Book Review – The Voyage of The Beagle

Some readers might joke that I’m roughly two centuries late with this article, and I admit that they have something of a point. Charles Darwin’s “Journal of Researches into the Geology and Natural History of the Various Countries Visited by the H.M.S. Beagle, Under the Command of Captain FitzRoy, R.N., from 1832 to 1836(more popularly known as “The Voyage of the Beagle“) was first published in 1839, two decades before his landmark “On the Origin of the Species.” This latter work has obviously attracted significantly more attention and controversy over the years, but in its own quiet way, “The Voyage of the Beagle” is just as fascinating a window into Darwin’s life and thought. The work that first made him a celebrity in the scientific circles of London is worthy of consideration even now.

Perhaps the most important reason to read “The Voyage of the Beagle” is the way it humanizes Darwin, one of the most revered figures in all of science. High school biology textbooks usually present the naturalist in a photograph like this one:

Courtesy of Wikimedia Commons

Courtesy of Wikimedia Commons

Darwin’s public image follows from this portrayal as a proper, elderly, luxuriantly bearded English gentleman. Yet as Tetrapod Zoology blogger Darren Naish argues, this image lends itself to a stereotype of scientists as “oddballs that operate on the fringes of society.” Naish fears that students may fail to identify with this depiction, believing that science is something for the old and serious rather than the young and curious. “The Voyage of the Beagle,” in contrast, shows the reader a youthful Darwin, a man closer to the following fresh-faced portrait:

Courtesy of Wikimedia Commons

Courtesy of Wikimedia Commons

Anecdotes from throughout the book give life to Darwin as a young man, closer in many ways to a frat boy than a Fellow of the Royal Society. He tries to ride the famous Galapagos tortoises when he first encounters them; he tempts temperate Tahitian islanders into sharing swigs of spirits from his flask; he nearly knocks himself out with a pair of bolas as a crowd of sniggering Argentinian gauchos looks on. He is far from all-knowing or authoritative; he is simply a young scientist out in the world, trying to make sense of it all while having fun in the process.

The way the book hints at this process is its other great strength. “On the Origin of Species” is a singular, towering argument, a comprehensive outline of the evidence for evolution and a thorough discussion of the objections that could be raised against the theory. At the time of “The Voyage of the Beagle,” however, Darwin was very much still piecing the theory together. The reader can see hints of the future with Darwin’s treatment of the Galapagos finches or the fossil history of South America, but there is also an obvious frustration, a sense that the scientist is perplexed by the evidence and lacks a complete framework into which it can be placed. The book is a humbling reminder that science takes time, that a great discovery is almost always the result of years of painstaking work instead of a sudden flash of insight.

Although “The Voyage of the Beagle” is a long read, it is certainly a rewarding one. Young scientists can take heart from its portrayal of the great Darwin as one of their own, while the general public can enjoy learning more about the thought process behind what is arguably the most important scientific theory ever to be devised. And all readers can delight in the beauty of Darwin’s eloquent descriptions of his travels, such as this extract from his time sailing towards New Zealand: “It is necessary to sail over this great ocean to comprehend its immensity. Moving quickly onwards for weeks together, we meet with nothing but the same blue, profoundly deep, ocean. Even within the archipelagoes, the islands are mere specks, and far distant one from the other. Accustomed to look at maps drawn on a small scale, where dots, shading, and names are crowded together, we do not rightly judge how infinitely small the proportion of dry land is to water of this vast expanse.”

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Secret Ingredient – The Science of MSG

As discussed in last week’s article, some creative scientists are examining the changes in Hawaiian seafood menus over time for useful data about fishery abundance. If researchers were to study another set of menus, those of Chinese restaurants in the United States, they would find a similarly interesting trend: from the early 1970s onward, many menus began to advertise the absence of monosodium glutamate, or MSG, in their cuisine. The U.S. Food and Drug Administration, however, has labeled MSG as a “generally recognized as safe” food ingredient since 1959. A sudden change in public perception led to these changes, but the roots of that perception are surprisingly obscure.

Courtesy of closter1chinesefood.com

Courtesy of closter1chinesefood.com

Although MSG was only formally discovered in the early 20th century by Japanese chemist Kikunae Ikeda, the compound from which it is derived, glutamic acid, is one of the 20 amino acids necessary for proteins (and therefore life itself). The body recognizes the importance of glutamic acid through the sense of taste in foods like asparagus, tomatoes, cheese and meat. Just as the tongue’s taste buds detect sodium chloride as salty, sucrose as sweet, or quinine as bitter, they register glutamic acid as its own unique taste, designated by Ikeda as “umami,” a Japanese word for “delicious” or “yummy” that is often translated as “savory.” MSG is simply glutamic acid that has been stabilized through the addition of sodium; for comparison, MSG contains one-third the amount of sodium per unit volume as table salt.

