Mules 2: Beasts of Burden

Mule: Getty Images

Say the word mules to some people and they'll think of the favoured shoe of sex-kittens, much loved by artists, fetishists, and fashionistas.  

However, for those philosophers of animality, such as myself, with a keen interest in the natural world, the word refers, of course, to heterotic donkey-horse hybrids that hugely impressed Darwin for - amongst other things - their intelligence, memory, and powers of muscular endurance.   

To be precise in the matter, a mule is the result of interspecies shenanigans between a male donkey (or jack) and a female horse (or mare); something easier to obtain than a hinny which is the offspring of a male horse (or stallion) and a female donkey (or jenny).

What's interesting is that the mule provides us with an example of what's known as hybrid vigour - i.e. a form of genetic enhancement. For they are reputed to be not only more robust and longer-lived than horses, but relatively less stubborn and more intelligent than donkeys. This shows that artificial selection and unnatural couplings can, in fact, sometimes produce superior offspring.   

Not that the more snobbish members of the horse-breeding community concede this; they still tend to look down on the mule as an inferior creature (if not genetically, then socially). That said, although long excluded from traditional horse shows, mules have now been accepted for competition at some of the most prestigious shows in the world. 

Sadly, whilst in the industrialised world mules, like horses, have largely been replaced by machines, there are still some working in the United States, particularly in large inaccessible areas of wilderness, as found, for example, in the Sierra Nevada. Amish farmers and US marines also still recognise the great value of mules. 

Finally, I'm pleased to note that in 1985 President Reagan proclaimed October 26th as National Mule Day; something you'd have to be an ass not to celebrate.  

Note: for a sister post to this one on mules (as footwear), click here. 

On Pythons in the Everglades

An adult female Burmese python captured in the Everglades

Photo: Wayne Lynch / Getty Images / All Canada Photos

As a life-long ophidiophile, any newspaper headline that contains the words hybrid python or super-snake is sure to attract my attention. 

And thus it was that I found myself excitedly reading a story in today's Guardian about a recent US study into non-native species that has discovered that some specimens of python slithering around the Florida Everglades are a genetic mixture of two species, potentially making it an even more formidable creature; one that is perfectly adapted to its sub-tropical environment;        

I appreciate that the good people of the Sunshine State may feel that they already have enough exotic fauna to contend with - a million alligators, giant carnivorous lizards and poisonous tree frogs, etc. - but I couldn't help smiling at the thought of this new and improved (all-American) snake feasting on the local wildlife and asserting itself as the region's apex predator, full of hybrid vigour.         

Apparently, researchers had expected to discover the snakes were pure Burmese python. Instead, they were surprised to discover the genetic signature of the Indian rock python also present; a smaller, faster, more aggressive creature that prefers to live on higher, dryer ground than its Burmese cousin. 

For those who hate the thought of invasive species and hybridisation - and who would, if they could, exterminate every last python in Florida - this is obviously an unwelcome development. But there's not much that can be done; the estimated 300,000 pythons that occupy the waterways of a 1.5 million acre wilderness cannot all be captured or killed. The population is thus only likely to grow, expanding its range northwards.

Still, every Eden needs its serpent, as they say ... And besides, Florida's 500,000 feral pigs are probably a bigger threat to the Everglades than pythons - at least until the latter eat them.

See: Richard Luscombe, 'Super-snake: hybrid pythons could pose new threat to Florida Everglades', The Guardian (25 Aug 2018): click here to read online.  

On Archaic Human Interbreeding

Photo credit: Neanderthal Museum (Mettmann, Germany)

www.neanderthalmuseum.info

As regular readers of this blog will know, torpedo the ark means (amongst other things) destroying the inbred and incestuous ideal of purity and celebrating the enhanced effects of diversity, deviance and hybrid vigour.

Thus I'm always interested to read studies that lend support to the possibility of sexual shenanigans (and thus genetic exchange) between different archaic human populations; i.e. of homo sapiens copping off with Neanderthals, Denisovans, and who knows who (or what) else in the promiscuous, prehistorical past. It's rather nice to think that the modern human genome carries a small percentage of DNA from now extinct species that were pretty much but not quite human in the same way as us.

Of course, I'm aware that some researchers like to argue that observable genetic affinities between archaic and modern human populations are in fact explainable in terms of common ancestral polymorphisms - and not admixture - but even they cannot rule out the possibility of introgressive hybridization due to some degree of fucking around and that thought makes me smile. 

However, just to be clear, I'm not saying that all passionate encounters with strangers make happy or that heterosis always makes healthy. It's now thought, for example, that modern man's proneness to allergies is due to the presence of three genes picked up from Neanderthal lovers - that hay fever is a sign not so much of our own hypersensitivity, but of the brute in us!

But inbreeding is far more likely to end in depression and reduced biological fitness than mixing things up a little; even the three genes mentioned above that cause some of us to itch and sneeze every summer, must also have conferred some evolutionary advantage (probably boosting the immune system, since they are involved in the body's defence system against pathogens).

So, to conclude: we should be grateful to our ancient ancestors who took the risk of loving those outside their own family, tribe, race, or species. Without such pioneers in perversity, we wouldn't be where we are today ...


This post was suggested to me by Dr Andrew Greenfield, to whom I am very grateful.

Heterosis

Luma Grothe: the lovely face of fashion 

and Irma Grese: the ugly face of fascism

Nazis are obsessed with blood: both spilling the blood of others deemed racial inferiors and preserving the purity of their own blood, which is thought to possess superior qualities and derive from a divine origin. For the Nazis, therefore, the most dreadful thing in the world is the prospect of interracial sexual relations between people of Nordic stock and those who are of non-Aryan descent. They described this as a form of Rassenschande - an infringement upon the laws of Nature which Nazi policies of racial hygiene were designed to vigorously uphold and enforce.

German girls were warned that should they commit blood treason and choose to fuck with racial inferiors, not only would they be forever lost to their own people, but any unfortunate child that resulted from the illicit union would be a lamentable creature, fit only for extermination. Such irresponsible actions also had a far wider consequence: Hitler identified miscegenation as the sole cause of cultural destruction; "for men do not perish as a result of lost wars, but by the loss of that force of resistance which is contained only in pure blood."

Despite the pseudo-biology used to provide a scientific basis for these beliefs, they are, of course, little more than pernicious fantasies. The fact is many mixed race individuals exhibit not only extraordinary beauty - as in the case of Luma Grothe, pictured above - but what is known as hybrid vigour. In other words, certain traits are enhanced as a result of the dissimilarity in the gametes by whose union the organism was formed.

Now, this is not to say that all such unions produce supermodels. But, by and large, it’s inbreeding that’s genetically problematic rather than outcrossing. For it’s the latter practice that increases diversity and promises heterotic wonders, such as Miss Grothe, born under sunny South American skies to a German mother and a father of Japanese and African descent.

Ultimately, if given the choice between the above and Irma Grese - the blonde, blue-eyed Beast of Belsen - I know whom I’d choose to share a world with ...

Note: The line quoted from Hitler can be found in Vol. 1, Chapter 11, of Mein Kampf, trans. Ralph Manheim, (Hutchinson, 1969), p. 269.