Reflections on the Black Tree Frogs of Chernobyl

A tree frog shown before and after the 

Chernobyl nuclear accident in 1986

 

 

I. 

 

I have always liked D. H. Lawrence's description of little green frogs as gem-like [1].

 

But it seems that the frogs living in the Chernobyl Exclusion Zone (CEZ) are no longer emerald green in colour. For in order to increase their survival rates in an irradiated environment, the frogs have undergone rapid evolution and now model jet black skins rich in protective melanin [2].

 

In 2016, whilst researching the effects over the previous three decades of Chernobyl's uniquely polluted environment on the flora and fauna, two Spanish scientists [3] made a strange discovery ... 

 

They expected to find that plant and animal species subjected to daily doses of radiation way above normal levels would have experienced negative consequences, but what they did not anticipate was that nature would respond in such an amazing way and recover so quickly - and they certainly weren't on the lookout for black frogs!

 

 

II.

 

So, what on earth is going on here? 

 

Well, cancer resistant wolves [4] and ebony-skinned tree frogs would seem to suggest that the Chernobyl disaster, which generated the largest release of radioactive material into the environment in human history, has accelerated natural evolution in a manner that Darwin - who always liked to stress the slow and gradual nature of evolutionary change by natural selection [5] - would have found hard to believe.   

 

And this - along with the absence of human beings - helps to explain why Chernobyl has become one of the largest nature reserves in Europe, where a diverse range of endangered species find refuge and live happily (or at least successfully) side-by-side. 

For whilst acute exposure to high doses of radiation can cerainly be damaging, both to the natural environment and the genetic material of living organisms, it can also kick-start and accelerate evolution in a surprisingly positive way, as species adapt to the new conditions. 

 

 

Notes

 

[1] See D. H. Lawrence, 'The State of Funk', in Late Essays and Articles, ed. James T. Boulton, (Cambridge University Press, 2004), p. 221. 

 

[2] The pigment melanin which, as many people know, reduces the effects of ultraviolet radiation, can also, so it seems, afford protection against ionising radiation. And that's why it's better to be a black frog than a green frog if you're going to spend your life hopping about in the CEZ.   

 

[3] Germán Orizaola and Pablo Burraco; they discuss their study of over 200 male tree frogs taken from twelve different breeding ponds from various sites in northern Ukraine - including four outside the CEZ - in an article originally published on theconversation.com (28 Sept 2022): click here.  

      As Orizaola y Burraco make clear, the dark skin colouration is typical of frogs from within or near the most contaminated areas at the time of the Chernobyl disaster and it suggests that they have undergone a process of rapid evolution in response to the radiation. The black frogs, having better survival rates, are now the dominant type within the CEZ, which, in my view, is a bit of a shame, as I prefer the little frogs with bright green skins. 

 

[4] See the recent post entitled 'Cara Love and the Mutant Wolves of Chernobyl' (14 Feb 2024): click here.

 

[5] In what is considered to be the founding text of evolutionary biology - On the Origin of Species (1859) - Darwin emphasises how natural selection progresses at a glacial pace and we usually observe nothing of the changes being made until long periods of time have passed. 

      Although this is true, adaptation to new conditions can occur within a relatively short period of time and examination of the fossil record shows that many species undergo rapid bursts of evolution, even if true speciation takes time. Recent work in developmental biology has identified certain mechanisms of tissue morphogenesis that may help explain any swift structural transitions. 

      I am grateful to Dr Andy Greenfield - my go to science guy and longtime friend - for his guidance on this point.

 

 

For a frog-related follow-up post to this one, click here.

 

 

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. 

Mules 1: Sex Kitten Shoes

Wandler handmade pink and orange leather mules

with 3" contrast heel and pointed toe

Available at Harvey Nichols: click here

Say the word mules to some people and they'll think of heterotic donkey-horse hybrids that hugely impressed Darwin for - amongst other things - their intelligence, memory, and powers of muscular endurance. 

However, for those philosophers on the catwalk, such as myself, with a mildly fetishistic interest in the history of female fashion, the word refers, of course, to one of the loveliest of shoe designs and surely a staple of every well-dressed woman's wardrobe; from celebrated French beauty Mme. La Comtesse d'Olonne, to Candace Bushnell's fictional alter ego Carrie Bradshaw.       

