Obligatory disclaimer: real life sucks. I have no idea when
it will end and we are stuck in the lockdown, and it is snowing again. What
next?
Let us switch from amphibians, such as newts, to ostriches.
Why? Because I have watched one of David Attenborough’s specials – ‘big birds
can’t fly’ and it is about ostriches and the other ratites, so let us begin!
First, there are actually two species of ostrich – the common ostrich with its’ subspecies,
and the Somali ostrich, which differs from the common ostrich in terms of
coloration. (A blue neck and head, primarily). It coexists with the common
ostrich, (with one of the subspecies, anyhow), but does not hybridize with them
– apparently, they are that different
genetically.
…This situation is not too unique to the ostriches – other birds,
physically very similar to each other, do not interbreed either, for example
the white and the black storks of Europe/Eurasia. Externally, they differ only
in plumage color, but nevertheless, no hybrids.
Back to the ostriches. They are ratites, aka the
paleognaths, aka a group of very specialized flightless birds that are only
distantly related to the rest of the birds, aka the neognaths. They are other
flightless birds in the modern world, but they live on islands where no land
predators are present, and they have keeled sternum bones as well. Penguins, in
particular, have fairly powerful wings and they can fly, only underwater, not
in air. And the ratites?
Out of this superorder of birds, ostriches are the most
basal slash ancient ones, followed by the rheas, (aka the South American
ostriches). These birds are the biggest existing ratites, and they got big
wings. They still cannot fly – too heavy, the anatomy is all wrong – but the
big wings serve to impress females, to shade chicks from the sun and so on.
Speaking of South American rheas, this continent also has
the tinamous. They are important, because while they belong to the ratites,
they actually can fly, just not very well, and are the local ecological
counterparts of pheasants and grouse from the rest of the world. (The
galloanseri birds are some of the more ancient birds, alongside the ratites,
but we will talk about them some other time). As such, they got added to the
ratites only recently, and even that with some caveats, I think – but more on
tinamous later.
Next, we got the cassowaries and the emu of Australia and
Papua New Guinea. They are more advanced than their African and South American counterparts
are, and have no wings. The emu is represented by a single species; the
cassowaries – by three, (the fourth had died out). The emu lives in the
savannah, just as the ostriches and the rheas do, while the cassowaries prefer
the jungle. Pause.
Here I take a breather from taxonomy, and point out that the
cassowaries are not like the extinct dinosaurs, raptor-like claws on their feet
or not. Raptors were carnivores; cassowaries are not – they feed of fruit and
other plant matter, and if possible, they avoid humans, who encroach on their
territory, cutting it down to clear land for their own needs; most
human-cassowary conflicts are human-initiated, sadly.
Finally, the living ratites also feature the kiwi birds,
which are the smallest ratites of them all. Also, unlike all the other ratites,
existing and extinct, rather than have long necks & legs and short bills,
they got short necks, shortish legs, and long bills, with which they prove
earth for their sustenance – various invertebrates. They are nocturnal, got an
attitude, (just like the rest of the ratites, actually), and number five
species – the most numerous modern ratite groups.
The rest of the ratites are extinct by now; of a particular
interest are the moas of New Zealand, (cousins to the South American tinamous),
and the elephant birds of Madagascar, (cousins to New Zealand’s kiwi birds). The
moas were the tallest of the ratites, the elephant birds – the heaviest. Both
of these ratite groups died out during the historical age – the moas from the
New Zealand Maoris, the elephant birds – from the natives of Madagascar and the
Europeans, possibly. Unlike their mainland cousins and the kiwis, they were
just too specialized and tasty to survive, it seemed. The moas, in particular,
had only their drumsticks slash legs eaten and the rest was given to the dogs –
literally. No wonder that the moas died out, as did the elephant birds, though
in the latter’s case it was more of a habitat destruction situation instead.
Anything else?
Sadly, no. The modern ratites are flourishing, more or less,
but many of them are in trouble, (remember the cassowaries’ issues with
humans?). ‘Big birds can’t fly’ has addressed that issue, though this film was
kind of a tangled mess, featuring bits and pieces of previous BBC/Attenborough
productions, but I’ve still enjoyed it. Beggars cannot be choosers – cough,
Comic-Con 2020 is cancelled because of COVID-19, cough.
Well, then, this is it for now. See you all soon!
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