Seashells and Sunflowers | Necochea, Argentina

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Argentina's Role in the History of Fingerprinting

As part of the complicated process to obtain permanent residency in Argentina, I must submit a criminal background check from the FBI to Argentine immigration officials. In order to request this document, I had to be fingerprinted at the local police station, a task I conveniently took care of while back visiting the U.S. in August. With ink-stained fingers the order of the day, the fingerprinting process proved a rather messy affair to be sure, although not a terribly complicated one.

Fingerprinting methods – both traditional "ink and roll" and digital – now form part of standard procedures at government and law enforcement agencies around the world. While DNA testing has revolutionized the field of forensics, fingerprint analysis remains one of the most reliable crime-fighting and personal identification tools available to the police. In fact, the use of fingerprints to nab criminals dates back over a century.

But did you know that Argentina – and even more unlikely, my adopted home of Necochea – played a pivotal role in the history of fingerprinting? It all boils down to a good, old-fashioned murder mystery, but first, here's some background.

One of the pioneers of fingerprinting, Juan Vucetich, a Croatian-born police investigator and official who immigrated to Argentina, made a significant contribution to the development of fingerprint science. In 1891, based on work by Sir Francis Galton, Vucetich developed a fingerprint classification and filing system for both criminal justice and civil applications, including an immigrant tracking system. Vucetich's system proved highly useful, when just months following its creation, an Argentine detective employed the new method to solve the very first criminal case in the world using fingerprint evidence, right here in Necochea.

Here's an excerpt of "South Atlantic Crossings: Fingerprints, Science, and the State in Turn-of-the-Century Argentina" from the American Historical Review, an excellent article about Argentina's contributions to the science of fingerprinting, which explains the details of this history-making case:

"In the course of one of the most infamous murder cases in late nineteenth-century Argentina, prosecutors obtained in 1892 the world's first criminal conviction based on fingerprint evidence. Immersed in the ghoulish facts of the case, in which two small children were stabbed to death in their beds, the coastal villagers of Necochea in Buenos Aires Province hardly noted this high-water mark of transatlantic science. But it was from here that the first practical applications of fingerprinting burst forth, a vital eddy in the currents of people, ideas, and technologies surging across the Atlantic at the turn of the century.

The case had been initially vexing: no one had seen the crime, and interrogations had yielded contradictory evidence. Amid the gore, however, was a single bloody fingerprint left on a doorjamb. How, short of finding blood on the suspect, could a match be proved?

Several days into the investigation, the detective in charge, Eduardo M. Alvarez, shocked observers with a novel brand of evidence, a method of linking finger marks to police records of known or suspected criminals. He demonstrated a match between the bloody mark and the prints of the children's mother, Francesca Rojas, who promptly confessed to the crime."

Vucetich went on to publish a book outlining his methods entitled Dactiloscopía Comparada (Comparative Dactyloscopy), and his fingerprinting classification system eventually gained acceptance throughout Latin America and Europe. The Vucetich system is still in use today, primarily in South America.

If you're interested in learning more about the history of fingerprinting, click here for information from Interpol.

Random side note: "Tocar el piano/pianito" is a slang way of saying "to be fingerprinted" in Spanish (literally "to play the [little] piano," as the action of being fingerprinted bears resemblance to tickling the ivories.)

[Photo credit: Jack Spades, Wikipedia Creative Commons]

Vintage Photos of Argentina

Some time ago, I confessed my love of vintage photographs. In my quest to uncover more vintage goodness, I decided to delve into The Commons on Flickr, a collection of publicly-held images submitted by museums and other cultural organizations from around the world. Friends, I can happily report that I have struck the mother lode.

I found a fascinating series of images from Argentina that dates to the 1920s, culled entirely from the archives of Chicago's Field Museum Library. I was also excited to note that many of the photographs were taken in and around Necochea and Quequén.

Argentina is rich with fossils—a paleontologist's dream, really—and the Field Museum sent two small teams of scientists to undertake fossil-collecting expeditions that spanned several years and numerous provinces: The Captain Marshall Field Expedition for Vertebrate Paleontology (1922-1925), and The 2nd Captain Marshall Field Paleontological Expedition (1926). It seems that the efforts of the second expedition were primarily focused on sites in Catamarca (northwestern Argentina) and the province of Buenos Aires, including towns such as Necochea, Quequén, and Monte Hermoso.

Although the men were obviously here for scientific purposes, they also managed to capture some wonderful scenes from everyday life in Argentina at the turn of the 20th century. Here are just a few of the many photos from Necochea and Quequén:

[Horse-drawn wagons carrying wheat to the port for shipment – Puerto Quequén – 1926]

[Swimming races – 1926]

[Elmer Riggs, expedition leader, standing by a large natural arch – coast of Necochea – 1926]

[Scene on Río Quequén Grande, near camp – present-day Paraje Las Cascadas – 1926]

[At the site of the Megatherium excavation – bank of the Río Quequén Salado]

Explore some of the 200+ vintage images from all over Argentina that are available on The Commons at Flickr.

