Humans Made Conchs Shrink (And One Kid Saw It Coming)

The classic, swirling shell of a conch helps protect it from hungry birds and sea creatures, but when a human decides to pluck one from shallow water and boil it for supper, there’s not much the animal can do. Its only defense is to evolve, as a species, to be smaller and less appealing to people. That’s what conchs in the Caribbean have done—today’s humans get 40 percent less food out of a conch than our ancestors did. But that’s not so surprising to a 12-year-old girl who described almost the same thing in a piece of fiction.

To explain the fictional version, I have to insert myself into this story—hello! In my day job I edit a kids’ science magazine called Muse. We recently ran a contest that asked readers to write a brief, made-up story in the style of the magazine’s science news page. (The results were sometimes hilarious. “Too Much Coffee Makes Adults Feel Young” was an office favorite.)

One winner of this contest was a 12-year-old named Madeline. Her submission was about a new species, the “broken-shelled hermit snail” (Mendacious latibulum), discovered on the beaches of North America. It had gone undetected until now, the story went, by evolving a mangled-looking shell that kept human collectors away.

“She is almost certainly right in theory,” says Aaron O’Dea, a marine historical ecologist and paleobiologist at the Smithsonian Tropical Research Institute in Panama. As long as the mollusk were still alive while on the beach and vulnerable to collection, evolving an ugly shell could help it survive. O’Dea knows all about mollusks evolving to avoid humans; he recently discovered that the West Indian fighting conch (Strombus pugilis) has done exactly that.

O’Dea and his coauthors studied conchs living on the Caribbean side of Panama. To see how the animals had changed over time, they gathered shells from three general time periods.

The first was modern shells, which they collected by snorkeling, visiting tourist shops where the shells are sold as souvenirs, and sampling trash piles left by locals who eat the animals. (People sometimes denied gathering conchs for food, even when heaps of shells under their homes told a different story. The authors explain that there’s a regional stigma around eating the conch, nicknamed el raton del mar or “the sea mouse.” In Brazil, though, it’s sold as an aphrodisiac. Earmuffs, Madeline.)

Prehistoric conch shells, from humans’ earlier days living in the region, came from an archaeological site with material dating from around 690 to 1410 AD. In these days humans probably hunted the conch as they do today, wading into the shallows whenever they needed some for dinner. Finally the authors looked at local fossils, about 7,000 years old, to see conchs that had never met a human.

The researchers measured the length and width of the shells, as well as the thickness of each shell’s “lip,” the part overhanging the opening. O’Dea explains that this reveals whether a conch is a juvenile or an adult. When they’re young, conchs hide under the sand, slowly growing the spiky whorls of their shells. When they’ve stopped growing and are ready to emerge and find a mate, conchs develop the final portion of their shell, a thickened lip that makes it harder for predators to get inside.

By measuring the lip thickness of each shell, the scientists could tell whether a conch was mature. They found that over time, conchs have grown smaller and begun reaching maturity at a smaller size. The shells shrank between the 7,000-year-old fossils and the 1,500-year-old archaeological samples, and again between the archaeological samples and today. For as long as humans have been gathering conch, we’ve been driving their evolution.

“I had seen the conch in the field and noticed size differences,” O’Dea says, “but when I put it together empirically it was astounding!” Using each shell’s dimensions to estimate the size of the animal inside, he found that ancient conchs contained a “truly impressive” two-thirds more meat than modern ones. Today’s humans need more animals to make a meal than their ancestors did.

Conch sizes varied somewhat among the five modern areas the researchers sampled. The smallest mature shells came from a reef surrounded by homes with shell piles. Another group of small conchs came from a site that sells many shells to tourists. The largest conchs lived in a lagoon where no one is known to eat them. Other larger shells were found at a site surrounded by humans who prefer farmed meat to shellfish, and another site that’s been protected in recent years by scientists.

This shows that the conchs may be able to bounce back in size when people hunt them less. Still, none of these populations was as large as the ancient conchs. O’Dea says it’s not clear whether shrinking has hurt the species as a whole. Conchs may have initially evolved to be large, he speculates, because it helps them win fights for mates. He hopes to find the answer by comparing the fitness of larger and smaller conchs.

