The Windows to the Soul

The earliest fossil evidence of eyes comes from the Cambrian explosion, around 500 million years ago, their appearance probably driven by the rapidly escalating evolutionary arms race between predators and prey at that time.

From simple eyespots, eyes have evolved into organs of such complexity and precision that they have been put forth as evidence of intelligent design, most famously in William Paley’s 1802 watchmaker analogy. Paley argued that someone coming across a watch on the ground would naturally assume that the watch had a maker. Unlike a nearby rock, the watch is too complex to have formed by natural processes. By the same logic, examples of complexity from life, such as the eye, imply a designer – God.

As has been pointed out in rebuttals from Darwin to Dawkins, given enough time, complexity can arise through the natural process of evolution.

Recent discoveries have shown that eyes are even more complex than previously thought. Ironically, at least some of the complexity appears to have arisen due to ‘flaws’ in the structure of the vertebrate eye.

The vertebrate retina is often said to be built backwards. The light-detecting photoreceptors are at the back of the retina, furthest away from the point at which light enters the eye. Between the photoreceptors and the light source is a mess of neurons and blood vessels that actually obscure the light path.

A 2009 study by Solovei et al found that mice have an unusual distribution of DNA within their photoreceptor cells. Normally within a cell, islands of condensed DNA are distributed within a sea of diffuse DNA. In mouse photoreceptors however, the condensed DNA forms a single central blob. This pattern is not seen in cells from any other part of a mouse’s body and is virtually unknown in multicellular animals.

The colugo or flying lemur is native to southeast Asia.

The group looked at photoreceptor cells from other animals and found a strange correlation. The central blob pattern of DNA also occurred in some other mammals but was absent in fish, birds, reptiles and other vertebrates.

Below is a list of the mammals with and those without the unusual pattern. The members of each group are united by a common behavioural characteristic.

Conventional pattern Unusual pattern
Wild boar Domestic cat
Domestic pig Red fox
Red squirrel Ferret
Chipmunk Velvety free-tailed bat
Woodchuck Domestic mouse
Tree shrew Rabbit
Crab-eating macaque Colugo (flying lemur)
Human Hedgehog tenrec
Guinea pig

Only nocturnal and crepuscular (active at dusk and dawn) mammals have the unusual pattern. There were a few exceptions (horses are crepuscular but have the conventional pattern; cows are diurnal and have an intermediate pattern)

Further analyses showed that the central blob pattern minimises scattering of light passing through the photoreceptor cells. It is most likely an evolutionary adaptation that improves the efficiency of the retina in low light conditions.

Early mammals avoided competition with dinosaurs by exploiting a nocturnal niche. As a result, they developed adaptations to nightlife such as endothermy and a heightened sense of hearing. The changes to photoreceptor DNA probably appeared at this time. After the extinction of dinosaurs, some mammals became predominantly diurnal and reverted to the conventional DNA distribution.

The mammalian eye is a work in progress. Unfortunately, much of the architecture is firmly embedded and so, when circumstances change, some aspects become anachronistic. Any adaptations have to work around these inherent imperfections, a problem that an omniscient designer would be unlikely to face.

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Posted in Nature, Science | Tagged , , | 2 Comments

Pythons in the Everglades

Following on from this post: It’s all very well to be invaded by furry wallabies; it’s a little more concerning when the feral hippo population explodes. But the feral animal problem in the Florida Everglades is the stuff of nightmares. The subtropical wetlands are rapidly being over-run with the world’s largest snakes.

The biggest problem are Burmese pythons which can grow up to nineteen feet in length. Now other species including the African rock python, green and yellow anacondas and boa constrictors are appearing. The snakes were probably released as unwanted pets and are now dominating the Everglades food chain, threatening many native mammals and reptiles. They are even capable of eating American alligators.

The snakes are a potential threat to humans. In 2002, a twenty foot African rock python ate a boy near Durban and there are numerous historical reports of people being eaten by reticulated pythons.

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Hyperekplexia, Latah and the Jumping Frenchmen of Maine

The startle response, the almost instantaneous protective action following a sudden loud noise or other stimulus, is present in many animals. It has evolutionary value in that it enables escape from unanticipated dangers such as the sudden appearance of a predator. In humans, its purpose seems to be to make us look slightly silly when a car backfires.

