Monthly Archives: November 2013

What First Sparked Your Fascination with Science?

Sea anemone and clownfish.

Sea anemone, you were an awkward 12 year old’s biggest crush. Credit: Ashley Braun/All rights reserved.

When I was twelve years old, I had science class in the cinder-block basement of my middle school. But perched along the perimeter of that schoolroom filled with basic black lab tables and little natural light was a bubbling saltwater aquarium and a couple plastic containers with secure, vented lids.

We students, trustworthy sixth graders that we were, could volunteer to feed their inhabitants: sea anemones, a furry and secretive tarantula, and three-inch long Madagascar hissing cockroaches.

I savored the opportunity to stick my gangly arm deep into the saltwater tank, tickling the sea anemones’ sticky tentacles as I dropped bits of chicken onto the marine invertebrates’ smooth oral disks. For a young girl hundreds to thousands of miles from the ocean or tropical forests, these science class pets quickened my pulse and my fascination with the natural world. I didn’t care if it was the weird bugs in my classroom or the rhinos, three-toed horses, and camels buried by volcanic ash in northeastern Nebraska, which we ventured out to see while visiting my mom’s family. I find these experiences and my reactions to them (delight rather than horror or boredom) reassuring. Then again, I’m a professional science writer.

But these sparks of interest in science aren’t (and shouldn’t be) limited to those of us with a professional connection to science. Carpenters and professional football players and accountants and waitresses are welcome too.

One point made over and over again at the recent Evolving Culture of Science Engagement workshop was that we as science communicators need to figure out how to reach beyond the usual audiences of those already interested and light that spark of curiosity and critical thinking in everyone else. The aim? A scientifically literate public.

The world depends on informed citizens making informed decisions. Science and technology have become entwined in everyday life in unprecedented ways, and the average person should be able to understand enough about the world around them — or at least respect the scientific pursuit of understanding — to act appropriately when life and society require it.

Psychology professor Caleb Lack explores on his blog Great Plains Skeptic the question of what a scientifically literate population looks like in the 21st century. What resonated the most with me was his definition of scientific literacy not as a memorized collection of facts but more as a way of thinking:

Science is, instead, an empirical, rational way of thinking and seeking answers to questions and evaluating claims. It is the application of a specific series of steps to arrive at empirical support for or against an idea. As such, scientific literacy should not be seen as the ability to parrot answers to questions such as “What is the speed of light?” or knowing the steps used to balance a chemical equation. Scientific literacy should instead be seen as the ability to access and use the methods of science when confronted with a question to which one does not know the answer. It should be seen as the ability to minimize the myriad of thinking errors to which we humans are so prone while using those same methods. A scientifically literate society should be able to, in short, think like a scientist about its dilemmas by evaluating the world skeptically.

Yet people today can still believe that Earth is only 6,000 years and that the measles vaccine causes autism and other disorders despite repeated, rigorous scientific study discrediting these claims. Part of this discrepancy originates in humans’ tendency to rationalize preexisting but strongly held beliefs (often coming from their religion, community, or cultural leaders), even at high levels of education. But another factor is scientific illiteracy, the inability to think critically, be open to examining credible evidence, or distinguish between science and pseudoscience.

Approaching this challenge by trying to force-feed people ever-more facts discrediting their beliefs doesn’t work and can even backfire, instead reinforcing incorrect notions. Even in the face of spectacular refutation of their belief systems, people can still manage to believe aliens are coming to save them from the apocalypse.

So. How do we go from apocalyptic aliens to a societal respect, and perhaps hunger, for science?

A vital step is tailoring the communication of scientific information to the cultural values of the audience. But I also think we can find clues about what works in the conversation started on Twitter by Ben Lillie, physicist-turned-storyteller and founder of The Story Collider. He asked people about their early science-related inspirations — those books, people, moments, etc., that touched them in a very real way.

