Thinking of the Urban as Natural

Image result for urban ecology

“Name everything you can think of that is alive.” This was the prompt given to three different groups of children: the Wichi, an indigenous tribe in the Gran Chaco forest, and rural and urban Spanish-speakers in Argentina. It might not surprise you to know that the indigenous children who directly interact with wildlife often named the most plants and animals that lived nearby and were native to the region, and they often gave very specific names. The rural children named a mixture of both native Argentinian wildlife and animals associated with farming. But the urban children were very different from the others. They would name only a few animals in Argentina. Instead, they named significantly more “exotic” animals from forests and jungles in other countries and continents. This result has been replicated in multiple studies on child development. But we shouldn’t be so hard on the urban children.

This reflects a somewhat uncomfortable truth about how we learn. If you live in a city, you mainly learn about nature indirectly, through pop culture and formal science education. In both contexts, it is much easier to find information about “exotic” animals like lions or tigers instead of most of the organisms that make a home in the city. I think this is a symptom of a deeper cultural notion: that somehow cities are “fake” environments divorced from nature. I will argue that this distinction between the urban and natural is not only wrong, but also harmful to our society.

First, we should consider that this notion really only makes sense relatively recently in history. Cities are young in a geological and even anthropological sense, but since we’ve been making them as a species, they have been influenced by nature. We talk about “cradles of civilization” because they were places where the natural environment was well-suited to supporting early, complex social systems and their infrastructure. To use the literal Ur-example, consider the Fertile Crescent region, the convergence of the Tigris and Euphrates rivers. This provided lush soil at several elevations, which supported the growth of a variety of crops and helped with irrigation. And many modern cities can still be traced back to earlier environmental decisions. I am from Louisville, a city by a part of the Ohio River that could not be crossed by boat until the building of locks in the 1830s. The city was founded as a natural stopping point for people before they would go on to the Mississippi River.

Second, it seems incredibly alienating to argue most of humanity is “unnatural”. Since 2008, the majority of humans have lived in cities. By 2050, 70% of the global population will live in urban areas. We should not discourage the growth of cities or devalue them, when their more efficient use of resources and infrastructure is necessary to keep projected population growth sustainable. The smart development of cities recognizes they can help preserve other environments.

Finally, this urban-natural distinction distorts our understanding of the environmental and ecological processes that affect cities and even our broader understanding of the environment. A recent study showed that insects help reduce food waste just as much as rodents in New York City – for every memeable “pizza rat” there’s an army of “pizza ants” getting rid of rotting food. Despite their importance, in New York’s American Museum of Natural History renowned insect collection, they have almost no species native to the city. And since many city-dwellers like the Argentinian children only know about exotic species, it affects animal conservation efforts. Well-known “charismatic” species like pandas or rhinos have support all over the world. Few people are aware of endangered species in urban areas And sometimes scientists don’t even know. For instance, relating to the above, 40% of insect species are endangered, but we don’t know if that number is different in cities.

Instead of rejecting the last few thousand years of our society’s development, we should (re)embrace cities as part of the broader natural world. Recognizing that cities can have their own rich ecological and environmental interactions can help us build urban spaces that are better for us humans, other city-dwelling creatures, and the rest of the world.

(Note: This post is based on a speech I gave as part of a contest at UVA, the Moomaw Oratorical Contest. And this year I won!)


There Might be Life in Space, but This Paper Didn’t Prove It

An article published in the Journal of Cosmology last month made headlines with its bold claim: alien life can be found in Earth’s atmosphere. The rest of the scientific community ins’t convinced. The Journal of Cosmology isn’t a “peer reviewed” journal, which is the gold standard for scientific work. This means papers the journal publishes aren’t really evaluated for quality or accuracy. In fact, it’s even been labelled “predatory” by one research librarian. As a general rule, it’s also really not a good sign when a paper making a bold claim mainly cites other papers by its authors.

The lack of peer review on the paper seems justified; there’s not much data.  The paper relies almost entirely on just microscope images . Virtually any structure that has a bend or fiber is declared evidence of life, for no clear reason. (This may be a trend, as PZ Myers basically made the same complaint of a previous Journal of Cosmology paper claiming to have found bacteria in meteorites)

If you can see four bacteria in this post, I will give you a prize*

If you can see four living things in this post, I will give you a prize*

This paper claims the images are of diatoms or diatom-like lifeforms, but they don’t show any as reference and their images aren’t magnified like most that try to show diatom structures.

A known diatom from Earth.

The authors also try really hard to link the alleged cells they see to alleged organisms responsible for the red rains in Kerala, India several years ago (those claims inspired similar controversy and seemed to rely on evidence that was only slightly more firm than what is offered here). If you’re going to make that connection, though, maybe you should show an image of that.