O’Dea says that Madeline’s broken-shelled snail story may be coming true in other ways. For example, “There is evidence that the desire for big, impressive antlers for trophies by deer hunters has led to the evolution of less impressive, or less ‘beautiful,’ antlers,” he says. “This is exactly what this girl is talking about, and I wouldn’t be surprised if we start to see fish or anything else that is selected against by humans for a certain trait follow suit.”

I tracked down Madeline herself to tell her the story of the fighting conch. She wrote back to say, “It’s really cool that something similar to what I thought might be plausible as an adaptation really works.”

Madeline says it’s funny that humans can alter the evolution of a whole species without knowing it. But given how easily we reshaped the conch, she’s more concerned about how many other, still-unseen effects we’re having on the world. Focusing on the single example of the conch while ignoring the rest, she says, “would be making a mountain out of a mole-usk hill.”

Image: by Loren Sztajer (via Flickr)

O’Dea, A., Shaffer, M., Doughty, D., Wake, T., & Rodriguez, F. (2014). Evidence of size-selective evolution in the fighting conch from prehistoric subsistence harvesting Proceedings of the Royal Society B: Biological Sciences, 281 (1782), 20140159-20140159 DOI: 10.1098/rspb.2014.0159

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About that Popular Guardian Story on the Collapse of Industrial Civilization

The end of the world, like everything worth knowing these days, will be tweeted:

NASA-funded study: industrial civilisation headed for ‘irreversible collapse’? | Nafeez Ahmed http://t.co/nWqOcD3UkB

— Guardian Environment (@guardianeco) March 14, 2014

If a study with the imprimatur of a major U.S. government agency thinks civilization may soon be destined to fall apart, I want to know more about that.

Click.

The piece cuts to the chase in the opener:

A new study sponsored by Nasa’s Goddard Space Flight Center has highlighted the prospect that global industrial civilization could collapse in coming decades due to unsustainable resource exploitation and increasingly unequal wealth distribution.

What follows is a straightforward summary of the paper, which the Guardian writer tells us has been accepted for publication in a peer reviewed journal called Ecological Economics.

I’m going to discuss the actual paper separately in the second part of this post. First, let’s talk about the Guardian write-up, its author, and how his piece went global, the latter of which is a sad commentary on journalism today.

Technically, the story appears on a blog in the environment section of the Guardian. The blog’s host is Nafeez Ahmed, who in his Guardian bio describes himself as “a bestselling author, investigative journalist and international security scholar.”

Since joining the Guardian’s blogging network in 2013, Ahmed has carved out what I would call the doomsday beat. He highlights individuals and academic papers that reinforce the thesis of his 2011 documentary, “The Crisis of Civilization,” which is about

how global crises like ecological disaster, financial meltdown, dwindling oil reserves, terrorism and food shortages are converging symptoms of a single, failed global system.

In a post last year, I briefly mentioned him, saying, “If you want a tour guide to the apocalypse, Ahmed is your guy.” Understandably, he didn’t appreciate this backhanded compliment.

In fairness to him, there is a seemingly never-ending supply of journal papers with apocalyptic themes to choose from.

A good example, of course, is the collapse paper he disingenuously hyped as being “NASA-sponsored.” (You’ll soon understand why that was deceptive.) Evidently, Ahmed  was shown the paper by its authors ahead of publication, which he turned into an article/post with this headline:

Nasa-funded study: Industrial civilization headed for ‘irreversible collapse’?

Ahmed thinks of himself as a journalist, so he writes many of his blog posts in a superficial news story format. He even refers to some of his posts as “exclusives,” which is how he characterized his write-up on the supposedly funded NASA study. Journalistic gloss, however, doesn’t mask fundamental journalistic shortcomings.

In the collapse paper Ahmed wrote about last week, he explains how the authors came to their conclusions, sprinkling in quotes from the paper. But he provides no reaction to the study from independent experts. If he questioned the three co-authors themselves, you wouldn’t know, since they are not quoted in his piece. To Ahmed, getting an exclusive apparently means not having to do any actual reporting.

On twitter, Ahmed was challenged to respond to rebuttals of the study he uncritically accepted. He demurred: “I’m just the reporter- ask the study authors.”

Chew on that for a second.

