Obligatory disclaimer: real life sucks, but everybody knows
it… What is next?
Let us talk about zebras instead. As everyone knows it, they
are the wild, striped, (black and white), horses of Africa… only not.
Yes, zebras are kin to horses and donkeys, (as well as to
the rhinos and the tapirs), and they look like horses covered in stripes. In
reality, however, the genetic evidence shows that zebras and horses, (both wild
and domestic) are the most distant relatives out of the three equine groups;
the zebras and the donkeys, (again, both wild and domestic) are much closely
related to each other than they are to the horses, no matter how similar the
three groups of perissodactyl mammals may look to each other.
…’Perissodactyl’ means ‘odd-toed’ – horses, zebras and
donkeys have a single toe on each foot; the much more massive and robust rhinos
and tapirs have three toes on their front legs, and four on their hind. The
artiodactyls – even-toed ungulates – have two or four toes on each foot, an
even number instead. Next?
…The two groups of herbivores are not close relatives to
each other; the artiodactyls, in particular, these days are recognized as the
sister group of cetaceans – whales, dolphins and porpoises. The latter names
are informal themselves, and are gradually being taken out of circulation or
are being clarified and reworked in various official sources themselves.
None of that involves the perissodactyls – they are their
own group, (ok, a biological order), separate from the cetacean—artiodactyl team.
In the past, they had their own aquatic representatives… actually, the
Malaysian tapir and the Asian species of rhinos still spend a lot of time in
the water; moreso than the South American tapirs, let alone the African rhinos,
which are the most terrestrial of the bunch, as well as the most biggest.
Horses, donkeys and zebras, however, shun wet places unless
they need to drink, and actually can flourish in places where their artiodactyl
counterparts do not do so well – for example, the dry steppes of Central Asia. Camels,
of which we have talked before, of course, flourish in deserts, but camels
themselves are an old group of ungulates, and their own heyday has passed – these
days, there are three species of ‘true’ camels, and four species of ‘camelids’,
but we’ve talked about camelids & camels before, and right now, we’re
talking about zebras instead.
There are three species of zebra – Grevy’s zebra, plains
zebra, and mountain zebra. They differ from each other in stripe patterns and
in general body shapes, and they also live slightly different places from each
other. The quagga, which is a perissodactyl ungulate that had a striped neck
and head, but not the body, was a subspecies of the plains’ zebra instead.
Why the quagga is mentioned? Because just like the Thylacine
and Steller’s sea cow, this animal died out in the ‘historical’ times; there
are photos, and maybe skins and bones of the animal, but no live quaggas, not
anymore. There are rumors of scientists being able to reverse-engineer extinct
animals, such as the giant ground sloth, the woolly mammoth, and the passenger
pigeon, but the initial rush of this excitement quietly fades away, and we are
left with nothing, not even the status quo.
As for reverse engineering the quagga using breeding and
hybridization… that is trickier. The modern zebras can hybridize with each
other and have fertile offspring, but the zebra-horse and zebra-donkey hybrids do
not do so well, on the other hand…
Well, this is it for now. See you all soon!
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