Category Archives: science

The Nobel Prize and Fuzziness Between Chemistry and Biology

“When you get into University, you learn that Biology is really Chemistry, Chemistry is really Physics, Physics is really Math.”*

Many years ago, a friend sent me a version of that quote among a whole host of other quotes that he’d collected over the years. When I first read it as a chemistry undergraduate, I liked the way it broke down barriers. Because even though I studying chemistry, I secretly wanted to understand how life worked.
But even though biology motivated me, I never took a single undergraduate biology course. That choice haunted me, particularly when I chose to go to graduate school and work in a biochemistry lab. During my first year of graduate school, I struggled understand the nuts and bolts of gene transcription, while still memorizing nucleic acid and amino acid structures. My note to readers out there: If you’re interested in life, you’d be well served to take some biology even if you don’t want to major in it.

But during Nobel Prize season, chemists sometimes get cranky when a biological topic gets the prize, like this year with the award for G-protein coupled receptors to Robert Lefkowitz of Duke University and Brian Kobilka of Stanford University. Derek Lowe described the work and his own take on this divide on his blog. “Biology isn’t invading chemistry – biology is turning into chemistry.

Even the field I studied in graduate school, then known as bioorganic chemistry, has evolved into chemical biology. As I tried to synthesize my understanding of molecules with an understanding of how cells worked, I hated those shape pathway diagrams in cell biology papers. I didn’t want to understand biology in the context of red circles, blue squares, or green triangles– I wanted to know what that meant chemically. When I was in high school, the last formal biology course I took, I frustrated my mother as I tried to learn glycolysis because I couldn’t just memorize the steps, I wanted to learn something about what was actually going on. A nurse, she dug through her old textbooks to find information that might satisfy me. I soon forgot what we found, but it was the foundation for my chemical curiosity about biology.

Science has to move where the questions are, and some of the greatest questions out there come down to the fundamentals of how life came to be and how it works.  From one perspective, you might say that chemistry could (or even has) become a toolkit for biology. But really it’s more than that. Chemistry has to be part of the biological question, and the GPCR discovery helped to make that fundamental connection between the two.

The names of the prizes are part of the problem, but I really hate the walls that some scientists like to put up around their work. Creativity and innovation can be messy, and it often happens at those  fringes of a field rather than within the safety of the center. Drawing lines in the sand provides some organization and context. Categories are useful, and researchers can easily cross them. But organizational lines sometimes grow into concrete barriers, and the minute that scientists have to pull out heavy machinery to scale those walls, we’ve all lost out.

*Some versions of this also include “and Math is really Hard.” The Math=Hard stereotype has always bugged me.

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The Science of Monet

Before we left New York City, we finally made it to the New York Botanical Garden. What finally kicked us into gear to make the trip was a special exhibition about Monet’s Garden at Giverny (It closes October 21).

Though Monet can sometimes loom on the edge of a giant Impressionist cliche, I’ve always been a fan. In college, I slept under a comforter covered in one of his famous garden bridge scenes. And during college, my roommate and her mother went to Giverny on a summer trip. “If you get the chance,” she said, “just go.”

I took her advice nearly 5 years later as I traveled in France with friends. We were in Paris for a few days, and I’d spent time in the city before.  So one day while they did some city sightseeing, I hopped on a train to Vernon and a bus to Giverny.

Though I’m sure the garden is amazing throughout the growing season, it washed over me in waves of color delight in May, like eating a multi-course artisanal meal. Monet harnessed as much creativity in his garden design as he did as he when spreading those paints across the canvas. I’d always imagined that some of the pinks and purples that worked their way into the water lilies were enhancements, creative license that Monet took in his paintings. But the day I was there, the cloudy sky and the surrounding blooms imbued the water with rosy hues that were factual rather than fictional.


My brain didn’t quite make this leap as I wandered through the garden, but over time I’ve realized that– though I’d never describe him that way first– Monet was a scientist. He experimented with a garden, and his paintings are his lucious lab notebook.

The NYBG does a nice job of recreating his garden and framing Monet as a botanist. It’s a stunning exhibit, and a good proxy of the real thing (Though if you’re in France, as my roommate said, just go!). But the analogy is far broader– he was a creative observer. To top it off, almost any art history discussion of Monet talks about his declining eyesight and the increasing abstraction in his work. He’s a classic example when psychologists talk about color perception. Monet was scientist, observer, case study, and an amazing artist all in one.