Right. Switching hashtags. What science thing first made you really *feel* something? #sciencespark

— Ben Lillie (@BenLillie) November 13, 2013

An overwhelming deluge of nostalgia and excitement followed (which you should read): people sharing memories of gaping wide-eyed at Saturn’s rings through a telescope, of being inspired by beloved or bizarre family members and teachers, and of amazing things like this:

.@BenLillie In daycare they told us about the Earth’s crust, so I took a shovel under a tree to find it. #sciencespark

— Elizabeth Preston (@InkfishEP) November 14, 2013

As children, these experiences of discovery, when everything is new and wondrous, are nearly effortless. But how do we as busy, cynical adults recapture that instinctive, unabashed curiosity about the universe and how things work, whether it’s wondering how the rain hits the windshield or what makes up the microscopic particles what make up everything? When do you remember having that spark of understanding mixed with an openness to exploring the infinite possibilities of the universe? When did you lose it (if you feel you did)?

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De Compostus: A Brief History of Putting Animal Poop on Plants

A relief of a Gallic-Roman harvesting machine.

A relief of a Gallic-Roman harvesting machine. Credit: Public Domain

“When the weather is bad and no other work can be done, clear out manure for the compost heap,” recommends Roman statesman Marcus Porcious Cato, better known as Cato the Elder. In his writings De Agricultura, he shares the secrets to running a successful farm-business in the ancient Roman Empire.

In this work, Cato, who lived between 234 and 149 B.C., provides us with an early how-to guide for enriching the soil through the practice of composting.

The Dirt on Dirt (and Compost)

Compost is not actually soil itself, but the dark, crumbly result of a controlled process of breaking down animal and vegetable matter. The resulting product is fairly stable, no longer decomposing at the previously speedy rate, and is full of nutrients (especially nitrogen and carbon) and minerals in forms ready for hungry plants to absorb.

Black gold: The earthy results of composting with worms.

Black gold: The earthy results of composting with worms. Credit: Red58bill, Creative Commons Attribution 3.0 Unported license.

But composting isn’t just any old rot, full of stink and muck. It involves humans maintaining roughly the right ratio of moisture, air, carbon, and nitrogen. It involves aerobic decomposition, which requires oxygen and is the main reason for occasionally “turning” or mixing a compost pile. It also involves microbes, fungi, insects, and worms all munching on and pooping out the delicious organic (carbon-based) goodness in a compost pile.

Composting for the Lazy and the Ancient Scots

A dedicated “compost pile” isn’t even necessary for this magic to happen. One of the many ways to compost is referred to as “sheet composting.” At the end of the growing season, you mix up a moist layer cake of nitrogen-heavy “green” materials (e.g., mowed grass, bolted lettuce plants, chicken manure) with carbon-heavy “brown” materials (e.g., chopped up woody plants, dead leaves, cardboard). You toss all of this right on top of a garden bed, cover it with some burlap sacks, and ignore it until spring, when you will find several inches of nutritious compost on top of the plot.

This method doesn’t sound all that different from some of the oldest practices of humans composting. Sometime in the Neolithic Age, roughly 7,000 years ago, when hunter-gatherers began making the switch to farming, they figured out that having manure and vegetable waste in the soil around their food plants was a great idea.

A 2005 British study published in the journal World Archaeology found evidence of farmers in what is now Scotland using their garbage piles of food scraps and manure (“midden heaps”) as garden beds:

“from the Neolithic to the Iron Age, midden heaps were sometimes ploughed in situ; this means that, rather than spreading midden material onto the fields, the early farmers simply ran an ard over their compost heaps and sowed the resulting plots.”

In addition to the Romans and Neolithic Scots, the ancient Chinese and Egyptians also had an appreciation for amending the soil.

When in Rome, Compost as the Romans Do

Cato the Elder, however, preferred burying manure and other compostable materials around the roots of olive trees and grape vines and letting it break down there.