Asian cooking traditionally derived umami flavor from ingredients such as seaweed (from which Ikeda first isolated glutamic acid) and dried tuna, but by the 1950s, purified MSG was available to the United States as the seasoning Ac’cent. Restauranteurs and food processors were quick to adopt the ingredient as an inexpensive way to bolster the flavor of their products. No concerns were raised by the substance’s inclusion until 1968, when a Chinese-American doctor named Robert Ho Man Kwok reported feeling a number of ill effects after eating at Chinese restaurants in the United States.

As BuzzFeed’s John Mahoney outlines, Dr. Kwok hypothesized in the New England Journal of Medicine that his symptoms may have been “caused by the monosodium glutamate seasoning used to a great extent for seasoning in Chinese restaurants,” and after the New York Times covered the story, a flurry of experiments were conducted to confirm his suspicions. Many of these studies did report an association between high doses of MSG and symptoms such as headaches and flushing, but they lacked the proper scientific rigor of double-blind design (in which both the experimenter and subject do not know which treatment is being administered) or placebo controls.

Better designed experiments over the following decades failed to confirm the results of earlier research, and a comprehensive review by the Federation of American Societies for Experimental Biology concluded that were was no association between MSG and short- or long-term health issues in humans. Despite this research, a number of groups have continued to advocate about the perceived dangers of the compound, and MSG has been absent from baby food since 1969. Yet as the scientific consensus stands, one should feel no fear in enjoying a plate of egg foo young from a Chinese restaurant, even if the menu is silent about the presence of MSG.

Off the Table – Hawaiian Fisheries

For most restaurant diners, a menu represents only a pleasingly difficult decision of what to eat (or, in some cases, a soon-to-be empty wallet). Yet for tourists in Hawaii throughout the first half of the 20th century, menus represented a colorful way to remember their time in an exotic land, and many diners took their menus back with them to the mainland. For marine ecologist Kyle Van Houten of Duke University, these souvenirs serve an unexpected purpose: by studying the changes in the availability of different fish species on menus from the islands, Van Houten and his colleagues were able to estimate the changes in the local fish populations over time.

Courtesy of the New York Public Library

Courtesy of the New York Public Library

Ecologists usually employ more precise information from commercial fisheries and governmental organizations to estimate changes in the ocean, but as Van Houten explains, fishery records are spotty before Hawaii’s statehood in 1959, and “there is a gap in commercial fishery data that we need to fill.” Menus from before 1940 commonly listed a variety of fish collected from near the islands’ shores, including reef fish, jacks and bottomfish. By Hawaiian statehood, however, these species were present on less than 10 percent of menus. Van Houten emphasizes that “the decline didn’t occur because of changes in people’s tastes in seafood,” citing interviews with native Hawaiians who reminisced about previously common reef species like goatfish. “The demand was there, but the fish weren’t.” The menus record the responses of restaurants to these changing times, with large, oceangoing fish such as tuna and swordfish becoming more prevalent entrees as the century progressed. These “large pelagics” appeared on 95 percent of menus by 1970, while the near-shore species had almost entirely vanished.

Although the menus are unable to explain why the changes occurred, Van Houten argues that tourism and agricultural development had the largest impacts on fish stocks. The present situation is little better; Conservation International reports that nearly 75 percent of Hawaii’s near-shore fish stocks are depleted or in critical condition, largely due to “[c]oastal development, land-based pollution, and destructive and illegal fishing.” Reef species are particularly vulnerable due the additional stresses of global climate change, which can cause coral bleaching and disrupt reef ecosystems. Mass bleaching has already been observed in the northwestern Hawaiian Islands, with more events predicted to occur.

Conservationists concerned about the future of the fisheries have begun to look into the past for the effective management strategies of native islanders. A recent study suggests that harvests under native management were five times that of current levels, and more importantly, that these catch rates were maintained for hundreds of years. This success has been attributed to aggressive management techniques such as the “kapu” system, in which fishermen found on a reef forbidden by the local ruler could be blinded or even put to death. While John Kittinger, the author of the study, acknowledges that these punishments were excessive, he stresses that “it’s easy to see there’s room to tighten up today’s enforcement efforts.”