Backless and usually (but not always) closed-toe, the mule in its modern form was originally worn only within the bedroom; easy to slip on and easy to slip off. But when members of the French court, including Mme. de Pompadour (official mistress to Louis XV) and Marie Antoinette (the last and most stylish Queen of France), began to wear them en dehors de la boudoir, it kickstarted a new trend that has been with us ever since.   

As a man who knows more about women's shoes than most others, Spanish designer Manolo Blahnik once said:

'When a woman wears mules she walks a bit differently. It's very sexy; she has to find her balance. Madame de Pompadour in her mules, walking around Versailles, click! click! click! Can you think of anything more exquisite?'


II.

Perhaps because of their association with the bedroom - and the fact that that they always seem ready to slip off, leaving the foot exposed - mules have an inherent, playful eroticism. We see this, for example, in Fragonard's famous picture The Swing (1767), wherein a young beauty loses a shoe to the delight of her male spectators.   

But mules also figure prominently in the slightly darker corners of the porno-aesthetic imagination, as explored by artists such as Manet, for example in his scandalous painting of 1863 entitled Olympia, in which a confident young prostitute stares provocatively and without shame at the viewer, the nakedness of her flesh emphasised by a bootlace tied like a punk accessory around her neck and a pair of yellow silk mules, one of which she has casually kicked off.       

Finally, we must of course mention the so-called marabou mules of the 1950s, often made from plastic and decorated with feathers, as worn by sex-kittens everywhere (especially in America). In fact, as archivists at the Met Museum rightly say, no object better epitomises the trashy glamour of the time than the marabou mule.  

Amusingly, if you ever buy your groceries on Harold Hill, you'll notice young Essex girls wearing these fluffy symbols of feminine allure as they stroll round Iceland or buy coffee in Greggs.

See: Alice Newell-Hanson, 'In praise of mules, fashion's most perverse shoes', i-D (27 March 2017): click here to read online. 

See also a sister post to this one on mules as noble beasts of burden: click here. 

Chris D. Thomas: Inheritors of the Earth - Six Key Ideas (Part 2: Sections IV-VI)

Chris D. Thomas (Photo: Allen Lane)

IV. Vive la bio-révolution!

According to Chris D. Thomas, we are today in the midst of a great global interchange; a biological coming together, facilitated by humanity, of previously separated species which will conceivably be "the greatest spur to evolution for a hundred or more million years" [169]. Speciation seems to be unfolding in front of us at a pace that Darwin would have found unimaginable, although, of course, the real proliferation of new species will come in a far-distant future.

In another crucially important passage, Thomas writes:

"These new connections are unlike any previous period in the Earth's history. The explosion that killed off the dinosaurs, and the other four major episodes of mass extinction in the last half-billion years, did not transport vast numbers of the survivors around the planet on a timescale of hundreds to thousands of years. There was no equivalent bringing together of species from different regions. ... Given the geographic distances and rapidity of connections that are taking place in the Anthropocene, there is no precedent since multi-cellular life forms colonized the land." [195-96]

He concludes:

"I find it difficult to imagine a period in the entire history of terrestrial life on Earth when the speed of origination of new evolutionary lineages could have been faster, as a result of  the combined forces of populations arriving in new locations and starting to diverge there, the previous residents becoming adapted to the new species that arrive, and new hybrids coming into existence as species meet up for the first time in new habitats and new geographic locations." [196]

In brief: the human era is undoubtedly a time of unusually rapid extinction. But, ultimately, the Anthropocene bio-revolution will almost certainly represent a bright new dawn.


V. On Translating Man Back into Nature

The idealistic separation of man from nature continues to this day, despite the fact that Darwin published his theory of evolution over 150 years ago. Even some philosophers and scientists who really should know better, still insist on the myth of human exceptionalism and regard human abilities and activity as, in some sense, either unnatural or transcendent. Thomas, to his credit, is having none of this:

"When we contemplate the biology and impacts of humans on the Earth, there is no doubting that Homo sapiens is an extremely unusual animal. But at what point in the unbroken sequence of generations should we decide that humans ceased to be part of nature ... There is no scientific or philosophical justification that could be used to separate this continuum of ape-then-human animals into two qualitatively different categories." [207]   

Evolution has been going on long enough so that humans and chimpanzees are recognisably different; but we are still primates, just like them, and whilst it is man who exercises dominion over the Earth, this is still essentially the planet of the apes. And everything that happens upon it - including art, agriculture and architecture - is absolutely natural and represents an "indirect product of evolution" [209]. 