“See that you have a large dunghill; save the manure carefully, and when you carry it out, clean it of foreign matter and break it up. Autumn is the time to haul it out. During the autumn also dig trenches around the olive trees and manure them.”

“In an old vineyard sow clover if the soil is lean (do not sow anything that will form a head), and around the roots apply manure, straw, grape dregs, or anything of the sort, to make it stronger.”

His techniques apparently went beyond these modern sustainable farming practices and strayed into what we might now call the “biodynamic” (“a spiritual-ethical-ecological approach” to farming that emphasizes the land as an interconnected, living organism and takes into account things like planting and fertilizing based on lunar cycles and burying in the soil at night a cow horn stuffed with cow dung).

Perhaps Rudolf Steiner, founder of the biodynamic farming movement, took his inspiration from Cato the Elder and his composting contemporaries in Rome:

“Divide your manure as follows … Save the last fourth for the meadows, and when most needed, as the west wind is blowing, haul it in the dark of the moon.”

Farmers, take note: a new moon is the best time to compost.

Not All Animal Poop Is for Plants

Cato gives excellent advice for improving the soil with a variety of manure sources, as well as a sort of olive oil-based “dressing” (amurca) to give crop trees a boost:

“Fertilizers for crops: Spread pigeon dung on meadow, garden, and field crops. Save carefully goat, sheep, cattle, and all other dung. Spread or pour amurca around trees, an amphora to the larger, an urn to the smaller, diluted with half its volume of water, after running a shallow trench around them.”

Pigeon, goat, sheep, cattle … all are good sources of manure for Ye Olde Compost Pile. But a question that often comes up for Ye Modern Urban Composter and Pet Owner is whether or not you should add dog or cat poop to your compost.

In short, no.

In long, because dog and cat feces are full of pathogens, or disease-causing microbes and parasites which humans should want nothing to do with. Many of these pathogens or their eggs or spores won’t be killed by the composting process and can stick around in the soil for a long time, in some cases, up to four years.

Dog poop in particular has been studied as a plentiful source of nasty microbes, being called a “reservoir,” even, for Escherichia coli (E. coli). Rural communities in Canada have been observed to have a high incidence of pathogens in dog feces, including Toxocara canis (roundworms), Echniococcus granulosus, Giardia duodenalis, Cryptosporidium spp., and Campylobacter spp. And let’s not forget Salmonella.

What do these pathogens do to people? All kinds of fun!

  • Diarrhea!
  • Cramping!
  • Nausea!
  • Skin sores!
  • Inflamed stomach lining/heart wall/lungs/kidneys!
  • And more!
Some like it hot: A compost pile with cow dung reaches 145 degrees Fahrenheit.

Some like it hot: A compost pile with cow dung reaches 145 degrees Fahrenheit. Credit: Fishermansdaughter, Creative Commons Attribution 2.0 Generic License

These are not the sorts of things you want to be putting on your tomatoes and lettuce.

Of course, livestock manure can have some pathogens too, such as E. coli and Salmonella. To kill these pathogens, the manure needs to be in a “hot” compost pile, where they are exposed to temperatures maintained at 140 degrees Fahrenheit for at least three days. It’s generally accepted that composting dog and cat feces would run a much greater risk to humans. So, don’t do it.

Instead, “doo” as the Romans do.

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Cooking: My Path to the Feast

My favorite cookbooks.

Some of my favorite sources of culinary inspiration: Simply in Season, Mark Bittman, Barbara Kingsolver, and my longtime community supported agriculture (CSA) program. Credit: Ashley Braun/All Rights Reserved

I’m not going to pretend that cooking is “easy.”

At this point in my life, I love it and I think that everyone should learn the basic culinary skills (chop, boil, saute, etc.) to feed themselves and their families healthy food. But I used to stumble through my meals, relying heavily and with blind faith on complicated, by-the-book recipes, balanced out by the most basic of quesadillas.