Ahmed’s summary of the soon-to-be published Ecological Economics paper at his Guardian blog–which he thought of as a big scoop–wouldn’t pass Journalism 101. Nonetheless, it was picked up by many other outlets around the world and became a sensation on social media. He was thrilled:

My NASA study exclusive has not just gone viral, it’s gone global and is making headlines in national newspapers all over

— Nafeez Ahmed (@NafeezAhmed) March 17, 2014

Naturally, the Daily Mail jumped all over it, as did the New York Post, which headlined its piece, “NASA Predicts the End of Western Civilization.”

Other headlines included: The National Journal: “Here’s How NASA Thinks Society Will Collapse”; The Times of India: “NASA-Funded Study Warns of Collapse of Civilization in Coming Decades”; and Popular Science: “NASA-Sponsored Study Warns of Possible Collapse of Civilization.”

Do you notice anything familiar about those headlines? NASA did and was pretty steamed. It recently issued a statement saying that the collapse paper

was not solicited, directed or reviewed by NASA. It is an independent study by the university researchers utilizing research tools developed for a separate NASA activity. As is the case with all independent research, the views and conclusions in the paper are those of the authors alone. NASA does not endorse the paper or its conclusions.

So much for the sexy NASA angle that was undoubtedly a big selling point. Not that it matters anymore. The marginal NASA connection was played up and successfully dangled as click bait. Mission Accomplished, Guardian editors and Ahmed.

So what else fell through the cracks on this story? Well, if you bother to read through all the herd-like media coverage of the study, you’ll notice that every piece essentially duplicates what the Guardian published. As far as I can tell, all the other similarly sensationalist articles did was reproduce or restate what appeared in the Guardian. And we know how much reporting went into that big exclusive!

Nobody from these other outlets talked to the study’s authors or solicited opinion from independent experts. Everyone willingly ceded the story to the Guardian. After teasing its readers with a few excerpts, PopSci gushed:

You should really head over to the Guardian for the full story; it’s worth reading.

This was not an isolated sentiment. Many people retweeted the story, including journalists in my twitter feed. There were a couple of skeptical outliers, some folks who know about mathematical models and were incredulous after reading both the study and the Guardian story. One is Robert Wilson, a UK Mathematical Ecology PhD Student who wrote up his impressions at his personal blog. Another is the U.S. science journalist David Appell, who offered his thoughts on the study’s model and (like Wilson) also took note of Ahmed’s conspiracy theorist leanings.

The huge, uncritical pick-up of the Guardian story perturbed me. Why was everyone so quick and seemingly content to parrot a story that contained no actual reporting? After all, it was just a blogger’s interpretive summary of an unpublished journal paper. Why didn’t anyone reach out to the paper’s authors or bother to call a few sources to examine the merits of the study?

So I thought I’d fill that journalistic vacuum myself. In part two of this post, I’ll report what the authors of the paper had to say after I contacted them, and what numerous, highly regarded experts think of their study. This is completed. I’m just proofing the material and breaking it out into a separate post.

Check back in several hours for part two.

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Satellite Images Show Floating Objects in Indian Ocean

Satellite images released by the Australian government show possible objects floating in the Indian Ocean that could be wreckage from Malaysian Airlines flight 370. The images are of the same object. One is panchromatic, meaning it is based on all wavelengths of light falling on each pixel. The other is multispectral, meaning it is based on specific wavelengths. (Source: Australian Maritime Safety Authority)

Could floating objects seen in satellite images of the Indian Ocean off the coast of Australia be wreckage from the missing Malaysian Airlines jet that disappeared on March 8?

The Australian government thought the satellite images above, and another pair lower down in this post, warranted a search by aircraft. But the first try has turned up nothing — because of limited visibility due to clouds and rain, as this Tweet from the Australian Maritime Safety Authority states:

RAAF P3 crew unable to locate debris. Cloud & rain limited visbility. Further aircraft to continue search for #MH370

— AMSA News (@AMSA_News) March 20, 2014

Here’s a map of the area in the Indian Ocean that was searched by the Australians today:

Source: Australian Maritime Safety Authority

And here’s what that area of the Indian Ocean looked like to NASA’s Aqua satellite today:

Extensive cloudiness obscures parts of the Indian Ocean off the west coast of Australia, as seen in this image based on data from NASA’s Aqua satellite. (Source: NASA)

To my eye it appears that the area being searched is underneath that big patch of cloudiness seen this image. Let’s hope it clears.