Lying Through Big Teeth – Megalodon and “Shark Week”

The Discovery Channel‘s “Shark Week” began on Aug. 4 with a documentary titled Megalodon: The Monster Shark Lives. The program’s interviews and interpretive animations earnestly explored the biology of the massive shark, as well as the hazards a particular specimen, “Submarine,” poses to boating on the South African coast. This blend of science and violence helped earn the channel the highest ratings among all networks among male viewers aged 18-49 from Aug. 4 to Aug. 10. Such success might be considered a coup for science communication were it not for one minor detail: all reputable scientific work indicates that Megalodon has been extinct for approximately 2 million years.

At the very end of the two-hour program, the Discovery Channel briefly displayed the following disclaimer: “None of the institutions or agencies that appear in the film are affiliated with it in any way, nor have approved its contents. Though certain events and characters in this film have been dramatized, sightings of ‘Submarine’ continue to this day. Megalodon was a real shark. Legends of giant sharks persist all over the world. There is still debate about what they might be.” Many scientists have criticized this disclaimer as intentionally vague and misleading, claiming that the statement failed to explain the depth of the “dramatization.” In perhaps the most blatant omission, the network did not explain that the marine biologists used in the program’s interviews, Collin Drake and Madelyn Joubert, were completely fabricated talking heads portrayed by actors. A poll conducted by the Discovery Channel after the show found that nearly 75 percent of viewers believed Megalodon was still alive, indicating that the majority viewed the documentary as fact rather than fiction.

Artist’s rendering of a Megalodon, courtesy of Kevin Oedekoven.

The network has defended its programming, with executive producer Michael Sorenson claiming that, “[w]ith a whole week of Shark Week programming ahead of us, we wanted to explore the possibilities of Megalodon.” However, as explained by zoologist Stephen Wroe of the University of New South Wales in Australia, the real science behind the ancient shark has plenty of possibility. Wroe’s models indicate that Megalodon could exert up to 40,000 pounds of bite force, enough to destroy a small car. The shark is thought “to have used its massive jaw to bite the tails and flippers off large whales, effectively taking out their propulsion systems.” The teeth used to inflict this massive damage support Megalodon’s literal translation as “big tooth,” ranging from three to seven inches in size with sharp serrated edges.

With these sort of awe-inspiring, scientifically supported facts known about Megalodon, it seems unnecessary to create false excitement about the shark. The Discovery Channel has a unique position as “the world’s #1 nonfiction media company,” and its viewers trust the network to provide them with informative and entertaining content. Shark scientist David Schiffman has heard members of the public believe “because they saw it on the Discovery Channel, that Megalodons are real, and we have to launch a campaign to protect humans against them by killing sharks.” When science communication causes people to fear rather than to understand and value nature, it has failed in its most important goal.

Twitter Roundup – Daily Science Updates

Having newly acquired a smartphone, I can attest to the potential of these devices to be distracting. However, the ability to stay updated on the latest science news is a great benefit, and a number of scientists and science organizations (including this blog) have taken to Twitter as a means of communication. Here are ten of the most interesting, amusing, or informative feeds I follow on a daily basis.

Neil deGrasse Tyson – The popular astrophysicist provides a humorous but scientific perspective on current events, as exemplified by his recent spin on the Alex Rodriguez doping scanadal. Oh, and he’s met Superman.

Asteroid Watch – If an event like that which took out the dinosaurs is going to happen, NASA’s Near Earth Object Office will make sure you’re among the first to know.

What-If Numbers – This feed documents the research conducted by xkcd’s Randall Munroe as he prepares his weekly “What If” blog, reporting such unusual statistics as the total number of living teeth in the US (over 7 billion) and the combined length, in miles, of all living blue whales (120).

YA BOY BILL NYE – While the real Bill Nye does have a Twitter, it’s rarely as amusing as this over-the-top (and slightly NSFW) parody. Contained in the craziness are often some cool science facts, like the ability of turkeys to run 20 miles an hour.

Science Magazine – For a more serious take on the news of the day, there’s no more authoritative source than the feed of the world’s leading journal.

Adam Savage – The Mythbusters cohost provides a behind-the-scenes viewpoint on the popular TV series while also retweeting many of the more “spectacular” science pictures and videos on the web.

World Wildlife Fund – The conservation organization combines calls to “clicktivism” with fascinating tidbits about nature (and often stunning animal photos).

Joanna Manaster – This professor from my graduate alma mater provides a very accessible perspective on current biology and other science, often with a healthy dose of nerd culture thrown in.

Kevin Corbett – Any students would be advised to follow this feed, which focuses on the growth of technology use in higher education and the concept of “gamification,” where video games power learning and achievement.

Marion Nestle – Nestle, a professor at New York University, combines political and scientific news into a comprehensive picture of the agricultural and food issues facing the United States and the world at large.