It’s not that my parents never introduced me to cooking growing up. They expected my three siblings and me to be able to make pork chops and cheese potatoes, hamburgers, mashed potatoes. The type of hearty Midwestern meals centered on meat and potatoes. But the secrets of seasonings–aromatic fresh herbs, exotic powdered spices–remained foreign to me. To the extent that I once “experimented” by adding something like nutmeg to canned spaghetti sauce, to the dismay of my waiting family. My parents informed me that I would be eating the leftovers.

Then, three things changed.

  1. After graduating from college, I moved to Seattle, a city I had never been to and have not since left. A city with a vibrant local food scene. Here, I lived with someone whose culinary prowess exceeded my own, who savored trips to local spice shops, who was willing to toss an occasional wild card into the proverbial stew pot. Who could feed five hungry roommates on a $10 dinner budget and who let me in on the joyful secrets of cooking.
  2. I stopped eating meat. Inspired by the talented writings of my then-colleague Tom Philpott and uninspired by the destructive policies of industrial agriculture and factory farming, I gave up meat for Lent. And the habit stuck. This sent me back to the drawing board to learn how to cook a meal without meat as the anchor. I got creative.
  3. I eventually subscribed to a community supported agriculture program, Tiny’s Organic. This third-generation family farm a couple hours away in central Washington inundated my fridge and shelves with pounds of fresh, flavorful fruits and vegetables every week for six months of the year. Here were delicious, diverse varieties of produce I had never tasted or even heard of, which piled up–and often rotted–quickly. This was an incentive to figure out what to do with feathery, pale green bulbs of fennel, a dozen velvety orange apriums, or an unidentified, warty winter squash.

It was a combination of these factors that led me to begin chopping, mixing, roasting, sauteing, and baking with new vigor. Now I was preparing food with a joy and flavor I hadn’t previously known or embraced.

I began listing kitchen utensils and cookbooks on gift wish lists. I was laboring in the kitchen over new recipes late into the night. I was growing my own food in containers outside my door, growing herbs like rosemary, basil, thyme, sage, oregano. Not only did I know how to tell them apart, but I knew when and how much to sprinkle into dishes. (Try thyme and a little olive oil on pan-fried peaches served over arugula. You’ll thank me later.)

Sweet potato and white bean chili. Vegetarian tested, carnivore approved.

Sweet potato and white bean chili. Vegetarian tested, carnivore approved. Credit: Ashley Braun/All rights reserved.

But I’m not going to pretend that this transformation was instantaneous (it wasn’t) or that it was always satisfying or successful (nope, neither of those). I’ve boiled over soups and jams, scorched sauces, sliced fingers (five stitches), and been dead on my feet, exhausted after a long day of work and several hours of cooking, with an expectant and miserably large pile of dishes to tend to after my tasty but too-few minutes of mealtime.

Still, I think it’s worth it. Everyone’s going to take a different path to feeding themselves, but I’m happy that mine has led to improvised sweet potato-white bean chili, juicy plum pie, and flaky rustic tart with kale, dandelion pesto, caramelized onions, and fresh tomatoes.

Everyone’s invited to the feast; let’s eat!

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Daylight Saving Time, Saving Energy, Saving Lives?

I don’t think I ever fully realized how fraught the concept of Daylight Saving Time was and what controversy surrounds “falling back” or “springing ahead” an hour.

Disorienting? Sure.

Annoying? Occasionally.

But life-threatening? Seems a touch dramatic.

Yet NPR highlighted a study finding an increase in violent street crime and robbery that occurs when we “lose” an hour of daylight in fall evenings. Apparently robbers like to sleep in as much as I do.

(But I doubt they’re aware of the price of that extra hour of shadowy mischief-making: they and everyone else also have an increased risk of heart attacks, traffic accidents, and injuries in the workplace on the Monday immediately following the end of Daylight Saving Time. Researchers tend to blame disruptions to sleep patterns for some of these effects.)