All photos are mine taken in May 1999 and May 2012.

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Notes on the leaky pipeline: realism or disillusionment? [Updated]

[Update in italics: May 3, 2012] After I wrote this post PLoS ONE published a paper that fits nicely with the points I was making.] 

Beryl Benderly’s blog post over at Science Careers caught my eye yesterday because she mentions a 2008 report from the UK about the retention of women  chemistry PhDs in academia. As expected, the women are moving away from academe. By the end of their PhDs only 12% of women want academic research careers in chemistry compared with 70% who are in the first year of the PhD. Those are compared with a drop from 60% to 21% for men.  (A disclaimer: I write regularly for Science Careers, but I wasn’t involved in this blog post in any way.)

Beryl takes a positive spin on this data:

The figures are still way above the percentage of new Ph.D.s who have any realistic chance of landing a job on the tenure track (at least in the United States). Thinking about the welfare of the young scientists who have devoted many years to preparing for their careers and are about to begin them, it does not appear “alarming” to me that they have traded in their formerly unrealistic notion about the possibility of landing an academic post.

I’m not so positive based on my anecdotal experiences. As a female chemistry PhD who flew the academic coop immediately after graduation (more on that here, here, and here), I’m one of those safe people, someone who walked away from the bench and hasn’t looked back. So as soon as young PhDs hear my story, they often delve into their own questions about the research life. What do I often hear? Confusion, disillusionment, and questions about how they can use their science in productive ways. A realistic picture of their academic prospects is a first step, but I’m not sure that the awareness provides a  bridge between their PhD and how they might use it in the workforce.

This particular report talks about the role of isolation in the choice to leave academia. If you’re in an academic setting and plotting a nontraditional career move, that decision often increases that feeling of isolation. So in some cases, a young scientist has to make their immediate professional social situation worse in order to make it better.  So step one is often finding a mentor or a like-minded support system and learning new skills, but all while you’re trying to maintain a presence in your laboratory. That’s easier said than done.

I realize that young PhDs who are happy in academia are not seeking me out, so I probably have an unusually gloomy picture. But I don’t think the academic system has addressed how it can broaden the career skills of young PhDs and support skilled scientists who become interested in policy, business, law, or education. I recognize that building a satisfying career involves incredibly personal decisions, and no career counselor or academic department can map that out for you. But better support for career development could help more PhDs who opt out of academia or research feel like extensions of their scientific community rather than renegades.

The PLoS ONE paper describes trends that I’ve noticed anecdotally. PhD students are less interested in the traditional academic research track by the end of their degrees. At the same time, they aren’t necessarily prepared for,  interested in, or aware of the jobs that might be available that would capitalize on their skills. Faculty members seem to be relatively neutral about alternative paths, and what I’ve noticed talking with some young scientists is this general sense that they want to do “something else” but without any sense of what “something else” might look like.

Figure 5. Share of students finding particular work activities interesting/uninteresting. Respondents indicated how interesting they would find each of six kinds of work when thinking about the future.

 

And if you don’t want to take my word for it, here’s what the researchers have to say about the way that student interests, encouragement, and career opportunities aren’t lining up.  (Emphasis is mine).

Second, respondents across all three major fields feel that their advisors and departments strongly encourage academic research careers while being less encouraging of other career paths. Such strong encouragement of academic careers may be dysfunctional if it exacerbates labor market imbalances or creates stress for students who feel that their career aspirations do not live up to the expectations of their advisors. In the context of prior findings that students feel well-informed about the characteristics of academic careers but less so about careers outside of academia [17], our results suggest that PhD programs should more actively provide information and training experiences that allow students to learn about a broader range of career options, including those that are currently less encouraged. Richer information and a more neutral stance by advisors and departments will likely improve career decision-making and has the potential to simultaneously improve labor market imbalances as well as future career satisfaction [23], [24]. Advisors’ apparent emphasis on encouraging academic careers does not necessarily reflect an intentional bias, however. Rather, it may reflect that advisors themselves chose an academic career and have less experience with other career options. Thus, administrators, policy makers, and professional associations may have to complement the career guidance students’ advisors and departments provide.

