tongue child, and evidence indicates that
this hominid died when it was about three years old,
and we actually have a lot of evidence now indicating
exactly what happened when it died, how its death came about.

(30:42):
Just a warning. This is a kind of sad and
grizzly story, but also biologically fascinating. So the tongue child
skull has puncture marks in the bone at the bottom
of the eye sockets, and these puncture marks are similar
to the marks made on other man mammals like monkeys
when eagles attack them today. Also, the skull was found

(31:06):
in a soil bed along with eggshell fragments, as well
as the bones of many other small animals, including rodents, lizards,
juvenile antelopes, and baboons, and a lot of these other
bones also show damage that looks like it could have
been caused by the beaks and talents of a large eagle.

(31:27):
The South African paleontologist Lee Burger has argued that it
was an eagle that killed this child. He argued for
the eagle predation hypothesis. For example, in in a short
communication I was reading to the journal the American Journal
of Physical Anthropology in two thousands six, writing that quote
re examination of the tongue juvenile hominin specimen, the type

(31:49):
specimen of Australia Epithecus africanus reveals previously undescribed damage to
the orbital floors that is nearly identical to that scene
in the crania of monkeys preyed upon by crowned hawk Eagles.
And Burger argued that this evidence, along with the strange
collection of other animal bones at the side of the

(32:09):
tongue child's discovery quote, strongly supports the hypothesis that a
bird of prey was an accumulating agent at tongue and
that the tongue child itself was a victim of a
bird of prey. I think this is an example of
how scientific writing so often has a way of stating
things that is like facially abstract, bordering on euphemistic, but

(32:32):
so much so that it actually sounds more horrifying. So
this bird of prey millions of years ago was not
a bone collector but an accumulating agent. Well, that makes
it look it sounds like it was working for some dark,
other force. Right now, if this hypothesis about the town
child is correct, uh, and from what I read, I
think it probably is. Uh. We don't know for sure

(32:55):
exactly what kind of bird killed the child, but the
paper I was just quoting from raws attention to the
similarities between the marks on the fossil skull and the
wounds left by a modern bird of prey. It still
exists today, called the crowned hawk eagle or stefan Oidas coronatus,
also just known as the crowned eagle. This is a

(33:17):
truly frightening and magnificent bird, so it lives throughout central,
southern and eastern Africa, mostly inhabiting like mountains and forests.
Rainforest places with tall trees also sometimes found in the savannahs.
These eagles can weigh up to ten pounds or about
five kilograms, with a wingspan of up to six feet

(33:38):
or about a hundred and eighty centimeters. They're large, they're
not the largest eagle. The females are generally larger than
the males, and the crowned eagle gets its name from
a crest of feathers on the head. Sometimes it's got
feathers sticking straight up, but sometimes it looks just like
a bulging of the feathers towards the back of the
head and looks a little bit like Gary Oldman's weird
vampire bun head from the Francis Ford Coppola Dracula. It

(34:02):
does really Yeah, do do you see what I'm saying?
And plush? The spirit of of the two are closely
linked here. Yes, I imagine this eagle also loves the
children of the night because like Dracula, this bird is
an astonishingly strong hunter. They've been known to kill prey
more than four times their size. And I think this

(34:23):
is this is key too, because certainly, even in an
urban environment like in Atlanta, we see vultures and hawks
fairly common. Hawks especially, you see them around a lot
because there's a lot of a lot of creatures for
them to prey on. We went into the the urban
advantages of the hawk in our one of our previous episodes,
Oh Yeah. We talked with Jason Warred about the about

(34:43):
the peregrine falcon and it's urban hunting methods where it'll
sit up on top of a building and wait for
its prey birds to fly underneath and then it die
of bombs them from above. But generally you think about
a bird like this grabbing a bird of this nature,
grabbing something like man maybe a sad and maybe it
grabs a squirrel. Uh, maybe maybe it even gets a
small dog. But you don't think about them grabbing something

(35:06):
four times their size right now. If they grab something
four times their size, they're not going to be able
to carry it away. But they can totally kill this
thing and either eat it where it falls, or take
it apart and take pieces with them. So when attacking
large prey, the predatory strategy of the crowned eagle often involves.
It'll it'll involve swooping down from above and then using

(35:30):
their meaty legs and fearsome hind talents to break the
prey animals spine when they make contact. Uh. They hunt
a diverse range of prey, including monkeys, antelopes, and other
small mammals and lizards. Uh. And they, like I was saying,
two basically feasting strategies. Once they've got a prey animal dead,
if it's small enough, they'll try to carry it with