Economists Jennifer Doleac of the University of Virginia and and Nicholas Sanders of William and Mary took advantage of the Energy Policy Act of 2005 extending Daylight Saving Time (DST) by an extra three weeks in the spring and one week in the fall. They compared neighborhood crime rates during the switch to DST in spring and fall of 2005 and 2006, before the law took effect, and with the same time periods in 2007 and 2008. Their study [PDF] uncovered a 7% drop overall in robberies after DST takes effect, stealing an extra hour of darkness from the evenings when ne’er-do-wells would prefer to not do well and take your wallet under the cover of darkness.

So, Daylight Saving Time may save you from getting hit by a car and hit up by a robber, but does it live up to its perennial justification of saving energy?

Well, various reports conclude that … it depends.

If you live in Indiana, then it may slightly increase residential energy use [PDF]. (This state actually used to be split, with some counties observing DST and others never paying attention to a time change. Having lived there during that time, I can attest that was truly annoying.)

If you live in California, it may actually sorta save some energy (perhaps 0.93% of your daily energy bill [PDF]).

And if you live in all of the United States at the same time (I think that’s how national averages work), extending Daylight Saving Time cuts about 0.03% of annual U.S. electricity consumption [PDF], which is at least better than a coal-fired punch in the face.

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1996-2013: My Space Odessy

Constellation Cassiopeia in the night sky.

Ever since I was 12, I’ve been tight with Cassiopeia, the vain Ethiopian queen of Greek mythology who sits in an upside chair in the sky half the year. Credit: Till Credner, Creative Commons Attribution-Share Alike 3.0 Unported license.

When I was in sixth grade, my science teacher gave us an assignment: to record the phases of the moon every night for a month. So, fairly faithfully, I would head outside after nightfall into the cul-de-sac of my suburban Cincinnati home and painstakingly draw the moon’s fluid shape on a series of 3×5 index cards.

The idea was that we were creating miniature astronomy flipbooks that would show the time lapse of the moon waxing toward full and waning toward new. I called my little book, “Flipping the Moon,” complete with a cartoon Man-in-the-Moon doing gymnastics on the cover.

In addition to my lunar sketches, I was supposed to write down any additional observations of the night sky, but between the light pollution and my limited knowledge, I think my most common comments were about seeing the Big Dipper, Orion’s Belt, and Cassiopeia. Clearly, I was discovering the edges of the universe!

My Galaxy and Me

Another memorable moment in my early fascination with the worlds beyond my own was when I was on an overnight trip of some kind as a teenager and first discovered my own galaxy. The Milky Way was breathtaking. And I actually was at the edge of it. It felt so empowering to be able to recognize that creamy band of stars and planets stretching across the sky. Like when you learn a new word and suddenly you start hearing it everywhere–and understanding in a way you hadn’t before.

It’s something I carried with me as a college student spending a summer in the northwoods of Wisconsin, sitting in a small boat with two other students, taking samples of tiny drifting zooplankton at 2:30 a.m., staring at the perfect mirror the lake made of the stars and my galaxy when I looked up and when I looked down. All I could do was contemplate the universe and my place in it as we dropped the sampling equipment off the side of the boat into the dark waters below.

Space Does Weird Things to You

Since my early starry-eyed ruminations, however, my occasional forays into space as a “grown up” have taken a different turn. Ever since I read Mary Roach’s book Packing for Mars: The Curious Science of Life in the Void, when I now think about space, I almost can’t help but think about the bizarre things weightlessness does to the human body.

Here are a few of my favorite facts I learned about life that is out of this world:

  1. Without gravity, your normally heavy organs actually float inside your body, drifting up your ribcage and “reducing your waistline in a way no diet can.”
  2. You can’t tell when you have to urinate until your bladder is nearly full. In weightlessness, the urine spreads out around your bladder and not in its bottom, preventing you from feeling the usual “I’ve gotta go” pressure that comes with an expanding bladder.
  3. Early astronauts had to complete eye exams (posted on the space craft’s dashboard) constantly to confirm that weightlessness wasn’t changing the shape of their eyeballs to the point that they couldn’t see properly.