Like other reflexes, the startle response is involuntary. To minimise response time it follows an abbreviated neural pathway emanating from the brainstem. Sometimes, neurological abnormalities disrupt this pathway leading to some bizarre outcomes.

Hyperekplexia is characterised by an exaggerated startle reflex resulting in a paralysing stiffening of the body. Sufferers are sometimes injured from falls. Fainting  goat syndrome is an unrelated disorder but with similar outcomes.

The Jumping Frenchmen of Maine refers to another abnormal response to the startle reflex. Instead of paralysis, sufferers become highly suggestible. First noticed in lumber camps in northern Maine in the late nineteenth century, there remains some doubt as to whether it has neurological or psychological causes. For a few seconds after being startled, sufferers will obey commands to jump, throw objects or strike someone. Alternatively, they may involuntarily copy someone’s speech (echolalia) or actions (echopraxia).

Similar conditions occur in Indonesia and Malaysia (where it is called latah), northern Japan and other parts of Asia. Sufferers of latah fall into a trance-like state when startled and may display echolalia and echopraxia or may strike out or kick at those around them. An episode can last for as long as thirty minutes. Latah and related conditions are considered culture-bound syndromes as they are only observed in particular cultural settings.

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Lost in Translation

The story goes that when French naturalist Pierre Sonnerat was in Madagascar, he pointed to a large lemur and asked the Malagasy people what it was called. They replied ‘Indri!’ and Sonnerat duly recorded the word. The name stuck and it is still called the indri today. In Malagasy, the word indrý translates as ‘Look, there it is.’

It’s an appealing story and, if true would mean that a humourous mistranslation has been embedded in the animal’s name for over two hundred years (there’s a more dubious story about Joseph Bank’s naming of the kangaroo which supposedly meant either ‘I don’t know,’ ‘Go that way’ or ‘That’s your finger.’) But the more likely explanation is that Sonnerat simply misheard. The Malagasy name for the indri is endrina.

The grizzly bear is often thought to be named due to an aggressive nature and a propensity to mutilate and kill. Hugh Glass, a nineteenth century fur trapper was once mauled by a grizzly before his companions shot it dead. Unconscious and badly injured, he was left in a shallow grave covered with the bear’s pelt. He woke and set his broken leg. The flesh on his back had been ripped off, exposing his ribs. He lay on a rotten log to encourage maggots into the wound which would eat the dead flesh and prevent gangrene. Then, bereft of weapons and food, he crawled and rafted the 320 km to the nearest settlement, arriving six weeks later.

Grizzly means grey, referring to the bear’s hair colour and is unrelated to grisly meaning frightening or gruesome. However, the misunderstanding persists in the bear’s scientific name, Ursus arctus horibilis. In 1815, after examining the specimen brought back with the Lewis and Clarke expedition, George Ord interpreted the word ‘grizzly’ in a report to mean ‘grisly’ and so chose the subspecies name horibilis.

Anyone familiar with the Nintendo character Donkey Kong will know he’s not a donkey. In the original games, he’s a furious ape of the King Kong variety which explains the Kong epithet. A popular explanation for the name is that the Japanese creators intended it to be Monkey Kong but simply used the wrong English word. When Nintendo was sued by Universal Studios for trademark infringement, Donkey Kong’s creator, Shigeru Miyamoto, revealed the origins of the name. He interpreted ‘donkey’ to mean stupid and thought English speakers would understand Donkey Kong to mean ‘stupid ape.’ Despite the loose translations, the success of Donkey Kong saved the struggling company which had begun in 1889 as a manufacturer of playing cards.

Posted in Etymology | Tagged , , ,

Richard Parkers and the Titanic

In 1884, the yacht Mignonette sank en route from Southampton to Sydney. The four-man  crew escaped in a lifeboat with two tins of turnips but no freshwater. Two months later, when they were rescued by a German ship, only three of the crew remained. The seventeen year old cabin boy, Richard Parker, had fallen ill and was killed and eaten by the other three. The resulting criminal case established that necessity is not sufficient defence for murder. Two of the crew were found guilty but served only six months in prison.

Fifty years earlier, Edgar Allan Poe’s novel The Narrative of Arthur Gordon Pym of Nantucket was published. The plot involves the sinking of a whaling ship from which four of the crew survive. As starvation sets in, they draw lots to decide which of them will be killed and cannibalised. The character who draws the short straw is named Richard Parker.

