Tag: evolution

Whispers of the dragon

Posted on by Eleni Petrakou

by Eleni Petrakou

Detail of painting in medieveal style. A person with rich elegant clothes, seen from the bust down, is holding a small dragon from a leash in the fashion of a pet.
Detail from “The Grandes Heures of Anne of Brittany” by Jean Bourdichon, c. 1505.

During this Chinese New Year celebrations, this columnist was very surprised to realize that what dragons were is not really common knowledge.

Are you one of those people who don’t know? I’m glad you are here. Already know? A refresher is always pleasant on this particular topic.

Thinking of it, I was probably spoiled. I happened to get exposed to the answer before I thought of the actual question; all by reading Carl Sagan’s stunning “The Dragons of Eden” at a young age.

But, notwithstanding, I mean, what could dragons be other than dinosaurs.

*

For millennia, unrelated civilizations around the globe have been painting dragons at every chance they get. Ever since we found out about dinosaurs we’ve been doing the same with them. Kids are enamored. Toys, cartoons, grown-up science articles abound. It’s impossible to go a single day without a dinosaur, in some artistic form or other, entering our field of vision. Today I saw three. Plus two dragon tattoos.

The obvious physical similarity between the two creatures probably renders any further arguments redundant. (But it’s interesting to add that one ingredient in traditional chinese medicine used to be dragon bones; and it was powdered dinosaur fossils.) The question is not “whether” but “how on earth”. How was it possible for humankind to retain the image of creatures separated from it by tens of millions years?

Although I don’t know the answer, “The Dragons of Eden” looked at a few more hints of this peculiar survival in our species’ collective memory bank. They mostly have to do with snakes, the “evil lizards’” direct descendants. Read more »



Monday, September 25, 2023

Grand Observations: Darwin and Fitzroy

Posted on by Mark Harvey

by Mark Harvey

Captain Robert Fitzroy

One of the artifacts of modern American culture is the digital clutter that crowds our minds and crowds our days. I’m old enough to have grown up in the era before even answering machines and the glorification of fast information. It’s an era that’s hard to remember because like most Americans, I’ve gotten lost in the sea of immediate “content” and the vast body of information at our fingertips and on our phones. While it’s a delicious feeling to be able to access almost every bit of knowledge acquired by humankind over the last few thousand years, I suspect the resulting mental clutter has in many ways made us just plain dumber. Our little brains can absorb and process a lot of information but digesting the massive amount of data available nowadays has some of our minds resembling the storage units of hoarders: an unholy mess of useless facts and impressions guarded in a dark space with a lost key.

If you consider who our “wise men” and “wise women” are these days, they sure seem dumber than men and women of past centuries. I guess some of them are incredibly clever when it comes to computers, material science, genetic engineering, and the like. But when it comes to big-picture thinking, even the most glorified billionaires just seem foolish. And our batch of politicians even more so.

It’s hard to know the shape and content of the human mind in our millions of years of development but the story goes that we’ve advanced in consciousness almost every century, with major advances in periods such as the Renaissance and the Enlightenment. That may be true for certain individuals but as a whole, it seems we drove right on past the bus stop of higher consciousness with our digital orgy and embryonic embrace of artificial intelligence. Are we losing the wonderful feeling, agency, and utility of uncluttered minds? Read more »

Monday, April 13, 2020

The greatest artist

Posted on by Ashutosh Jogalekar

by Ashutosh Jogalekar

A dinosaur fossil found in China with a clearly visible feathered exterior (Cosmos Magazine)

Neil Shubin’s “Some Assembly Required” is a delightful book whose thesis can be summarized in one word – “repurposing”. As Steve Jobs once put it, “Good artists create. Great artists steal”. By that reckoning Nature is undoubtedly the most magnificent thief and the greatest artist of all time. Repurposing in the history of life will undoubtedly become one of the great paradigms of science, and its discovery has not only provided immense insights into evolutionary biology but also promises to make key contributions to our understanding and treatment of human disease.

Among many other achievements of Darwin’s great theory was the explanation and prediction that similar parts of organisms had similar functions even if they might have looked different. One of the truly remarkable features of “On the Origin of Species” is how Darwin gets almost everything right, how even throwaway lines attest to a level of understanding of life that was solidified only decades after this death. The idea of repurposing came about in the “Origin” partly as a reply to objections raised by  a man named St. George Jackson Mivart. Mivart was in the curious position of being a man of the cloth who had first wholeheartedly embraced Darwin’s theory and studied with Thomas Henry Huxley, Darwin’s most ardent champion, before then rejecting it and mounting an attack on it, timidly at first and then vociferously. Mivart’s own tract on the subject, “On the Genesis of Species” made his not-so-subtle dig at Darwin’s book clear.