(35:51):
them up to a safe tree top to eat at
their leisure. If the prey is too large to carry,
they will either eat it where they have killed it,
or sometimes they'll they'll they'll tear you know, chunks of
it off. They'll tear off ahead or tear off an
arm or something and take it away with them, one
piece at a time. Another interesting fact about them, the
crowned hawk eagle sometimes uh. Well, so, they generally lay

(36:13):
one or two eggs per nest brood, and if there
are two eggs, when the eggs hatch, the larger of
the two chicks usually kills its sibling. The parents are
known to guard their newborn chicks very ferociously. You know,
they violently repel encroaching animals. And so you might have
a question, well, would these powerful hunters that can kill

(36:34):
animals much larger than themselves, would they be able to
attack humans today? Uh? Possibly, but if so, it is rare.
I don't wanna, you know, get you in the idea
that you should be afraid of or demonize these birds.
But there are a few accounts of crowned eagles attacking children.
The accounts are mostly older. It was kind of hard
for me to tell how much stock we should put

(36:55):
in them. But such a claim of crowned eagle attacks
on humans does not at all seemed to be unheard of,
and they do regularly attack monkeys, which of course are
shaped a lot like us, and small human children would
be within the size range of their prey. Remember, they
can attack prey more than four times their size, so
they can attack animals that are maybe like forty five pounds,

(37:16):
or again be in awe of their predatory strings. I
don't mean to demonize these animals, because I know their
habitats are threatened now and their numbers are declining, and
but in general, a smile child is likely to to
flip certain switches in a in a sizeable predator that
might normally not not switch on when they see a

(37:36):
fully grown human. Oh well, yeah, I don't know if
you ever looked up those videos on the internet of
small children against the glass and like lying enclosures at
a zoo. Oh, I mean, I've I've taken my son
when he was smaller. I remember taking him to uh
some sort of a zoo like uh place somewhere else
in Arizona. I think maybe it was Arizona even But

(38:00):
but when we were there, it's like there was a
one part. We're walking out there are these cages, and
they had some large predatory cats, and you can just
see them like there's a change in the way they
are viewing their surroundings. There's a change in their body language.
You can you can tell that they're you know, even
if they're not actively hunting your child, they're reacting to
it as if it is potential food. Yes, I mean

(38:21):
the same way that the human instinct is activated by
a small child. You know, most adult humans would see
a small child and want to say, is that child okay?
You know you want to take care of them delicious. Yes,
the looks very small, very weak, easy, easy kill. Not
to shame any of these predators, that's just that's just
the coating. That's the basic UH way of the tooth

(38:43):
and claw. They're right. So you've got these claims of
modern eagle attacks on on human children. But if these
claims are generally correct, even then it does appear to
be a kind of unusual thing to happen, you know,
something that just happens here. And there was there for
a predatory bird that would have had humans more firmly
within its prey buffet, but you know, even larger, even

(39:07):
more diverse in the kinds of prey it would seek out.
And that brings us back to New Zealand. UH in
the age of the Moa and the MOA's primary enemy.
It's it's primary predator, the has eagle. So the Maori
people of New Zealand have had legends of gigantic birds.

(39:28):
Apparently there are several different legends of gigantic birds that
have been linked somewhat too real bird species. The two
different legendary bird monsters that I was reading about from
the Maori where the ta Hokioi or the Pua Kai.
But there may be other legends that sort of fit
into this mix as well. And uh and in real quick,

(39:48):
I want to again reminder that the Maori came to
New Zealand less than a thousand years ago, so we're
talking um roughly. Eh. Well, we'll get more into into
the history of the Maori and they're they're coming to
New Zealand and their eventual interaction with other human beings
uh in our in our second episode. But just remind

(40:09):
everybody about the time frame we're talking here. So this
this giant bird monster of Maori legend. It's a huge
bird with black and white feathers. It's got a red
crest and yellow green coloring on the tips of its wings.
It was believed in some legends to have raised the
hawk to the heavens and was known in other some
legends as a man eater. It's not only a feature

(40:31):
of Maori oral tradition, but it's it's terrifying frame appears
in archaic rock carvings of the area, and many paleontologists
now believe that the this animal, the ta hokioi or
the Puakai, is not purely fictional mythical as a monster
like the on Zoo. It may be the cultural memory

(40:54):
of this real giant predatory bird of New Zealand, known
as the Hosts eagle or Harpagurnus mori, which again would
have been the predator that preyed on the moa because
again less than a thousand years ago when the Maori arrived,
when the archaic mallory arrived in New Zealand, they would
have encountered, uh the nine species of moa. They would

