April 12, 2010

The Zanclean Flood

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Periodically throughout history the Mediterranean Sea has been closed off from the Atlantic Ocean by the continued northward movement of the African Tectonic Plate into the Eurasian Tectonic Plate. When this happens the Mediterranean Sea slowly begins to evaporate. Over the course of a thousand years or so it dries out nearly completely.


This produces a huge desert that is 3-5 km below sea level. Possibly some incredibly salty lakes also. Near the bottom the air pressure would be about 150% of that at sea level and the adiabatically heated air would have reached 80°C (176 °F) in the summer. This set of circumstances is known as The Messinian Salinity Crisis.


About 5.3 million years ago this crisis came to an end when the waters of the Atlantic found their way into the empty basin through erosion. At first just a trickle which eroded a deeper channel, which brought more and more water until there was a 200 km wide waterfall pouring unbelievable volumes of water into the basin. This catastrophic flood is known as The Zanclean Flood. The channel cut by the flood still exists today in the form of The Strait of Gibraltar.

Posted on April 12, 2010 11:52 PM | | Comments (0)

April 8, 2010

Nature by the Numbers

Presented without comment. The video is by Cristóbal Vila. The music is "Often a Bird" by Wim Mertens.

Posted on April 8, 2010 6:25 PM | | Comments (0)

The Freedom of the City

Freedom of the City is an honor bestowed on esteemed members of the community by a number of commonwealth nations. The practice dates back to a Roman military privilege that allowed especially loyal or trustworthy military units to enter the city under arms.

Of interest is The Freedom of the City of London which comes with some interesting apocryphal rights including:


  • The right to herd sheep over London bridge

  • The right to go about the City with a drawn sword

  • The right to be hung with a silken rope if ever convicted of a capital offence

  • Immunity to being press-ganged

  • The right to be married in St Paul's Cathedral

  • The right to be buried in the City

  • The right to be drunk and disorderly without fear of arrest.

The evidence that these rights were honored in the past is shaky, but they are interesting none the less.

Posted on April 8, 2010 4:33 PM | | Comments (0)

September 11, 2009

The Dozenal Society of America

dozenal logo


Certainly binary and octal counting are much too easy. Do you think that even hexadecimal lacks a certain je ne sais quoi? Then maybe the Dozenal Society of America is for you.

Posted on September 11, 2009 6:58 PM | | Comments (0)

July 3, 2009

The great Richard Feynman on doubt, uncertainty, and religion


Preach on Professor Feynman.

Posted on July 3, 2009 4:35 PM | | Comments (0)

June 2, 2009

The Smell of Rain

You learn something new every day. The scent of rain is caused by a collection of botanical oils called petrichor mixed with the organic compound geosmin. These compounds are
kicked up from the earth by rain and are particularly pronounced following the first rain after a long dry spell.

See also: this article on TYWKIWDBI.

Posted on June 2, 2009 11:55 PM | | Comments (0)

Neurotoxic Honey

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Another excellent article over at the mind hacks blog. As it turns out, honey derived from the blossoms of Rhododendron ponticum contain the neurotoxin Grayanotoxin.

This "maddening honey" was known to the ancients. Pliny the Elder wrote of it in his Naturalis Historia, a translation of which can be found here.

It may also be the case that honey produced from the flowers of nerium oleander or the almond tree (prunus dulcis) contains neurotoxins.

Posted on June 2, 2009 9:41 PM | | Comments (0)

March 28, 2009

Music and Language

Some new research seems to indicate that the natural vowel formats used in language may inform our appreciation for music.

Despite the wide variety of sounds in different languages, and the even greater variety in people's voices, the formants of their vowels fall into narrow and defined ranges of frequencies. The first one always has a frequency of 200-1,000 Hz, while the second always lies between 800 and 3,000 Hz.

Ross analysed the formants of English vowels by asking 10 English speakers to read out thousands of different words and some longer monologues. Amazingly, she found that the ratio of the first two formants in English vowels tends to fall within one of the intervals of the chromatic scale.

When people say the 'o' sound in rod, the ratio between the first two formants corresponds to a major sixth - the interval between C and A. When they say the 'oo' sound in booed, the ratio matches a major third - the gap between C and E. Ross found that every two in three vowel sounds contain a hidden musical interval.

Her results didn't just apply to English either. Ross repeated her experiments with people who spoke Mandarin, a vastly different language where speakers use four different tones to change the meaning of each word.

Even so, Ross still found musical intervals within the formant ratios of Mandarin vowels. The distribution of the ratios was even similar - in both languages, an octave gap was most common, while minor sixth was fairly uncommon.

Link to full article.

Posted on March 28, 2009 8:03 PM | | Comments (0)

March 24, 2009

The Origin of Chili Peppers

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Smithsonian Magazine has a fascinating article about the origin of the capsaicin secreting glands found in the fruit of plants which are members of genus capsicum.

It was long believed that these glands improved survivability by deterring seed predators such as rodents, but new evidence points to improved survivability due to the anti-fungal properties of capsaicin providing protection from seed rot caused by a member of genus fusarium.

Posted on March 24, 2009 11:09 PM | | Comments (0)

February 5, 2009

Spookfish Evolves Two Chambered Eye, Uses Crystal Mirrors Instead of Lenses

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To complete the interesting animal trifecta I bring you the Brownsnout Spookfish (Dolichopteryx longipes).

This animal is an incredible testament to the amazing power of evolution. Living very deep in the ocean means that the ability to collect light with its eyes is very important. It has two adaptations that each help with this task.

First it has developed a second eye chamber (they both share the same retina covered in light receptive cells). This allows one chamber to collect light from above in order to catch a glimpse of predators before they attack while the other chamber collects light from below where bioluminescent food may be found.

Second, the new downward facing chamber originally had no lens which made it only somewhat effective at collecting light. Likely it could only see things below which were very close or very bright. However, over the eons the creature has evolved a mirror-like array of crystals in the second chamber that allow it to effectively collect light from below. Very cool.

This post over at Science Blogs has more info.

Posted on February 5, 2009 5:18 AM | | Comments (0)