Aside from images, the only other data the paper mentions is a technique to measure the amount of elements in the sample. The paper only says the samples are high in carbon and oxygen, but don’t provide numbers.  They say that means what they’re looking at isn’t a mineral, but it’s worth pointing out there are in fact many meteoroids that are mostly carbon and oxygen so they might be looking at weird dust from those. That’s it; no attempt to extract any potential organic matter (though that’s also a dime a dozen in space, even without life).

The people at the Journal of Cosmology say other scientists are irrationally opposed to the idea that life on Earth may have originally come from outer space. While that’s not the dominant opinion in biology right now, it actually is something mainstream scientists are looking at. It’s just that, as Carl Sagan said, “extraordinary claims require extraordinary evidence”. And a bad SEM image is not the latter.

*The prize is my affection.

Maybe They Could Bottle It

The Atlantic, once again, proves to be a source of weird and wonderful science stories.  And I am learning I love Rebecca Rosen’s reporting/blogging significantly more than Alexis Madrigal. The LA Times interview goes into a bit more detail. Dr. Barbara Lollar and her group from the University of Toronto found water trapped underground in a copper mine in Ontario that has basically been isolated from the rest of the Earth for at least a billion years. And it’s gotten kind of… ripe after being stuck in dissolvable minerals after all this time. Lollar describes it as having “the consistency of a very light maple syrup”. And it has so many minerals dissolved in it that contact with air starts to turn the water orange.

And yet that still seems less weird than this new water at Harris Teeter

And yet that still seems less weird than this new water at Harris Teeter

Evidently it is also very salty. There’s no numbers listed for that. Lollar just mentioned that she tasted it and said it was the saltiest water she ever tried. Yeah, so evidently she not only drank a sample of this, but she semi-regularly drinks other ancient water samples to get a feel for the mineral content. But she won’t let her students sample the most vintage H2O ever. What amuses me most is that Lollar and others say the water could support life and yet she still drinks it. This just sounds like the set-up of a terrible sci-fi B movie about an ancient microbe infecting a person in the present to take over Earth in the present.*

*Yes, I know, the odds of a 1 billion year old microbe being able to infect a modern human after their environments are  separated and they evolve separately are slim. But we do still have instances of invasive species being able to thrive in environments they weren’t native to. And it seems slightly more likely that a billion year old microbe will find something it could attack in a eukaryotic cell, since eukaryotes (the giant group of organisms with cells that have nuclei and organelles that includes plants, animals, and fungi) have been around for an estimated 1.6 billion years, than the few hundred million year old mammalian immune system having any idea how to respond to that.

When Your Home Starts to Dissolve You

Last weekmonth, a new study was published looking at ocean acidification, a (I think under-publicized) side effect of increasing CO2 concentrations.  A decent summary can be found at The Atlantic (in their health section, of all places).  The researchers (from a wide array of institutions in the US and Europe) focused on Arctic sea snails.  While that may sound incredibly boring, there are two main reasons they’re important to study.  First, their shells are calcium carbonate, which you’re probably more familiar with as limestone (or perhaps as the active ingredient in most over-the-counter heartburn medications).  Calcium carbonate makes up the shells of a lot of sea creatures.

Via The Atlantic

Happy snail

Via The Atlantic

Sad snail

And while we mention antacids, let’s bring up their counterpart, acids.  So carbon dioxide naturally dissolves in water to form a somewhat weak acid (you also see this idea come up with discussions of soda sometime – the CO2 from carbonation also dissolves in the soda and makes it acidic).  Although that’s a slight simplification because it actually turns out sea water is slightly basic (think the opposite of acidic) and has a pH somewhere around 8.15 , presumably because of the several thousand minerals that are dissolved from the coasts.  So if the ocean’s slightly basic, we’re fine, right?  Well, the term “acidification” is still accurate because the pH is lower (i.e. more acidic) than it used to be.  The process of sea creatures building up the calcium carbonate structures is sensitive to environmental conditions.  The carbonate dissolves more in solution with more carbon dioxide and/or lower pH (more acidic).  While that may initially sound like a good thing for any critters needing it (there’s more calcium carbonate in the water, right?), chemical equilibrium is a two way street; if it’s easier for something to dissolve, it’s harder to precipitate it back into a solid that might go into a shell.  Studies have shown that coral grows slower in acidic water because of this.

So what made this study important?  It looked at how acidification affects marine snails (also known more whimsically as “sea butterflies”) in the Antarctic, which are a very important part of the food chain (some marine biologists call them “potato chips of the oceans”).  The snails already showed significant signs of their shells dissolving.  While this isn’t a death sentence, it does make it easier for them to be eaten or catch diseases, and en masse, that could throw off population.

Of course, it’s important to note the researchers say the blame isn’t all on ocean acidification.  Part of the reason the seawater was so acidic was because of upswelling, an phenomena in which deeper water is pushed up to the ocean surface.  Deeper water tends to be more acidic (I can’t find why), so these upswells make the surface water abnormally acidic.  But upswelling is expected to increase with climate change.