(41:16):
have encountered Hosts eagle in its predation of the moa.
Like all this was the world, this unique environment was
in full swing when they first arrived. Hosts eagle was
a beast. I think if we saw it we would
be in awe It could weigh up to fifteen kilograms,
which is about thirty three pounds. The female might have

(41:37):
had a wingspan of up to three meters or almost
ten feet. Like other birds of prey, often the female
was larger than the male. Remember that the most powerful
predatory bird in the world today not the largest, but
the most powerful hunter, the crowned eagle, weighs up to
only about ten pounds or about five kilograms. This is
like three times bigger, and with their size and hunting power,

(42:00):
hosts eagle could and did regularly take down moa as prey.
To think about how amazing this is given the size
of the moa. What were we saying about the size
of the moa earlier? Oh, we talked about ten to
twelve feet with their with their head stretched out. I
mean even the even the bush moa was like four
and a half feet tall, you know, like, yeah, the

(42:20):
little bushma. Yeah, I'm sure they were. They were really
at a loss here. So a predatory encounter might have
involved waiting at say a tree top near a water source,
and then waiting for a moa to come out and
take a drink, and the hosts eagle could then swoop
down at the moa at eighty kilometers per hour about
fifty miles per hour. And again, think of something that
weighs forty pounds hitting you at about fifty miles per hour.

(42:43):
Some forensic analysis of the bones of the hosts eagle,
I know there was some analysis done through cat scans
and things. Uh. This shows that the eagle's body was
by design able to absorb shocks from high impact speed.
Um So at the impact the predator comes in, talents
out and it has talents that could penetrate bone. So

(43:05):
after killing the moa or the other large prey bird,
the eagle could usually take its time eating the kill
in the spot because they were not large mammalian predators
to worry about coming along. Because this is New Zealand, Yeah, yeah,
I've I've also heard it. Heard it described that the
talents of Hassi eagle were about the size of a
tiger's clause. That's how big they were. Yes, So I

(43:25):
was reading an article in The Independent that interviewed Paul Scofield,
curator of vertebrate zoology at the Canterbury Museum. This was
in two thousand nine and Schofield is also the author
of one of the papers that was doing the forensic
analysis of the hostiagle skeleton. And also, by the way,
the Canterbury Museum is the same place where Alan Curnow

(43:46):
saw the Moa skeleton that he writes the poem about.
But so Schofield says, quote, it was certainly capable of
swooping down and taking a child. They had the ability
to not only strike with their talents, but to close
the talents and put them through quite solid objects such
as a pelvis. It was designed as a killing machine.

(44:06):
So think about So it comes in with the claws extended,
can hit you at high speed with amazing force and
then latch on with the claws to cut through flesh.
And this would of course leave you bleeding and all
of that. And Schofield said, has eagle wasn't just the
equivalent of a giant predatory bird, It was the equivalent
of a lion. Wow, Yeah, a lion of the air. Again,

(44:28):
it's just a it's like an order of magnitude beyond
any kind of flying predatory bird that we have we've
become accustomed to in our our world today. Yeah, I mean,
I guess I think like a like a griffin, you know,
like this this is a flying it's like a flying
big cat if a leopard could fly. So again the
Maori arrived, they encounter this world and uh, you know,

(44:51):
and we'll discuss the details of this later, but basically
the moment would last scarcely more than a century after
that they were they were rather swiftly a adicated by
human beings, and therefore hoss eagle. Since it depended on
the moa for food, it went away as well. But
there would have been time there, so there was. There was,
There was a period of time and Mallory history for

(45:12):
their for the archaic mallory and for the moa hunting mallory,
for for them to have their children picked off by
this terrifying bird, this terrifying predator of the sky. It's
hard to imagine, but I just did. Well. I mean,
they're terrifying predators of the land. Are bad enough when
they can come from above. I don't know what. That
just seems like that would that would entail a whole

(45:35):
reordering of the way you view, you know, danger and
safety in the world, because you generally think the sky
at least is safe. I don't need to look that way.
All right, We're gonna take a quick break, but we'll
be right back and for more discussions of the mighty moa. Alright,

(45:56):
we're back. So one question that comes up. We're in
man eationing this this clash between these enormous moa and
this enormous eagle clash of the giant birds, and so
I was wondering, well, how does how would a giant
moa defend itself? And like what kind of fight could
it put up? So we already mentioned how if we
look to extent to ratites, we looked to the Austrians,

(46:18):
we looked at the Castle Wary, we see excellent examples
of just how ferocious a kick from one of these
creatures would be. But then you start image. So if
you're imagining, say, say an unarmed human uh coming up
and trying to start uh sort of fight with say
an Austria's or Castlewary or perhaps a moa, that's not
a good idea. You can imagine how that's gonna go