Indeed, even our anthropocentrism has an evolutionary basis; for this will to species self-privileging is shared with other animals: lions, bison, and killer whales, for example, "respond strongly to other members of their own species for exactly the same reasons" [210] we do. When they see others of their own kind, they see potential mates, family members, collaborators, enemies, etc. "Every species is special to itself because the survival of each individual's genes depend on it." [210]

However, whilst evolutionary predisposition encourages us to develop ideas of human uniqueness, it's important to recognise that we are still just animals and that "everything we do ... is natural" [211].


VI. Welcome to Anthropocene Park

Finally, we arrive at the last chapter of Thomas's book, entitled 'Noah's Earth'. Here, and in the Epilogue that follows, he speculates on what we might do today and how the world might look one million years from now. Different, is the answer to the latter question. But difference and becoming isn't something that has been engineered by man. It's built into the very fabric of the universe, including biology.

What we need, therefore, is an environmental philosophy that is based on an acknowledgement of change and the further recognition that change is something beyond good and evil regardless of whether the consequences are beneficial or harmful to human well-being and survival (although, obviously, we will want things to turn out for the best and it's perfectly legitimate for man to attempt to direct life's unfolding in "a desired direction as effectively and efficiently as possible" [230], eradicating deadly new diseases, for example).

As part of this new philosophy, Thomas thinks it worth considering radical conservation projects that don't just try to save a limited number of endangered species in their present location, but dare to move them to new places where they might thrive, just like the yellow-crested cockatoo, for example, which is thriving in Hong Kong, even as it continues a rapid decline in its Indonesian homeland:

"All the many thousands of transported plants and animals that have established populations in new regions have demonstrated time and again that species may flourish outside their historical ranges. In doing so, they normally increase the total number of species that live in each region, they start to evolve into distinct forms and they sometimes hybridize and create new species. Eventually, they will increase the diversity of life on Earth." [235]

And, in the meantime, it means we might get to see African lions hunting in the USA and black rhinos stomping about in Europe. I'm all for that and all for thinking about the creation of new ecosystems and biological communities - including communities made up of deliberately engineered new species (or even extinct species resurrected).

Ultimately, I agree entirely with Professor Thomas that we shouldn't allow those who worry about Frankenstein science prevent us from using all available means to maintain and increase biological diversity in a variety ways that many puritans would regard as not only unconventional, but unnatural and immoral.

See: Chris D. Thomas, Inheritors of the Earth: How Nature is Thriving in an Age of Extinction, (Allen Lane, 2017). All the page numbers given above refer to this edition of the book. 

To read Part 1 of this post (Sections I-III) click here.

Stupid Is As Stupid Does (Notes on the Dunning-Kruger Effect)

I noticed long ago that one of the classic hallmarks or tell-tale signs of stupidity is the failure of a subject to recognise or own up to their own intellectual limitations and to arrogantly believe that they are in fact well-informed and of above average intelligence.  

But what I didn't know, until recently, is that this mix of cognitive misconception and conceit has been closely studied by psychologists and described in detail: the Dunning-Kruger effect refers precisely to the phenomenon wherein idiots cannot accurately evaluate their own capacities or knowledge and suffer from illusions of superiority due to their inability to see what is patently obvious to everyone else; i.e., that they're dimwits.   

Interestingly, the corollary to the D-K effect indicates that gifted people of high ability tend to underestimate or downplay their own competence and mistakenly presume that others can do what they do just as well and just as easily. In other words, intelligent people are often self-effacing and overly generous in their expectations.   

Of course, the fact that fools are often smug and superior in their foolishness had been observed long before Dunning and Kruger formulated their theory in 1999. Poets, philosophers, playwrights and even naturalists such as Darwin have commented on the fact that ignorance more frequently begets confidence than does knowledge.  

But it's Bertrand Russell's remark that has particular resonance today for secularism in the face of religious fundamentalism: "One of the painful things about our time is that those who feel certainty are stupid, and those with any imagination and understanding are filled with doubt and indecision."

See: Kruger, Justin and Dunning, David; 'Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments', in the Journal of Personality and Social Psychology, Vol 77, No. 6, (Dec 1999), pp. 1121-1134. Click here to read.

See also Bertrand Russell; 'The Triumph of Stupidity', in the second volume of Mortals and Others: American Essays, 1931-1935 (Routledge, 1998), where he argues that the essential cause of trouble in the modern world is that "the stupid are cocksure while the intelligent are full of doubt." Click here to read. 

This post was suggested by Dr Andy Greenfield to whom I am grateful.