Lastly, another pair of images showing another a second possible object:

Source: Australian Maritime Safety Authority

As more remote sensing and other kinds of imagery come in, I’ll post them here at ImaGeo. So stay tuned.

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The March of Climate Determinism

In the late 2000s, a new climate change story line emerged in the media.

The seeds for this narrative were perhaps sown ten years ago, when a worst-case scenario report commissioned by the Pentagon triggered breathless headlines about a research field known as “abrupt climate change.” Perhaps you saw the 2004 movie.

The sensationalist portrayal of a sudden climate-induced doomsday was dismissed in scientific circles as implausible, but the film caught people’s attention.

What followed was a more sober analysis from Beltway think tanks assessing the linkages between climate change and geopolitical strife. Congress held hearings on the climate/national security nexus and the issue –while politically contentious–was taken seriously in the U.S. military and intelligence communities. Indeed, climate change was projected to be a major driver of future conflicts and instability around the world.

I wrote about this emerging issue on numerous occasions in the late 2000s, including in this space. (Here’s a more recent round-up of high profile studies.)

In the last several years, some scholars and influential pundits have argued that global warming played a major role in the Arab Spring. The notion that climate change sparked Syria’s hellish civil war has also gained currency in some circles.

When we get to this point–when famines and wars with deeply rooted socio-political causes–are attributed to climate change–we are approaching the same territory inhabited by those who routinely cast every severe weather event and catastrophe in the context of climate change. (This unfortunate tendency is rued by some in the climate community.)

Researchers who study the environment/security intersection–and who strive to remain unbiased–know that the climate change-security discourse has taken a problematic direction. (Indeed, some warned about it.) At the Woodrow Wilson Center’s Environmental Change and Security program, read this new post by Francois Gemenne, who writes:

Debate on the human security dimensions of climate change has often been cast from a deterministic perspective, where global warming will automatically translate into mass migrations, competition for resources and land, and ultimately conflict and devastation. There are two problems with this rhetoric.

To understand those problems, read the whole commentary. And when you’re done, check out this 2007 piece by Mike Hulme, who also warned about the seduction of climate determinism.

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White House Launches Climate Change Communication Tool that Treats Citizens Like Adults

Screenshot of an interactive map accessible from data.gov/climate showing expected inundation of areas of New York City based on different projections of sea level. (Source: NOAA and data.gov/climate)

A day after a major scientific organization released an embarrassingly ineffective report aimed at communicating the realities of climate change, the White House has launched something entirely different — and better.

For now, it is a web portal that serves as a kind of clearinghouse for all manner of information on how sea level rise is remaking our coasts and posing risks to those who live and work along them.

The screenshot above shows one of the interactive tools available on the site, data.gov/climate. In stunning graphic detail, it shows areas in the New York metro area that would become inundated in the future based on different projections of sea level rise. It’s one of just dozens of such tools available right now on the site.

And according to the White House, it is just the start of a major effort at climate change communication. The effort is designed to enable citizens to see how climate change is affecting them where they live and work, and what they might expect in the future, through interactive, graphics-based digital tools.

Yesterday’s report by the American Association for the Advancement of Science was, at its heart, a “We’re scientists, so listen to what we say” effort. In contrast, the initiative launched by the White House today treats people like grownups and gives them powerful tools to learn for themselves what’s happening. And unlike the AAAS report, its ultimate goal is to take full advantage of the power of digital technology — and visual communication — to empower people to plan for a future of climate change.

I’ve only had time to scratch the surface of the new web site. But so far, I’m impressed. And I know that it will be helpful in my future reporting on climate change.

To offer just one example, the web site offers access to an online, interactive tool from the National Oceanic and Atmospheric Administration that allows users to select a county and get a quick snapshot of its demographics, infrastructure and environment within flood zones. The results include a floodplain map, and graphics showing the overall population in floodplains, as well as the population over 65 years of age and in poverty that live in these areas, along with a plethora of other useful statistics and information.

