Up close, from above:
Arabis alpina subsp. caucasica
Portland-based science writer
Up close, from above:
Arabis alpina subsp. caucasica
Nobody lives here: The nearly 5 million Census Blocks with zero population
A Block is the smallest area unit used by the U.S. Census Bureau for tabulating statistics. As of the 2010 census, the United States consists of 11,078,300 Census Blocks. Of them, 4,871,270 blocks totaling 4.61 million square kilometers were reported to have no population living inside them. Despite having a population of more than 310 million people, 47 percent of the USA remains unoccupied.
Green shading indicates unoccupied Census Blocks. A single inhabitant is enough to omit a block from shading
Quick update: If you’re the kind of map lover who cares about cartographic accuracy, check out the new version which fixes the Gulf of California. If you save this map for your own projects, please use this one instead.
The map tends to highlight two types of areas:
- places where human habitation is physically restrictive or impossible, and
- places where human habitation is prohibited by social or legal convention.
Water features such lakes, rivers, swamps and floodplains are revealed as places where it is hard for people to live. In addition, the mountains and deserts of the West, with their hostility to human survival, remain largely void of permanent population.
Of the places where settlement is prohibited, the most apparent are wilderness protection and recreational areas (such as national and state parks) and military bases. At the national and regional scales, these places appear as large green tracts surrounded by otherwise populated countryside.
At the local level, city and county parks emerge in contrast to their developed urban and suburban surroundings. At this scale, even major roads such as highways and interstates stretch like ribbons across the landscape.
Commercial and industrial areas are also likely to be green on this map. The local shopping mall, an office park, a warehouse district or a factory may have their own Census Blocks. But if people don’t live there, they will be considered “uninhabited”. So it should be noted that just because a block is unoccupied, that does not mean it is undeveloped.
Perhaps the two most notable anomalies on the map occur in Maine and the Dakotas. Northern Maine is conspicuously uninhabited. Despite being one of the earliest regions in North America to be settled by Europeans, the population there remains so low that large portions of the state’s interior have yet to be politically organized.
In the Dakotas, the border between North and South appears to be unexpectedly stark. Geographic phenomena typically do not respect artificial human boundaries. Throughout the rest of the map, state lines are often difficult to distinguish. But in the Dakotas, northern South Dakota is quite distinct from southern North Dakota. This is especially surprising considering that the county-level population density on both sides of the border is about the same at less than 10 people per square mile.
Finally, the differences between the eastern and western halves of the contiguous 48 states are particularly stark to me. In the east, with its larger population, unpopulated places are more likely to stand out on the map. In the west, the opposite is true. There, population centers stand out against the wilderness.
Ultimately, I made this map to show a different side of the United States. Human geographers spend so much time thinking about where people are. I thought I might bring some new insight by showing where they are not, adding contrast and context to the typical displays of the country’s population geography.
I’m sure I’ve all but scratched the surface of insight available from examining this map. There’s a lot of data here. What trends and patterns do you see?
- The Gulf of California is missing from this version. I guess it got filled in while doing touch ups. Oops. There’s a link to a corrected map at the top of the post.
- Some islands may be missing if they were not a part of the waterbody data sets I used.
Creative Commons Attribution-NonCommercial-ShareAlike
Block geography and population data from U.S. Census Bureau
Water body geography from National Hydrology Dataset and Natural Earth
Made with Tilemill
USGS National Atlas Equal Area Projection
Skulls made of toy soldiers and flowers
Female penis, male vagina
The females of the cave-dwelling insect Neotrogla aurora penetrate the males with a penis-like organ. It’s inflatable and covered in spines that prevent males from escaping during copulations that last 40 to 70 hours. (When researchers tried to separate one copulating pair, they ripped the male in half while the genitals remained interlocked.) Competition among females for nutritious “seminal gifts” may have driven the evolution of the female penis:
All known Neotrogla species inhabit extremely dry oligotrophic caves and feed on bat guano and bat carcasses, which are relatively scarce resources. Under such circumstances, nutritious seminal gifts cause a strong selection pressure for increased female mating rate.
Source: Female penis, male vagina, and their correlated evolution in a cave insect by Kazunori Yoshizawa, Rodrigo Ferreira & others, Current Biology (2014)
“Using little more than a flattened fossil, researchers from UC Berkeley have created a stunningly life-like computer rendering of a long-extinct lycopod. A quick glance at this primordial plant reveals a very alien-looking species.
The computer rendering was compiled by graduate student Jeff Benca.”
Learn more at io9.
When they were built in the 1970s these two gleaming Ohio malls were symbols of the boom years in the U.S., and their wide walkways were filled with shoppers.
Now the verdant foliage that decorated them has died off and the fountains inside are dry as store after store deserted the out-of-town malls.
The demise of the Rolling Acres and and Randall Park Mall have been documented by photographer Seph Lawless, who remembers visiting them when he was a child and even had his first job at one of the them.
When Rodents Were Rhino-Sized
The yellow curve shows the emergence of rhino-sized rodents in South America about 20 million years ago. It’s from a new paper linking the evolution of gigantic size in mammals to global changes in climate towards cooler and harsher conditions. [Patterns of maximum body size evolution in Cenozoic land mammals: eco-evolutionary processes and abiotic forcing by Juha Saarinen et al, Proceedings of the Royal Society B: Biological Sciences (2014)]
The superb painting by James Gurney shows Josephoartigasia monesi, an extinct rodent that weighed about 2,000 pounds, judging from fossil remains described in 2008. It is the largest of the 50 known species of Dinomyidae, a family of giant rodents from South America, all but one now extinct. The pakarana (Dinomys branickii), the only surviving family member, weighs in at around 30 pounds.
Explosive pods launch seeds up to 20ft
Speaking of the evolutionary strategies of seeds, let’s all take a moment and appreciate this fantastic “exploding pod” maneuver, employed by a number of plants. Some varieties of Caigua (which I discussed last week), have to be harvested with goggles, just in case they pop!