So let’s figure out how to bridge the disillusionment. I can’t think of a bigger waste of scientific talent than to have young researchers floundering because they don’t know how to bring their skills into a useful and productive career.

As a postscript, check out my fellow blogger Chemjobber, who doesn’t pull any punches about all things job- and chemistry-related.

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Cocktail hour in the Facebook age

Whether you’re a scientist, a writer, or a science communicator, most of us spend some time at conferences, or more appropriately noshing on cheese, fruit and other snacks, and sipping free wine or beer at the end of the day. And then depending on how well you know the other people in the room, you start conversations about who you are, what you do, or what you’ve been up to lately.

Last Friday, I mingled in one of these rooms, networking with my colleagues, and I was struck by how Facebook is changing these types of conversations.

First of all, I don’t routinely connect with my work colleagues on Facebook (usually Twitter or LinkedIn, first). Maybe they chose to connect with me, or I’ve had enough conversations with them that I chose to connect with them there. I’m not unusual. A Pew Internet study indicates that about 10 percent of our “friends” are colleagues. But I ran into several of them last week. And when I made conversation, I realized that many of the things that were once polite conversation starters are now old news because they’ve already had a life on Facebook.

With one colleague we almost had a little joking game about it, she says, “How are you? I saw on Facebook that your husband finished up his Ph.D. and you’re still making all that pottery.” Check and check. “So what else is going on with you?”

But I also don’t assume that people stalk my Facebook page or my Twitter feed. So, if you offer up information that already appeared elsewhere, are you being social and looping people in on life information that they might not have heard? Or are you that boring person droning on about information that the other person is hearing for the third or fourth time? Social media offers opportunities to connect with people we might never meet otherwise, and I see that as primarily positive. But it also can give us a sense of knowing people when we’ve never met them in person or a false sense that I’ve had a conversation with someone when I haven’t.

In certain ways, I feel like this idea isn’t incredibly different from my experience as a freelancer, working closely with editors who I only communicate with via email or phone. I remember meeting one long-time editor at a conference a few years ago. He was standing 10 feet from me, but asked loudly, “Is Sarah Webb here?” I’d probably written at least 15 articles for him by that point, and it was funny but natural that he wouldn’t recognize me in a crowded room.

Maybe as a journalist I’m oversensitive to the idea of what is news. But I don’t think we can completely ignore that choice to share information, and that nagging question of whether other people are interested and whether we’re beating a dead horse. For now I think I’ll take my cocktail hour lead from my colleague. Here’s what I know, and what else is new?

Image courtesy of public-domain-image.com

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Science Communication Without Borders: reflections on ScienceOnline 2012

 I’m hardly a newbie to science communication. But last week was my first trip to ScienceOnline. The energy buzzing around that conference for 72 hours made me flash back a decade to when I was still in a chemistry Ph.D. program but desperate to reboot my career without leaving science behind.

At that point, I knew I wanted to think about broader science questions and communicate science to more audiences. So I spent time working in a hands-on science museum, took a science journalism course, and eventually launched my science writing career. But even though science writing has fewer defined boundaries than the research world does, I still run into cultural norms that don’t always fit with how I view myself. For example, many journalists will tell you that their core responsibility is to inform, but not to educate, the public. I can see where the idea comes from, but I firmly believe that education is an important part of what I do. As a result, I’ve continued to keep my hand in museum or exhibit work, or I try to keep writing for children in my mix of projects. I’m not a professional educator, but if I’m doing my job well, I’m a stealth educator.

ScienceOnline 2012 provided a Science-Communication-Without-Borders experience: scientists, journalists, bloggers, educators, and many people who hyphenate those categories, all coming together to discuss issues questions and how we think about all the issues of taking the ideas we’re passionate about and bringing them to broader audiences. It’s not just that people are friendly, but by virtue of being at an Unconference and knowing the diversity of perspectives, people are set up to look at their work and assumptions from a new perspective. I’m still a journalist, but I’ve always benefited from my past and seeing the scientist side of the equation. Because I’m still an educator at heart, Science Online brings me into a fold of people who make that their life’s work.

So other than coming back to my home office with a renewed sense of enthusiasm, what did I take away from Science Online?