I’ll be poking around the new site in coming days, and I may come back with an update on what I find.

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Giant "Chicken From Hell" is New Dinosaur Species

The big, bad, beaked stuff of nightmares, new dinosaur Anzu wyliei is described as “hell’s chicken” by the researchers who found it. Credit: Mark A. Klingler, Carnegie Museum of Natural History.

Researchers announcing a newly described dinosaur called it the “chicken from hell,” “hell’s chicken” and “scary as well as absurd.”

More prosaically known as Anzu wyliei, the beaked dinosaur stood about ten feet tall and more than 11 feet long with a tall crest on its head and sharp claws. A. wyliei lived about 66 million years ago in what’s now North and South Dakota, possibly sharing the same habitat as the iconic Tyrannosaurus rex and Triceratops species. Researchers announced the new species this week.

Despite its vicious-looking claws, A. wyliei likely ate vegetation, small animals and possibly the eggs of other species. It lived on a floodplain and, while flightless, had a bird-like appearance with slender legs and a toothless jaw. Although no fossilized evidence of feathers were found, based on its relationship with other feathered species, researchers believe the animal had feathers on its tail and arms.

Illustration courtesy of Bob Walters.

Researchers estimate Anzu wyliei weighed perhaps 450-650 pounds, making it among the largest known oviraptorosaurs.

Oviraptorosaurs are feathered dinosaurs that belonged to the larger maniraptor group, from which modern birds evolved.

Aside from getting to put the phrase “chicken from hell” in a press release, researchers who described the new dinosaur today in the open-access journal PLoS One have good reason to be excited about the find. Their analysis is based on partial remains of three separate individuals found in the Hell’s Creek formation; together, the fossils form an almost complete A. wyliei skeleton. That’s important because the dinosaur belongs to the Caenagnathidae family, a mysterious offshoot of the oviraptorosauria subgroup previously known only from a handful of fragmentary bones.

Having a nearly-complete example of a Caenaghathid not only fills in a blank in the fossil record, it’s also rewriting the oviraptor family tree.

Already A. wyliei‘s remains have settled a debate about the relationship between different oviraptors species: “hell’s chicken” has shown North American oviraptors are much more closely related to each other than to similar species in Asia. At the same time, researchers believe an Asian oviraptor, the 26-foot-long Gigantoraptor, should be reclassified as a Caenaghathid based on similarities its shares with A. wyliei.

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Explore the Milky Way in Amazing 360-Degree Panorama

The Cat’s Paw Nebula. Credit: NASA/ESO/DSS2

Do you lack the time and funds for a fancy spring break getaway to some tropical clime? Well, NASA has the perfect intergalactic trip package for you. From the comforts of your desk chair, you can venture thousands upon thousands of light years into the Milky Way galaxy and return before your lunch break is over.

NASA’s Spitzer telescope spent the past decade snapping two million infrared photographs of our galaxy to stitch together a massive 360-degree panorama of the Milky Way. It’s the most detailed infrared panorama of our home galaxy ever made, and was derived from the GLIMPSE360 project.

Our galaxy is a flat, spiral disk about 100,000 light years in diameter. The GLIMPSE panorama only includes a small sliver of the sky — about 3 percent — but includes more than half of the stars in the Milky Way, which is due to our galaxy’s pancake shape.

When you take time to explore the panorama, you can find distant galaxies and areas of star formation. You’ll also notice that our galaxy is riddled with bubbles. These structures are cavities around massive stars, which blast wind and radiation into their surroundings. GLIMPSE also added navigation shortcuts so you can skip to popular destinations like Cat’s Paw Nebula, Canis Major and the galactic center (where a massive black hole resides).

However, the GLIMPSE data aren’t all for show. The data have helped astronomers create precise star maps of the Milky Way’s inner arms. The data will also guide NASA’s upcoming James Webb Space Telescope to areas of star formation, where it will make even more detailed observations. The GLIMPSE panorama and Spitzer telescope mission are described in more detail in the video below.

While your friends and coworkers may tout their newly bronzed skin, you can brag about your tromp through the dark, unexplored backcountry of our galaxy where some of the faintest stars exist. Subsequently, your friends and family may suggest you take an actual vacation.

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