(46:39):
kick wise, um, you know, or or any type of
land predator trying to mess with one of these these creatures.
But if something is coming from above like it does seem,
and I couldn't find a lot of sources on this
about like what the MOA's defensive capabilities would have would
have been But if it certainly have it had trouble
kicking that high. What could it do if something was

(47:01):
attacking its back? You know, it could it could peck
at it. It could use its beak certainly, Um maybe,
and this is just me guessing. I'm thinking maybe it
could whip it with its neck a little bit. That is,
that is the strategy we see with giraffes. You know,
there's there's footage of giraffes fighting each other with using
them next as these broad whips, and certainly the cat.

(47:21):
Certainly the MOA's neck was was long and tough, but
I don't know if it could actually have used it effectively,
certainly against host eagle, which again is this this lion
of the sky attacking it with enormous talents and perhaps
making pretty short work of it if it got the drop. Well, yeah,
if you're coming out a large bird like the moa

(47:42):
from below, I mean obviously that that's not the place
you want to be. But what does it do on
its back? I mean, it seems like the perfect place
to pray on it, and you can make wounds on
the back of a large bird. Like this, that is
it's exposed and you know, if you can get the
talents in there and get out, even if you don't
break its back when you first hit it. Uh, probably
just like what bleeds to death, it's it's there and

(48:03):
drowns in its own blood. Yeah. So it seems like
a case where the moa was just particularly vulnerable to
hass Siegel. But at the same time, it means hoss
Eagle was particularly dependent upon the moa like they were.
They were locked in this. In this you can say
eternal struggle. I guess you want to get be dramatic
about it, but really an eternal balance until until this

(48:26):
new force, this new terror, came to unbalance that that equation. Yeah.
Well it's um. I mean, it's weird to think about
because like when you see a predator chasing prey in nature,
I think naturally most of our sympathies are with the
prey animal, and that makes sense. Like you know, if
you were to see one person trying to hurt another person,
your sympathies are with the victim. But in in nature

(48:50):
you could think about it as a as a kind
of balanced thing because the predator is also trying it's
just trying to survive. It is fighting starvation every every
day in this same way that the prey animal is
fighting the predator that's trying to kill it. Right, And
again we we already mentioned We'll get into some of
the genetic data on this in the next episode. But
the MoMA was highly successful and it was spread all

(49:10):
over New Zealand, so you know, it was a situation
where it could support a dominant predator like this. Their
numbers were such that the predator was ultimately playing an
important role in supporting a healthy moa population. Yeah, totally.
I mean, one thing I've read is that the hostiegel
probably would have been very few in number, right, like

(49:32):
most apex predators are, right, you know, they tend to
be their needs to be many fewer of them than
there are of the prey animals or the or the
ecosystem can't sustain itself. Now, it's it's easy to grasp
only the extinction of the moa came hand in hand
with the extinction of of the great hass eagle, But
extinction impacts a wide variety of species, and when you

(49:54):
have such an established creature as the nine moa species,
you have a lot of organisms that come to depend
upon them. So you know, you're talking about bacteria, parasites,
fist scavengers, predators, but also whatever plants and fungi have
come to depend on their feeding habits to propagate. And
so I ran across an interesting study that got into

(50:16):
some of this. In two thousand eighteen, researchers from the
University of Adelaide's Australian Center for Ancient DNA or a
c a D published a study in the journal the
Proceedings of the National Academy of Sciences about the contents
of dried dung from four varieties of giant moa. Thank god,
we're getting into some copper lights. Yeah, I mean we can.

(50:37):
You can learn a lot from copper copper lights. You know,
they're highly useful and uncovering the especially in this case
the genetic records of diet pathogens and even the behavior
of the creatures in question. So the researchers here found
that the moa consumed a wide variety of mushrooms and
fung gui, including species that are critical for New Zealand's

(50:58):
beach for us, and they were they were very interested.
The researchers were very interested in exploring the prior but
unproven hypothesis that many New Zealand fungi with bright colored
fruiting bodies are adapted for dispersal by native ground dwelling birds.
Now this couldn't really be tested because all the moa
are extinct, But but this gave them a chance to

(51:21):
sort of to explore it a little bit, right, Okay,
So in general they found confirmation regarding diet in a
few moa species. So they found that the little bush moa,
for instance, which would have resided in the rainforest, fed
mostly on fibrous forest vegetation. Upland moa and giant moa
were widespread dietary generalist, with upland moa populating the higher altitudes,