Darwin’s response to Mivart’s objections in the “Origin of Species” (from the author’s collection; 1882 edition)

Mivart’s basic objection was similar to that raised then and later by creationists. Darwin’s theory crucially relied on transitional forms that enabled major leaps in life’s history; from fish to amphibian for instance or from arboreal life to terrestrial life. But in Mivart’s view, any such major transition would involve not just a sudden change in one crucial body part, say from gills to lungs, but a change in multiple body parts. Clearly the transition from water to land for instance involved hundreds if not thousands of changes in organs and structures for locomotion, feeding and breathing. But how could all these changes arise out of thin air? How could gills for instance suddenly turn into lungs in the first lucky fish that crawled out of water and learnt how to survive on land? This problem according to Mivart was insurmountable and a fatal flaw in Darwin’s theory. Darwin took Mivart’s objections seriously enough to include a substantial section addressing them in the sixth and definitive edition of his book, first published in 1872. In it he acknowledged Mivart’s problems with his theory, and then did away with them succinctly: There is no problem imagining organs being used in different species, Darwin said, as long as they are “accompanied by a change in function.” In writing this Darwin was even further ahead of his time than he imagined. Read more »

Monday, January 20, 2020

The Fermi-Pasta-Ulam-Tsingou problem: A foray into the beautifully simple and the simply beautiful

Posted on by Ashutosh Jogalekar

by Ashutosh Jogalekar

In November 1918, a 17-year-student from Rome sat for the entrance examination of the Scuola Normale Superiore in Pisa, Italy’s most prestigious science institution. Students applying to the institute had to write an essay on a topic that the examiners picked. The topics were usually quite general, so the students had considerable leeway. Most students wrote about well-known subjects that they had already learnt about in high school. But this student was different. The title of the topic he had been given was “Characteristics of Sound”, and instead of stating basic facts about sound, he “set forth the partial differential equation of a vibrating rod and solved it using Fourier analysis, finding the eigenvalues and eigenfrequencies. The entire essay continued on this level which would have been creditable for a doctoral examination.” The man writing these words was the 17-year-old’s future student, friend and Nobel laureate, Emilio Segre. The student was Enrico Fermi. The examiner was so startled by the originality and sophistication of Fermi’s analysis that he broke precedent and invited the boy to meet him in his office, partly to make sure that the essay had not been plagiarized. After convincing himself that Enrico had done the work himself, the examiner congratulated him and predicted that he would become an important scientist.

Twenty five years later Fermi was indeed an important scientist, so important in fact that J. Robert Oppenheimer had created an entire division called F-Division under his name at Los Alamos, New Mexico to harness his unique talents for the Manhattan Project. By that time the Italian emigre was the world’s foremost nuclear physicist as well as perhaps the only universalist in physics – in the words of a recent admiring biographer, “the last man who knew everything”. He had led the creation of the world’s first nuclear reactor in a squash court at the University of Chicago in 1942 and had won a Nobel Prize in 1938 for his work on using neutrons to breed new elements, laying the foundations of the atomic age. Read more »

Monday, August 12, 2013

Creationism as conspiracy theory – the case of the peppered moth

Posted on by Paul Braterman

Addendum: On the day this item was posted, a school board member in Nebraska used slides of Well’s Icons of Evolution to argue that the school should teach “the evidence for and against neo-Darwinian evolution;” details here and here.

by Paul Braterman

Lichte_en_zwarte_versie_berkenspanner

Comparison of carbonaria and typica mounted against post-industrial treetrunk, 2006. Licenced under GFDL by the author, Martinowski at nl.wikipedia. [Click image to enlarge.]

The peppered moth provides a textbook example of industrial melanism and its reversal. Once a classroom classic, then much criticised, and finally rehabilitated through further observation, the story also shows how real science works. The response of the creationist and “Intelligent Design” community provides a textbook example of a conspiracy theory in action, with cherry-picked quotations, allegations of collusion and fraud, and refusal to acknowledge new evidence.

This moth comes in two main varieties, mottled pale (typica), and dark-coloured (carbonaria). The dark form was first noticed, as a rarety, in 1848. Then came widescale industrialisation and grime. By 1895, 98% of the peppered moths in Manchester were dark, and in 1896 it was first suggested that this was a camouflage effect; typica is well concealed against a pre-industrial treetrunk, with its mottling of lichen, but against a sooty background it is an obvious meal for any passing bird. J.B.S. Haldane, in 1924, applied his new methods of quantitative genetics to the speed of such changes, and inferred that carbonaria must have possessed something like 50% per generation advantage over its pallid competitor. An extreme case of Darwinian evolution.