Nuggets of writing craft:

  • In a session about assembling book research, David Dobbs (Twitter: @David_Dobbs) offered an incredibly low-tech tip for a high-tech meeting: keep a journal. At the end of each day, sum up what you’ve learned and what you found intriguing in that day’s work. Trust nothing to memory, he says, and those summaries will help you find key thematic connections.
  • He and Deborah Blum (Twitter: @deborahblum) also led an amazing session about writing structure with both visual and audio analogies for crafting stories. Structure is visual, musical, and a bit like a chess game. That mix of beauty and strategy keeps me coming back every day. (If I find a link to audio or video from that session, I’ll follow up and post it).

Nuggets of Tech and Traffic:

  • For techie tips from the book research session: check out Maryn McKenna‘s tumblr post here. (Twitter: @marynmck)
  • Explainers, articles that offer background, are great tools for providing more context on your site. Not surprising. They’re also great tools for driving traffic. If you point out an explainer, those links get more hits. If you point out an explainer and directly encourage your reader to click on it, even better. I believe that nugget emerged from a back and forth between Maggie Koerth-Baker (Twitter: @maggiekb1) and Bora Zivkovic (also known as the Blogfather, Twitter: @BoraZ).
  • The e-book world is exploding, and I love reading on my Kindle (I don’t mean that as a product endorsement. I had fun playing with my dad’s iPad over the holidays, too.). The ways for writers to publish their own work for these devices are expanding. There’s Apple’s iBooks Author, but read the fine print about being locked into their store. The Atavist, publisher of long form e-journalism, is also beta-testing software that would allow people to publish their work in any of the current e-formats. See more on that here, and learn more from this blog post by Christopher Mims over at Technology Review. (Christopher is on Twitter at @mims). The conference wiki also has an incredible list of links and information on e-book publishing.

My post conference thoughts are still simmering, but I’ll continue to use those 3 days as motivation NOT  to box myself in. And I also just solidified my connections with people I can call on when I want to think outside my comfort zone.

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In search of manatees

Though my current home is in the Big Apple, I was born and raised in the Sunshine State and return on occasion to visit my family. This time our trip south also included an animal-based day trip to Homosassa Springs Wildlife Park in search of manatees.

manatee closeup

 

In the area around Crystal River, particularly this time of year, manatees huddle in the warm springs and near power plants and even around the docks and waterways. We picked a bad year to make this trip– the temperatures hovered in the 70s, balmy for December, and the manatees didn’t need to come in to shore to stay warm. We could have headed out on the water to snorkel near them, but we didn’t have time or the right gear (Next time!).

Lucifer, the hippopotamus So we did the next best thing and headed a few miles south to Homosassa Springs Wildlife Park. On the boat ride from the park entrance, our guide (whose accent indicated pointed to origins farther north, say Long Island) gave us the twisting Floridian history of this park, originally set up as an exotic animal park that including monkeys and a hippo (Lucifer, who is still in residence).

When the State of Florida took over the park, they turned it into a showcase of native animals. So in addition to the half dozen manatees, some of whom were injured and others of whom are permanent residents, we saw Florida panthers, river otters, and a whole host of cranes, flamingos and raptors.

As a Florida kid, I’d heard a lot of the manatee basics before. They’re marine mammals, slow moving, and herbivores, and they’re often injured in boating accidents. But my image of those boating accidents had always been run-ins with slashing speed boat propellers. That’s one possible injury, but the big danger is that collisions will watercraft can lead to broken ribs and punctured lungs. Unable to float (and breathe), they’ll drown. Because of their migratory patterns from the warm Florida waters in winter before ambling north, sometimes as far as New York, they aren’t bred in captivity. To maintain these patterns, captive breeding programs can’t help support the wild populations, they need to learn them in the wild.

active river otters
River otter
Sandhill crane
Florida sandhill crane

 

 

Photos by Preston Foerder

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A Glimpse of our Space Future

Sputnik1
Sputnik 1, the little Russian satellite that launched the space race in 1957

The American Museum of Natural History‘s new exhibit, Beyond Planet Earth, which opened last Saturday through August 12, 2012, provides a window through the past and an optimistic glimpse at the future of space exploration. As I moved through the historical portion at a press preview last Tuesday, Russian spacecraft pinged, and news reports captured the excitement and enthusiasm of historical moments, press conferences that opened up the world beyond our atmosphere.