For more details about how outer space affects the few humans who make it there, check out an interactive web feature from NASA.

And every once in a while, don’t forget to look up.

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Plants vs. the World

A stinging nettle.

The world is a rough place to grow up. Just ask a stinging nettle. Credit: Ashley Braun/All rights reserved.

Life as a plant can be stressful. Once, or rather, if, you sprout where you’re planted, you’re faced with some immediate limitations. Let’s hope you have just the right exposure to sunlight, water, and nutrients. Maybe not too much wind or competition for space. And watch out for herbivores.

But that’s about all plants can do, right? Just watch.

While plants do have some obvious defenses (thorns, toxins, tannins, and the like), we humans often think of plants as being passive. We don’t give them much credit for taking a stand against the world. “Vegging out” means sitting around doing nothing, unaware and unresponsive. Yet researchers are finding many examples of plants actively responding to the world around them and in a variety of ways.

Yo, Romeo: Smell Ya Later

Tall goldenrod plant with fly-induced gall.

I forgot to mention that gall fly larvae spit causes huge galls (ball-shaped masses) to form on the goldenrod’s stem. They then live inside the gall all winter, sucking nutrients out of the plant from the inside. No wonder the plant is pissed. Credit: Phil Myers, Museum of Zoology, University of Michigan-Ann Arbor/Creative Commons Attribution-Noncommercial-Share Alike 3.0 Unported License.

Take smelling, for example. In 2012, entomologists at The Pennsylvania State University documented both in the field and in the lab evidence of a plant that, when exposed to the smelly male sex hormones of a long-time enemy, is able to beef up its chemical defenses against it.

It seems that once the tall goldenrod plant, Solidago altissima, gets a whiff of a romantically inclined male goldenrod gall fly, Eurosta solidagini, it begins releasing the defense hormone, jasmonic acid, which is a real turn-off to lady flies. Particularly, as it turns out, when they’re looking for a place to lay their eggs, which hatch into hungry little caterpillars and only have a stomach for tall goldenrod.

Male flies release clouds of this pheromone “perfume” when they’re in the mood for love, sitting on the leaves of a tall goldenrod plant and waiting to attract a female. After they mate, the female flits away to find a suitable nursery plant for her bug babies. In this search, she goes from plant to plant, sticking her egg-laying organs into goldenrod buds and getting a “taste” for the plant with her feet and ovipositor. If she likes the taste, she lays her eggs. If not, on to the next plant.

However, once a plant is exposed to the male flies’ odor, not only are they less likely to have female flies inject their eggs into them, but to a large extent they also avoid being eaten by other hungry insects. Jasmonic acid must taste terrible to a would-be mother goldenrod gall fly. But the musk of a male fly apparently smells like heaven to a nervous goldenrod.

Beating the Heat

Another very real concern for plants is heat stress, which is only going to get worse as the global climate warms. The United Nations Intergovernmental Panel on Climate Change is in the process of releasing its latest series of reports on global warming and its impacts on the natural and human worlds. A part of one of their reports was leaked before being published, but it apparently has dire warnings for agriculture.

According to the New York Times:

In a departure from an earlier assessment, the scientists concluded that rising temperatures will have some beneficial effects on crops in some places, but that globally they will make it harder for crops to thrive—perhaps reducing production over all by as much as 2 percent each decade for the rest of this century, compared with what it would be without climate change.

And, the scientists say, they are already seeing the harmful effects in some regions.

Heat waves have already taken a toll on crop production in recent years (see Europe in 2003). A growing body of research suggests that important crops such as corn and soybeans are more sensitive to extreme heat than previously thought.

What does “extreme heat” mean? The mid-80s. Having grown up with sticky Midwestern summers, that doesn’t even sound that hot, but it translates to a sudden drop in production for these plants.