The name Richard Parker has a strange association with naval misfortune. In 1797, he played the central role in a major naval mutiny aboard the Nore for which he was hanged. He drowned after the sinking of the Francis Speight in 1846. As a Bengal tiger, he shares a lifeboat with the only other human survivor in Yann Martel’s 2001 novel Life of Pi (the name of this character was a reference to the previous coincidences).

Richard Parker is also the father of Spider-Man.

Morgan Robertson’s 1898 novella Futility, or the Wreck of the Titan tells the story of an enormous ocean liner named the Titan that sinks in the North Atlantic after hitting an iceberg during its maiden voyage. The Titan was thought to be unsinkable and carried enough lifeboats for less than half the passengers. As a consequence, most of the 2500 passengers drown.

Fourteen years after its publication, the supposedly unsinkable ocean liner Titanic struck an iceberg in the North Atlantic on its maiden voyage and sank. Without enough lifeboats, most of her 2200 passengers drowned.

Posted in Art and Literature, History | Tagged , , , | 1 Comment

Queen Mary’s House

In 1924, work was completed on a new house for Queen Mary, the grandmother of Queen Elizabeth II. The four-storey Palladian villa was designed by one of Britain’s greatest architects, Sir Edwin Lutyens. He employed 200 craftsmen, 700 artists and 600 writers to work on it. The house had running water, working light fittings, a flushable toilet. It was furnished with working clocks, marble floors, a wine cellar, artworks by famous artists and a library stocked with books written by well-known writers exclusively for the house. Limousines were parked in the five-bay garage and the garden was designed by Gertrude Jekyll.

None of this may sound surprising for a house belonging to the British Queen consort until you understand its scale. Known as Queen Mary’s dolls’ house, the structure and everything in it was built to a 1:12 scale. It is in effect a fully functional five foot tall house. The library contains works by W. Somerset Maugham, Aldous Huxley, Rudyard Kipling, Thomas Hardy, J. M. Barrie and M. R. James (Virgina Woolf and George Bernard Shaw declined to contribute). Arthur Conan Doyle’s shortest Sherlock Holmes story is also on the shelf. The bottles in the wine cellar contain real wine (Chateau Lefite and Veuve Clicquot). The toilet is equipped with miniature toilet paper.

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Exhumation and Obsession

Oliver Cromwell

Oliver Cromwell, Lord Protector of the Commonwealth of England, Scotland and Ireland, died in 1658, most likely from septicaemia caused by a urinary infection. Two years later, the Commonwealth collapsed and the monarchy restored, King Charles II decided to execute him.

He had the body exhumed from Westminster Abbey and hanged at Tyburn then decapitated. The rest of his body was thrown into a pit. Cromwell’s head, like Einstein’s brain and the Dauphin’s heart, then had a fairly eventful time. It spent twenty-five years on public display on a pole near Westminster Hall. At some point, it fell off and passed through numerous hands before being buried in 1960.

Pope Formosus

Formosus was pope for a mere five years from 891 until his death in 896 and managed to upset a lot of people in that time. Nevertheless, his treatment after death by Pope Stephen VI, driven largely by a personal hatred, was a little over the top.

In 897, Stephen had Formosus exhumed. The corpse was dressed in papal vestments and placed on a chair. He was then tried for perjury, coveting the papacy and violating church canons.

Since he was dead and couldn’t speak, a deacon was assigned the job of answering for him. Not surprisingly, he was found guilty. He was stripped of his vestments, three of his fingers were cut off and he was reburied. Later, he was exhumed again so that he could be thrown into the Tiber.

Pedro and Inês

Not all exhumations are done out of hatred. For Pedro I of Portugal, it was an obsessive love worthy of a Shakespearean tragedy.

Before he took the throne, Dom Pedro was fated by his father, King Afonso, to marry the Infanta Constança of Castile. But he immediately fell in love with Constança’s lady-in-waiting, Inês de Castro. Alarmed by this, Afonso had Inês murdered. Pedro didn’t take this well and attempted to usurp the throne from Afonso. He failed but Afonso died shortly after.

As king, Pedro then did what any sane person would. He had Inês’ assassins brought before him and personally tore out their hearts. He then had Inês exhumed, dressed in royal garments and placed on a throne. He commanded his vassals to acknowledge her as their queen by kissing the rotting flesh of her hand.

Pedro and Inês now rest in a pair of elaborately carved marble tombs in the Alcobaça Monastery, now a UNESCO World Heritage Site.

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