Who says North is “up”?

There are several childhood lessons that I trace back to dinners at Outback Steakhouse: the deliciousness of cheese fries, the inconvenience of being in the middle of a wraparound booth, and the historical contingency of North as “up” on maps.

Who started using the NESW arrangement that is virtually omnipresent on maps today? Was it due to the fact that civilization as we now know it developed in the Northern hemisphere? (Incidentally, that’s why clocks run clockwise–a sundial in the Southern hemisphere goes the other way around.)

That doesn’t appear to be the case according to Nick Danforth, who recently took on this question at al-Jazeera America (via Flowing Data):

There is nothing inevitable or intrinsically correct — not in geographic, cartographic or even philosophical terms — about the north being represented as up, because up on a map is a human construction, not a natural one. Some of the very earliest Egyptian maps show the south as up, presumably equating the Nile’s northward flow with the force of gravity. And there was a long stretch in the medieval era when most European maps were drawn with the east on the top. If there was any doubt about this move’s religious significance, they eliminated it with their maps’ pious illustrations, whether of Adam and Eve or Christ enthroned. In the same period, Arab map makers often drew maps with the south facing up, possibly because this was how the Chinese did it.

So who started putting North up top? According to Danforth, that was Ptolemy:

[He] was a Hellenic cartographer from Egypt whose work in the second century A.D. laid out a systematic approach to mapping the world, complete with intersecting lines of longitude and latitude on a half-eaten-doughnut-shaped projection that reflected the curvature of the earth. The cartographers who made the first big, beautiful maps of the entire world, Old and New — men like Gerardus MercatorHenricus Martellus Germanus and Martin Waldseemuller — were obsessed with Ptolemy. They turned out copies of Ptolemy’s Geography on the newly invented printing press, put his portrait in the corners of their maps and used his writings to fill in places they had never been, even as their own discoveries were revealing the limitations of his work.

map_projectionsPtolemy probably had his reasons, but they are lost to history. As Danforth concludes, “The orientation of our maps, like so many other features of the modern world, arose from the interplay of chance, technology and politics in a way that defies our desire to impose easy or satisfying narratives.” Yet another example of a micro-institution that rules our world.

How to Get FIPS Codes from Latitude and Longitude

FIPS codes are unique identifiers for geographic units within the US. Although they have technically been withdrawn as a standard, they are still widely used in political science and other applications for geographic categorization of data. For example, the CBS/New York Times monthly polling series includes the FIPS code for the county in which each respondent lives.

Say you have some other data with latitude and longitude indicators that you would like to combine with FIPS-coded data. I have written a short Ruby script below that will do exactly this. It assumes that you have your data in .csv format, since that is a pretty generic format and you can usually convert your data to that if it is currently stored in another form. You will also need the Ruby geokit gem:

gem install geokit

Once you have the data ready and the gem installed, you are good to go. Just fill out the lines with comments and run the following from IRB (or however you like to run your Ruby scripts):

require 'geokit'
require 'CSV'

filename = # csv file
fipslist = []

CSV.foreach(filename) do |row|
  lat = # latitude column
  long = # longitude column
  ll = GeoKit::LatLng.new(lat, long)
  fcc = Geokit::Geocoders::FCCGeocoder.reverse_geocode(ll)
  puts fcc.district_fips
  fipslist << fcc.district_fips

You can then do anything you want to with the fipslist object, including writing it out to a file. If you want to share improvements or have questions, please use the comments section below.

What Did Manifest Destiny Look Like?

“Manifest Destiny was the belief widely held by Americans in the 19th century that the United States was destined to expand across the continent. The concept, born out of ‘a sense of mission to redeem the Old World’, was enabled by ‘the potentialities of a new earth for building a new heaven.'” (Wikipedia, citing Frederick Merk)

Now, Michael Porath has told the story of manifest destiny in a series of 141 maps. The main technical trick is that Porath designed the site in HTML5, so it has some nice interactive features. The maps appear on a single page in four columns but you can click any of them for a close-up with an explanation of the changes, or mouse-over a region of the map to see what political entity it was under at the time (e.g. unorganized territory, Spanish colony).

There are two additions that I think would help improve this project. The first is a sense of time scale–some of the maps are only a month apart (January and February 1861, for example) while others are separated by several decades (March 1921 and January 1959). Adding time would allow for a second feature: an animation that would show the areas of change and continuity over time. An excellent example of this is David Sparks’ choropleth maps of presidential voting over time.  I do not know whether this could still be done in Porath’s HTML5 setup, but it is often useful to think about changes to graphical displays (additions or subtractions) that would help to convey meaningful information. What other suggestions do you have for these maps?

Latitude, Longitude, and Culture

It is rare to see a “big idea” in social science that also lends itself to real-world analysis. A pessimistic categorization of the field might group researchers into “storytellers” and “regression runners.” Each group has a few stars who do their work very well, with many more who wish to imitate them. There is little cross-pollination between the groups, however. That is why I was excited to see a pre-print article from the Proceedings of the National Academy of Sciences where a leading empirical researcher, David Laitin, tests a theory of Jared Diamond’s.*

Diamond’s book Guns, Germs, and Steel is part of a genre that tries to explain much of world history in a few themes. Laitin describes one of those ideas in the article’s abstract:

Jared Diamond’s Guns, Germs, and Steel has provided a scientific foundation for answering basic questions, such as why Eurasians colo- nized the global South and not the other way around, and why there is so much variance in economic development across the globe. Diamond’s explanatory variables are: (i) the susceptibility of local wild plants to be developed for self-sufficient agriculture; (ii) the domesticability of large wild animals for food, transport, and agricultural production; and (iii) the relative lengths of the axes of continents with implications for the spread of human populations and technologies. This third “continental axis” thesis is the most difficult of Diamond’s several explanatory factors to test, given that the number of continents are too few for statistical analysis. This article provides a test of one observable implication of this thesis, namely that linguistic diversity should be more persistent to the degree that a geographic area is oriented more north-south than east-west. Using both modern states and artificial geographic entities as the units of analysis, the results provide significant confirmation of the relationship between geographic orientation and cultural homogenization. Beyond providing empirical support for one observable implication of the continental axis theory, these results have important implications for understanding the roots of cultural diversity, which is an important determinant of economic growth, public goods provision, local violence, and social trust.

A gated version of the paper can be found here, and Zoë Corbyn has a good summary here.


* These categorizations, as I said, are overly pessimistic and should not be taken too seriously. Laitin has ideas and Diamond tests his theories. But they have different comparative advantages.

What Huntington Forgot

Earlier this week I complained on Twitter about having to read Huntington’s “Clash of Civilizations” for the umpteenth time when virtually every serious IR scholar knows he’s wrong. I really despise the “wrong but influential” line of argument, because it so often means that someone has been given influence in the literature for being both inflammatory and wrong, which is different than being wrong but influential on policy.

The gist of Huntington’s argument is that in the post-Cold War period civilization will increasingly become a salient referent for conflict. While I do not have time to pick apart this argument in full, it does rest largely on civilization as a cultural constant, as most of the civilizations he recognizes reach back at least 1,000 years. To see how this assumption can be misleading, see the map of world religions in 1895 below.

Huntington is known for being politically incorrect, but thankfully he did not use “heathen” as a category (yellow). This simple example is not definitive, but illustrates that the way in which civilizations are conceived has changed in century between the creation of this map and the appearance of Huntington’s article.