The genius of Charles Darwin

By the time that an animal had reached, after numberless generations, the deepest recesses, disuse will on this view have more or less perfectly obliterated its eyes, and natural selection will often have affected other changes, such as an increase in the length of antennae or palpi, as compensation for blindness.

The above quote comes from On the Origin of Species. It is just one of the numerous instances where Charles Darwin, on the basis of his theory, makes a wonderful prediction that comes true so many years after the fact. In this case, his prediction has been shown to be true over and over; species which have gone millions of years in the dark lose their eyesight again and again. We see this especially in many species of cave fish, but it isn’t limited to the oceans:

With a leg span of only six centimetres and a body size of around twelve millimetres, the spider Sinopoda scurion is certainly not one of the largest representatives of the huntsman spiders, which include more than 1100 species. However, it is the first of its kind in the world without any eyes.

“I found the spider in a cave in Laos, around 100 kilometres away from the famous Xe Bang Fai cave,” reports Peter Jäger, head of the arachnology section at the Senckenberg Research Institute in Frankfurt. “We already knew of spiders of this genus from other caves, but they always had eyes and complete pigmentation. Sinopoda scurion is the first huntsman spider without eyes.”

One prediction the theory of evolution allows us to make today that Darwin couldn’t make in his lifetime is that the genes for vision in these now-blind species should exist but be broken. If they do not exist, then either there is some really funky timeline and divergence activity (that is, these are old lineages that evolved before their sighted brethren) and we should see a lot of other genetic differences or evolution just isn’t true. Neither one of those options is very likely, of course. What we observe instead is that, indeed, the genes for vision are a broken, jumbled mess. That isn’t the case yet for the above spider because, as far as I know, no such studies have been carried out, but it is the case wherever else these sort of species have had their genes analyzed.

One point I think that needs to be made sure with Darwin’s quote here is this: Natural selection is unlikely to be the only factor in the disappearance of eyes among these species*. In fact, it could have little to nothing to do with the process at all. Vision in the dark is a useless thing, so natural selection may obliterate it for the sake of saving energy or preventing potential injury to a sensitive body part, but I believe it is much more likely that it simply did nothing. It neither selected for nor against vision. As a result of the lack of positive selection, mutation and genetic drift took over and vision in these species simply faded away.

*I really have two points here. First is the one I just made in the above paragraph. Second is the fact that Darwin was referencing natural selection in regard to it creating some compensation for blindness, not in regard to it directionally causing the blindness.


Richard Owen and Gideon Mantell

Richard Owen was one of the great jerks of history. He also happened to coin Dinosauria, from which we get “dinosaur”, he made a number of important scientific discoveries, and he did a great deal in making museums what they are today by way of organizing the Natural History Museum in London. Taken together, we still look back on him with fair acknowledgement for his accomplishments. But, boy, was he ever a jerk.

The man’s heyday was the middle of the 19th century alongside greats like Charles Darwin and Charles Lyell. People tended to recognize Owen’s quality of mind, but they also couldn’t help to notice how petty and vindictive he could be. Cross the man and he would make your life as awful as he possibly could. Just ask Gideon Mantell.

Gideon Mantell made his splash in the sciences long before Owen came on the scene. He discovered the first bits of Iguanodon, a major genus of dinosaur, and is credited with kick starting the study of the ancient monsters before the 19th century had even reached its 25th anniversary.

At first Owen and Mantell were friends. For reasons now lost to time, though, they parted ways, becoming bitter enemies – Owens the more bitter of the two. They both were quite remarkable in their discoveries and descriptions of dinosaurs, giving title to many of the dinosaurs commonly recognized by the layman today. Unfortunately for Mantell, little could keep him from poverty.

As time wore on, Mantell’s health and focus waned. He was a doctor by training – and an excellent one, at that – and he had once run an incredibly successful practice, but his geological and paleontological research got the better of his time. Soon his wife left him, then he found himself suffering from spinal damage after being dragged by a carriage. He was forced to turn his home and all its fossils into a museum to pay his bills, but fearing his status as a gentlemen was in danger he would tend to wave the entrance fee. He eventually sold off most of his collection to the Natural History Museum.

Throughout all this, though, Mantell still wrote and published a number of papers. Unfortunately, he was unable to publish as many as he would have liked because the head of the Royal Society was none other than Richard Owen. Owen did all he could to have Mantell’s papers cast aside. It wouldn’t be long until Mantell could no longer bear the pain of his spine and the burden of Owen’s hatred.

Gideon Mantell took his own life in 1852. His obituary soon followed in the papers and although there was no byline, no one doubted its uncharitable nature was due to Richard Owen. In fact, Owen even transferred claim of a number of discoveries from Mantell to himself. Then, as a final act of indignity, Owen had Mantell’s spine placed in a jar and put on display at the Royal College of Surgeons of England where Owen taught.

Of course, no man could come to be known as one of the most hated and reviled men in scientific history without finding some black mark on his career. For Owen this mark came when it was found that he had failed to credit another scientist with a discovery – a discovery for which Owen had already accepted a prestigious award from the Royal Society. Moreover, he had an ongoing dispute with Thomas Henry Huxley, Darwin’s bulldog. Huxley tended to win the specifics of their dispute, often showing Owen as deceptive in many of his claims. This lowered Owen’s standing as a gentlemen and, in 1862, Huxley managed to have him voted off the Royal Society Council. Few members of the scientific community were saddened.

It was at this point, Mantell long dead, that Owen turned his full attention to the Natural History Museum in London. He continued with his plans to make the museum appealing to the general public rather than simply the scientific community and its followers. It was perhaps some of his greatest work, despite not being the most prominent of his career. He remained at his post in the museum, controversy diminished in his life, until his retirement late in the century.

As for Gideon Mantell’s spine, it was destroyed by the Royal College of Surgeons in 1969 due to the distressingly fitting reason that more space was needed.

Darwin and Lyell

On Charles Lyell, that most eminent of 19th century scientists…

I never forget that almost everything which I have done in science I owe to the study of his great works. Well, he has had a grand and happy career, and no one ever worked with a truer zeal in a noble cause.

~Charles Darwin

Water on the Moon

NASA discovered there is plenty of water on the moon.

Experts have long suspected there was water on the moon. So the thrilling discovery announced Friday sent a ripple of hope for a future astronaut outpost in a place that has always seemed barren and inhospitable.

“We found water. And we didn’t find just a little bit. We found a significant amount,” Anthony Colaprete, lead scientist for the mission, told reporters as he held up a white water bucket for emphasis.

He said the 25 gallons of water the lunar crash kicked up was only what scientists could see from the plumes of the impact.

This is equivalent to roughly a bathtub’s worth of water from this double-impact.

One part of me wants to endlessly speculate at the possibility of microbial life. But all reason and rationality tell me to be cautious. Water does not automatically mean life (especially when its frozen).

…but what if it does mean life, at least in this case? Would the world realize the utter significance of this discovery? Not since Darwin described evolution by natural selection has there been such an important find.