(Let me define that term, since for their own reasons creationists habitually equate all modern biology with Darwin. Darwinian evolution requires just three components; inheritable variation within a population, competition between its members to survive and reproduce, and a difference in fitness between variants. Fitness, here, is simply the ability to survive and have offspring that are themselves fit. This then leads to the evolution of a population in which the variations that confer fitness have become more common. We now know, as Darwin did not, that the inheritable variation corresponds to differences in genes, and that mutations, arising from gene copying errors, give rise to an ongoing supply of new variations. That’s it.)

In the 1950s, Bernard Kettlewell, medical student turned naturalist, carried out a set of direct experiments to test the suggestion that industrial melanism was the result of selective predation. He released large numbers of moths, a mixture of typica and carbonaria, in both polluted and unpolluted woodlands. As expected if the predation-selection mechanism is operating, the survival rate was greater for typica in clean environments, while the opposite applied in environments that were polluted. Kettlewell then persuaded Niko Tinbergen to film the actual process in both kinds of environment. Tinbergen later shared the 1973 Nobel Prize for his work on supernormal stimuli (exaggerated forms preferred to the real ones), along with Konrad Lorentz (filial imprinting) and Karl von Frisch (bee signalling).

Subsequent decades saw the passage of clean air acts, the washing clean of trees by unpolluted rainwater and the return of lichens, and a recovery of the numbers of typica at the expense of carbonaria.

So here we had the clearest possible example of Darwinian evolution in action. Variation dependent on a single gene; a selection pressure, namely predation by birds; an evolved response, namely camouflage; and a change in the direction of evolution with circumstances as camouflage favoured first one variant, then the other. Or so it seemed.

Read more »

Monday, September 6, 2010

And Another ‘Thing’ : Sci-Fi Truths and Nature’s Errors

Posted on by Daniel Rourke

by Daniel Rourke

In my last 3quarksdaily article I considered the ability of science-fiction – and the impossible objects it contains – to highlight the gap between us and ‘The Thing Itself’ (the fundamental reality underlying all phenomena). In this follow-up I ask whether the way these fictional ‘Things’ determine their continued existence – by copying, cloning or imitation – can teach us about our conception of nature.

Seth Brundle: What’s there to take? The disease has just revealed its purpose. We don’t have to worry about contagion anymore… I know what the disease wants.

Ronnie: What does the disease want?

Seth Brundle: It wants to… turn me into something else. That’s not too terrible is it? Most people would give anything to be turned into something else.

Ronnie: Turned into what?

Seth Brundle: Whaddaya think? A fly. Am I becoming a hundred-and-eighty-five-pound fly? No, I’m becoming something that never existed before. I’m becoming… Brundlefly. Don’t you think that’s worth a Nobel Prize or two?

The Fly, 1986

In David Cronenberg’s movie The Fly (1986) we watch through slotted fingers as the body of Seth Brundle is horrifically transformed. Piece by piece Seth becomes Brundlefly: a genetic monster, fused together in a teleportation experiment gone awry. In one tele-pod steps Seth, accompanied by an unwelcome house-fly; from the other pod emerges a single Thing born of their two genetic identities. The computer algorithm designed to deconstruct and reconstruct biology as pure matter cannot distinguish between one entity and another. The parable, as Cronenberg draws it, is simple: if all the world is code then ‘all the world’ is all there is.

Vincent Price in 'The Fly', 1958Science fiction is full of liminal beings. Creatures caught in the phase between animal and human, between alien and Earthly, between the material and the spirit. Flowing directly from the patterns of myth Brundlefly is a modern day Minotaur: a manifestation of our deep yearning to coalesce with natural forces we can’t understand. The searing passions of the bull, its towering stature, are fused in the figure of the Minotaur with those of man. The resultant creature is too fearsome for this world, too Earthly to exist in the other, and so is forced to wander through a labyrinth hovering impossibly between the two. Perhaps Brundlefly’s labyrinth is the computer algorithm winding its path through his genetic code. As a liminal being, Brundlefly is capable of understanding both worlds from a sacred position, between realities. His goal is reached, but at a cost too great for an Earthly being to understand. Seth the scientist sacrifices himself and there is no Ariadne’s thread to lead him back.

In her book on monsters, aliens and Others Elaine L. Graham reminds us of the thresholds these ‘Things’ linger on:

“[H]uman imagination, by giving birth to fantastic, monstrous and alien figures, has… always eschewed the fiction of fixed species. Hybrids and monsters are the vehicles through which it is possible to understand the fabricated character of all things, by virtue of the boundaries they cross and the limits they unsettle.”

Elaine L. Graham, Representations of the Post/Human

Read more »