I grew up in Florida in the Space Shuttle era, but I never saw a shuttle launch. My family tried to go once, and we thought we’d miss it because of traffic, only to arrive just in time to have the launch scrubbed seconds before scheduled liftoff. Years earlier I’d watched the TV enraptured in my elementary school library as the first Space Shuttle launched. I remember slipping on ice between two of my middle school classes  on a frigid morning in January 1986 — within a couple of hours word spread through the hallways of the Challenger explosion. So my personal piece of space nostalgia came when I walked by the case with the frangible nuts– the piece of the space shuttle that released the engine and rocket boosters and allowed the spacecraft to be reusable.

In many ways, the Space Shuttle was my window on exploration, on space, on science. The  future of understanding worlds beyond Earth seems far less focused, and though exciting and innovative, far less certain.

Sarah with rover
Sarah with the AMNH's Mars Exploration Rover

I paused at the Mars Exploration Rover long enough for a photo. Spirit and Opportunity launched the same year that I started my science writing career, and that mission marks a very personal milestone: a new career, a new adventure, a personal exploration.

But the real meat in this exhibit comes through the journey into the future, a world of Kevlar-sided Moon-homes the size of camping trailers, liquid mirror telescopes, the technology to provide enough water to drink on the Moon or beyond.

The Virgin Galactic Spaceplane: the future for astronauts and space tourists?

I had never thought about mining asteroids, but space mining for rare elements for cell phones and electronics seems plausible, maybe. After our recent near-Earth asteroid experience within the last two weeks, one interactive game that allowed me to use various strategies, bombs and mirrors to divert such disasters.

My asteroid diversions probably line up with Dennis Overbye’s inner 6-year-old boy delight at bombing Mars (see his New York Times review). The exhibit includes a touch table that allows you to terraform Mars, by building factories, setting off bombs. It took me a while to get to a point where such effects might make Mars warm enough to be comfortably habitable. And I couldn’t help but wonder, is this a good idea?

I spent the most time looking at the new Curiosity rover that’s heading to Mars next weekend and learning about the prototype for a Mars spacesuit. Dava Newman of MIT talked about the suit that uses mechanical pressure against the skin instead of a pressurized dough-boy look. The resulting suit works like high-tech athletic gear, sleek and far more streamlined for moving and climbing.

BioSuit by MIT Aeronautics

At the press conference before the  preview last Tuesday, astronaut Mike Massimino talked about his early interest in space exploration that came out of his childhood visits to the American Museum of Natural History: “There were no astronauts living on my block in Long Island.” This exhibit is a lovely tribute to explorations past and a look at the best possible future. I hope that future generations have the same chance to explore worlds beyond Earth.

Photo credits:

Sputnik: © AMNH\R. Mickens

Sarah and Rover: Carol Milano

Spaceplane and BioSuit: © AMNH\D. Finnin

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Seeing the forest for the Birch reduction

This post is a part of the Chemistry Carnival hosted by Chemical & Engineering News in celebration of the International Year of Chemistry. Check there later in the week to see what others have blogged or look for the #chemcarnival hashtag on Twitter.

 

I spent nearly a decade of my life doing organic chemistry. Sometimes I defied the norm and carried out reactions in water. But I never quite got over my first. My first real reaction in a research laboratory was a Birch reduction.

This is a simplified scheme (and I lost my last working copy of ChemDraw when my computer before last crashed). I was doing the reaction on a steroid, converting the aromatic A ring of an estrogen to an androgen. But if you’re interested in the reaction details, other websites can tell you all you ever wanted to know about aromaticity, ammonia, lithium, and the quench with ethanol.

What sticks in my mind was the process of setting up and carrying out that reaction. I careful prepared dry glassware, I assembly of the glassware from the bottom up.  I made sure I had enough dry ice and liquid nitrogen, and made sure that the flow of nitrogen gas was both slow and steady. Most of the techniques I had to learn to run every other reaction in my chemistry career started with that Birch reduction.

I tried to be patient as ammonia gas slowly condensed in my reaction mixture. I added bits of soft lithium metal that had yielded to snips of the scissors. I watched the solution deepen to brilliant blue as unpaired electrons worked their magic. Little did I know that the rest of my chemistry career would be filled with white powders or vaguely yellow goo.

Fortunately, my adviser watched me like a hawk, making sure I didn’t quench the reaction with ethanol too soon or too quickly. I’d learn that lesson the hard way in my next laboratory, when I got impatient from waiting hours for a reaction mixture to warm to room temperature. I assume that most chemists learn the hard way at least once?