Green Acres – Lawn Removal and Water in the Southwest

Writing this post in suburban Cincinnati, I am surrounded by the buzzing of sprinklers and lawnmowers under the summer sun. Every yard has its carpet of grass, requiring regular watering and constant cutting. In suburban Las Vegas, however, things are undoubtedly much quieter; the city has banned the planting of new turf in the front yards of single-family homes and the common areas of apartment buildings.

Vegas’s restrictions have emerged from concerns over the growing problem of water in the American Southwest. Nearly all of the region’s water resources come from the Colorado River, which stretches from its headwaters in the Rocky Mountains to the Gulf of California. Since the establishment of the Colorado River Compact in 1922, a series of regulations colloquially known as the “Law of the River” have allotted water to each of the seven states in the Colorado River Basin, controlled by a complex system of dams and canals. Yet as global climate change continues to increase the likelihood of drought conditions in the region, water supplies may not be able to meet the rates specified by the law.

The problems caused by lack of water are tied into other areas of the Southwest’s prosperity, from agriculture to electricity. For example, Arizona farmers use 77 percent of the state’s water resources, nearly all of it piped in along irrigation systems from the Colorado. The majority of agricultural water in the region is used to grow hay for animal feed, even though this crop provides the least value per acre-foot of water. The river’s flow is directly tied to the ability of massive hydroelectric projects like the Hoover Dam to produce power, but other electric producers depend on the river for cooling. Geothermal and coal plants are concerned that droughts could put them out of production, causing power outages across the Southwest.

Courtesy of wikihow.com

In light of these large-scale issues, reducing the water used for lawns and gardens may seem like a drop in the bucket, but when applied over the entire region, the savings become quite significant. Over the past ten years, Las Vegas’s program has reduced water use by over 9 billion gallons, and Los Angeles is sponsoring a lawn rebate scheme estimated to save 47 million gallons yearly. Monetary incentives have encouraged many homeowners to practice xeriscaping, the replacement of lawns with “regionally appropriate plants” that can tolerate low water conditions. Cacti and succulents are a far cry from the green fields one expects in the suburbs, but they may play a crucial role in ensuring that the Southwest’s thirst is met in the coming years.

Special Order – Lab-Cultured Meat

Fast-food giant McDonald’s has attracted a great deal of attention in the past few weeks for refusing to raise prices on their famous Big Mac hamburger in order to increase the wages of their workers. One wonders, then, what the corporation would think of a burger that cost $330,000. Such a sandwich was recently displayed (and consumed) in London, its hefty price tag justified by its unusual origins: the all-beef patty was derived entirely from lab-cultured tissue.

The first lab-grown burger. Courtesy of David Parry.

Mark Post, a professor of vascular physiology at Maastricht University in the Netherlands, is the man behind the meat. Post’s team harvested stem cells from the muscle tissue of a live cow, then placed these cells in a mixture of fetal calf serum and growth medium. By maintaining a close control on the nutrients available to the stem cells, the team ensured that they differentiated into muscle cells instead of the myriad of other possible cell types. As the cells grew and divided, they formed tiny muscle fibers, or myotubes, which the researchers stretched in the lab to simulate exercise. Approximately 20,000 of the half-inch long, twenty-fifth-inch diameter strips were combined to form the final burger, which the tasters judged as “close to meat” and “surprisingly crunchy.”

The process is certainly more difficult (and expensive, although the cost of the London burger was defrayed by Google cofounder Sergey Brin) than raising an actual cow, but proponents of lab-cultured meat emphasize a number of possible benefits. By bypassing the inefficiencies of energy transfer involved with feeding animals, as discussed in a previous article on this blog, Post estimates that his method can save 70 percent of the energy used in conventional meat production. A recent article published in the journal Environmental Science and Technology also projects radical reductions in the greenhouse gas emissions, land requirements and water use of meat production through the use of laboratory techniques. Even the animal rights organization PETA is supportive of the idea, emphasizing the millions of animals who could potentially be spared from slaughter and mistreatment.

Besides cost, a number of technical hurdles remain before cultured meat can be considered ready for supermarket shelves. Only muscle tissue can currently be produced by available methods, which is sufficient for a hamburger but not for a full-fledged sirloin or other cuts. Post’s team is hoping to produce fat and bone cells from culture in the months to come, but structuring them into a steak could take more work. The nutrient content of the meat has yet to be tested, and it is likely that it will need to be supplemented with iron and other minerals. From an ethical standpoint, meat culture using current methods still requires a donor animal for the initial stem cells. Other researchers are attempting to bypass this requirement by isolating embryonic stem cells, which can divide indefinitely, or by regressing skin cells into stem cells for differentiation into muscle. A guilt-free filet mingon may be indeed be a possibility in the years to come.