Even so, plants do have ways to cope with heat stress. Researchers at Iowa State University have recently uncovered some of the molecular pathways that plants use to deal with stress. From a press release:

The research takes a close look at what happens to the model plant Arabidopsis at a molecular level when faced with environmental stress. It involves a process called unfolded protein response, which can act as an alarm system when the plant senses harsh conditions. When the alarm goes off, the plant activates survival measures that can protect crops from succumbing to weather extremes.

Considering the warming world facing plants, they’re going to need these kind of defenses to stay alive. And why should we expect them to just sit back and watch?

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I Flew Over the Cuckoo’s Nest

Baby got snack: A Reed Warbler feeds a Common Cuckoo in its nest.

Baby got snack: A Reed Warbler feeds a Common Cuckoo in its nest. Credit: Per Harald Olsen/Creative Commons Attribution-Share Alike 3.0 Unported license

Earlier this week, I was researching and writing a story for Natural History Magazine about some cuckoos that have taken on the plumage patterns of local hawks and other raptors in order to frighten away other birds from their nests.

“Dressing” like a known predator allows the cuckoos to swoop in and lay their own eggs in the nests, tricking unsuspecting sets of bird-parents into raising the cuckoos’ young. This sometimes happens to comedic effect when you consider how much bigger cuckoos can grow than their host parents.

(By the way, you should read the bio of Thanh-Lan Gluckman, one of the scientists who published the study on cuckoo-raptor plumage; she has taken a fascinating, if self-described “convoluted,” path to evolutionary biology.)

In the course of researching this story, I followed an interesting tangent: In 350 B.C., the ancient Greek philosopher Aristotle made observations in his work “The History of Animals” about both the behavior of cuckoo parents and their striking resemblance to hawks. Stringent scientific studies today support these observations as well as the maxim shared with me by my college ecology professor: Basically, ecology confirms what we already know.

One thing I found amusing about reading these early descriptions was the moral lens through which the cuckoo is viewed for its habits (emphasis is mine):

The cuckoo, as has been said elsewhere, makes no nest, but deposits its eggs in an alien nest, generally in the nest of the ring-dove, or on the ground in the nest of the hypolais or lark, or on a tree in the nest of the green linnet. It lays only one egg and does not hatch it itself, but the mother-bird in whose nest it has deposited it hatches and rears it; and, as they say, this mother bird, when the young cuckoo has grown big, thrusts her own brood out of the nest and lets them perish; others say that this mother-bird kills her own brood and gives them to the alien to devour, despising her own young owing to the beauty of the cuckoo … The cuckoo shows great sagacity in the disposal of its progeny; the fact is, the mother cuckoo is quite conscious of her own cowardice and of the fact that she could never help her young one in an emergency, and so, for the security of the young one, she makes of him a supposititious child in an alien nest. The truth is, this bird is pre-eminent among birds in the way of cowardice; it allows itself to be pecked at by little birds, and flies away from their attacks.

~Aristotle, “History of Animals,” Book IX, Part 29, 350 B.C.

Yes, the cuckoo is full of “cowardice” and is quite aware of it, thank you. On the other hand, the foster-parent bird purportedly “despis[es] her own young owing to the beauty of the cuckoo.” Naturally, they’re going cuckoo for cuckoo chicks!

This tangent took me further down the rabbit hole to the 1891 work of Alfred Russel Wallace, “Darwinism: an exposition of the theory of natural selection.” Wallace makes further reference to how similar several species of cuckoos appear to sparrow-hawks and other “aggressive” birds, despite–or rather because of–the cuckoos’ “exceedingly weak and defenceless” nature.

Darwinism: an exposition of the theory of natural selection, with some of its applications

“Darwinism: an exposition of the theory of natural selection, with some of its applications,” by Alfred Russel Wallace, 1891.

It’s worth noting that not all cuckoos (the family Cuculidae) exhibit these parasitic adaptations to reproduction. But approximately 41% of them do.

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