(51:46):
so they would have eaten a wider variety of things.
But the mushroom contents of the moa dung uh certainly
contained plant symbiotic fungi that the wide ranging moa would
have spread as they ranged, grazed, and pooped. According to
lead author Alex Boast, then PhD student at Land Care Research, quote, worryingly,

(52:09):
introduced mammals which consume these mushrooms don't appear to produce
fertile spores. So this critical ecosystem function of the giant
birds has been lost, with serious implications for the long
term health of New Zealand's beach forest. So what does
that mean that? Um, the mushrooms passing through the digestive

(52:30):
system of the birds would have still been reproductively viable.
But going through mammal digestive systems, they're not. Right. The
mammals that have come in to fill that ecological niche
that was left by the by the now extinct moa
like there, they'll eat the same mushrooms. Perhaps they'll even
spread them, uh even you know, travel you know, to

(52:50):
decent distances. But the spores they leave behind are not viable.
They're not able to actually uh fulfill the role that
the moa fulfilled in spreading those spores. And again, those
the mushrooms uh have this crucial relationship with with the
trees of the beach forest. So um, this is again
I think it's just a it's a wonderful example of

(53:13):
of the cascading effects of extinction. They also found evidence
of parasites in those copper lights. They found a quote
surprising diversity of parasites, many completely new to science. Oh boy,
and these are these are largely parasites that would have
been exclusive to the Moa uh and or the Moa
species in question that just went extinct with their hosts.

(53:34):
And these included, for instance, various types of nematodes uh.
So you know again, you you you can't take a
species out of the out of the game without impacting
numerous other species as well. And it's certainly going to
be the case when you have such a firmly established
and dominant species as the Moa of New Zealand. I'm

(53:55):
mourned for the Moa. Yeah, it's hard not to, you know,
I mean, I do want to stress that that, and
we'll get more into the relationship between the Moa and
the Maori people in our next episode. But it is
crucial not to not to feel a special amount of
shame over over the Maori in this situation, because again,

(54:16):
any time human beings have come into contact with new ecosystems,
they have brought extinction with them. We change everywhere we go. Yeah,
and that's that is just that is the nature of
human beings. Um, you know, no, no matter where they go,
no matter what the time period. We did a previous
episode where we talked about Roman extinctions just brought on

(54:37):
by the spread of Roman civilization. Um, and we previously
mentioned the elephant bird of Madagascar, similar situation. Uh it was,
it was doing really well than humans came, and that
spelled its doom. Now, the story of that doom in
the case of the moa is something we're going to
get more into in our next episode. Though. You know,
I just thought of another thing from Madagascar. I believe

(54:59):
I was just reading earlier today that a an extinct
relative of the crowned eagle of Africa was the Madagascar
crowned eagle. But it's gone because when humans came to Madagascar,
they hunted its primary prey animal, the giant lemur, to extinction,
and then it had no prey anymore. There you go,
all right, So we just keep doing it, and we

(55:22):
just keep doing it, and yes, some some amazing creatures
have been lost along the way. But I tell you,
the moa. It I'm just really impressed with this animal.
I think it is my It is my my new
spirit animal for these trying times we live in. Uh
I will I will ease myself into the imagined arms
of the moa. It has no arms, It has no wings,

(55:43):
but there's something about its nature that I can I
can cuddle up with and uh and find comfort in.
You're gonna become the lower ax of the rat eye.
It's you're gonna go on a quest where you want
people to stop using the ostrich as the example animal
of like cowardice and ignorance. I'm gonna have to I
need to get out of the house and go look
at some rattites this uh, this weekend. There is there's

(56:05):
an email that lives fairly close to my house. Yeah,
what's its name? Big Glue? Biglue the email. I don't
think I may have to go feed Big Glue this weekend. Okay,
I don't think I know about Big Glue. Oh well,
I'll tell you about it when we go at the air.
You can find Big Lu for yourself alright. In the meantime,
go and check out other episodes of Stuff to Blow
your Mind. They're a bunch of them. You can find

(56:26):
them wherever you get your podcasts, and you can also
find us by going to special Blow your Mind dot
com that will shoot you over to the I heart
listing for this show wherever you get the show. Just
make sure you rate review and subscribe. Huge thanks as
always to our excellent audio producer Seth Nicholas Johnson. If
you would like to get in touch with us with
feedback on this episode or any other, to suggest a

(56:48):
topic for the future, or just to say hello, you
can email us at contact at stuff to Blow your
Mind dot com. Stuff to Blow Your Mind is production
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visit the i heart Radio app, Apple Podcasts, or wherever

(57:09):
you listen to your favorite shows.