16 Tons of Dinosaur Bones from Argentina Arrive in Philadelphia

A shipment of dinosaur fossils arrived today in Philadelphia after a three-week journey from Patagonia, Argentina. The bones were unearthed by paleontologists from Drexel University (kudos to my alma mater!) over a five-year period. The remains weigh in at a staggering 16 tons, and they belong to the second heaviest dino ever found.

Read more about the dig in this Drexel University press release.

[Photo credit: Drexel University]

The Science Behind Life Below the Equator

Today I'm going to get a little nerdy on you guys. Ok, really nerdy. What can I say? My dad is a retired earth science professor. I come by it honestly.

These days I'm not just far from where I grew up—I'm living in a completely different hemisphere! To be exact, my adopted home of Necochea has a latitude of 38° 33' S, as compared to Philadelphia's latitude of 39° 57' N. Though the two locations are virtually the same distance from the equator, living south of that imaginary line makes all the difference, with profound implications ranging from what the sky looks like at night to animal migration patterns.

Let's take a look at four aspects of the natural world that differ in the southern hemisphere. I've done my best to provide you with reputable scientific sources about each phenomenon so you can indulge your inner nerd and explore further if you so choose.

Reversal of the Seasons

The seasons are reversed in the northern and southern hemispheres; when it is winter in the northern hemisphere, it is summer in the southern hemisphere, and vice versa. The fine folks at the Lunar and Planetary Institute in Houston, TX have written up a very clear explanation of the causes of this phenomenon, so rather than reinvent the wheel, I'm going to direct you here to read all about it.

Opposing seasons turn things topsy-turvy when it comes to holidays. For example, most of the classic symbols of Christmas and Easter are strongly linked to the northern hemisphere seasons in which they're celebrated. While you're all dreaming of a white Christmas, we're seriously thinking about heading to the beach to escape the heat (though this is also true for those of you living in the tropics).

The influence of the reversal of seasons extends to the academic calendar as well. In Argentina, the school year gets underway in March and finishes up in December, with students enjoying an extended summer break just like their counterparts in the northern hemisphere.

The Coriolis Effect

If you ask someone to describe the Coriolis effect, his response (if it's not a blank stare) will be something like this: "The Earth's rotation causes the water in a sink or toilet to drain in one direction in the northern hemisphere and in the opposite direction in the southern hemisphere." If you need to brush up on your physics, the University Corporation for Atmospheric Research offers an accurate description of the Coriolis effect.

I hate to be the bearer of bad news, but the Coriolis effect does not influence the direction that water drains in a sink or toilet. The professors at Penn State University want you to know that although in theory water should drain in opposite directions in the two hemispheres, in practice it is very difficult to demonstrate this phenomenon due to differences in toilet and sink design that easily overcome the relatively weak Coriolis force.

While you're unlikely to catch the Coriolis effect at work while staring into the toilet, you may have better luck if you flip to the Weather Channel. "The rotation of the Earth does influence the direction of rotation of large weather systems and large vortices in the oceans, for these are very long-lived phenomena and so allow the very weak Coriolis force to produce a significant effect, with time." [1] As a result, hurricanes and tropical storms that form in the southern hemisphere spin clockwise while those that form in the northern hemisphere spin counterclockwise.

The Night Sky

Most people aren't terribly adept at picking out constellations in the night sky, but just about everyone who lives in the northern hemisphere is familiar with the Big Dipper (Ursa Major) and the North Star (Polaris). However, I suggest you don't go looking for the Big Dipper here in Argentina—you won't find it.

Instead, if you look to the south, you'll be treated to a view of the Southern Cross (Crux), one of the most recognizable constellations in the southern hemisphere. "It is easy to locate simply by looking for four bright stars all less than five degrees apart. Five degrees is about the width of your three middle fingers held at arm's length." [2] As with most constellations, you'll have to use your imagination, but if you picture a cross lying on its side in the upper left-hand corner of the photo below, there you have it.

"Because it is not visible from most latitudes in the northern hemisphere, Crux is a modern constellation and has no Greek or Roman myths associated with it. Crux was used by explorers of the southern hemisphere to point south since, unlike the north celestial pole, the south celestial pole is not marked by any bright star." [3]

Much to my delight, my favorite constellation Orion is visible in both hemispheres; however, Orion looks a bit different here. Viewing the constellation from my perspective here in the southern hemisphere, Orion is upside down.

This article highlights differences between the night sky in the northern and southern hemispheres.

Animal Migration

Down here below the equator, even the migratory habits of the critters are different. Humpback whales spend the southern hemisphere summer in the food-rich waters of the Antarctic, and then they head north to balmier climes for breeding season. [4]

In terms of our fine feathered friends, it seems that "bird migration is a mainly northern hemisphere phenomenon. The lack of wide expanses of land in the southern hemisphere leads to a more stable climate and less overall seasonal movement of organisms." [5] Those species that do migrate to escape colder temperatures head north rather than south.