Occasionally my former chemistry colleagues and friends will ask me, “Do you miss the lab? Do you miss doing reactions?” Day-to-day, I don’t. I’m pretty happy in front of my computer. But occasionally I am nostalgic for the rhythm and physical ritual of setting up a Birch reduction. At the end of the day, I always felt satisfied that I’d both worked hard and produced a white, fluffy powder.

Image Credits: birch forest photo by tumpikuja via iStockphoto; synthetic scheme by V8rik via Wikimedia Commons

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Pondering medium and “The Cave of Forgotten Dreams”

replica of a Chauvet Cave painting from a museum in Brno, Czech Republic

I’ll admit a kind of mixed relationship with 3D movies. Done well, I love experiencing the depth, but it seems to me that 3D should be an artistic choice for its ability to convey an experience, rather than just a way to make sure that people see a movie in the movie theater.

Cave of Forgotten Dreams, Werner Herzog‘s new documentary, is the perfect match of its subject, Chauvet Cave in southern France, and the medium. A 2D film would not do this 30,000 year old cave and its intimate, yet expansive space, justice. The 3D glasses aren’t a gimmick, but a window to a moving diorama, a museum experience, a sacred journey.

This cave and its paintings were buried in rock slides thousands of years ago, only to be rediscovered about 15 years ago but closed to nearly everyone except the scientists who study it. So this space is mysterious, exclusive, and wondrous. Science meets art on every level: stalactites, stalagmites, natural artwork from above and below. But the undulating walls of these caves mesmerized me as they must have mesmerized the artists who drew on them. Cattle, bears, and even a mammoth, simple forms integrated into the movement of the walls, ancient, but fresh as if they were painted just a few years ago.

The film is an experience, well worth the money. But I found Herzog’s chosen coda to the film jarring. He talks about crocodiles that live in the warmed waters next to nearby nuclear plants. His comments were about the passage of time, how humans have changed the world and what life on earth might be like in another 30,000 years, and how those crocodiles might experience this world. Those could be worthy topics, but it’s unsatisfying information that leaves a giant question mark, with little context, at the end of a beautiful film.

With such a perfect match in the film, I’ve been thinking about subject and medium more in my work. I primarily work in printed words: the dizzying choice of nouns and verbs etches clear lines, subtly shades or brings out a new color. Words change color on radio or accompanied by video. When I spend hours in the pottery studio, I shape emerging forms from clay, add detail, think about designs on a surface.

Herzog matched his medium to an amazing subject, a cultural gift and a way to share the experience of this delicate space with a much wider audience. It’s a museum piece (in the best sense of the word) as much as a film. Ancient painters depicted their world, animating their world on a waving canvas of stone. I hope to channel an iota of that creative synergy.

Image Credit: The Adventurous Eye on flickr

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A ruler among science books

Though I’d read the excerpt adapted for the New York Times magazine, picking up The Emperor of All Maladies: A Biography of Cancer by Siddhartha Mukherjee, with its regal and imposing title, was just a little intimidating. But open the first page and the language propels and compels the reader to follow the disease, its history, and those who have faced it, both doctors and patients.

This is the story of cancer infused with historical depth, scientific rigor, caring, compassion, and luscious language. Mukherjee crafts the text with such skill, infusing human stories, history, and a physician’s perspective among the timeline of cancer as it’s affected human life and health. As I worked my way through this book, I found myself underlining sentences, many of them juxtaposing the hauntingly beautiful with the terrible.

Cancer, Auerbach argued, was a disease unfolded slowly in time. It did not run, but rather slouched to its birth.

Or when describing Susan Sontag’s leukemia:

“A moody, saturnine leukemia eventually volcanoed out of Sontag’s marrow.”

Although I’ve never done cancer research, I’ve learned a lot about it in my reporting. But what I’ve learned is episodic: a cellular pathway, a policy point, or a set of treatments. This volume pulls those episodes together like jewels on a necklace, creating a comprehensive picture and an understanding of a disease that’s as powerful and compelling as the stories of the patients. Not only was this book beautiful to read, but I’ll be better at reporting about cancer because I’ve read it.

Image: Human melanoma cell dividing. Credit: Paul J.Smith & Rachel Errington. Wellcome Images

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