Check out this month's On the Web links, your connection to earth science friendly Web sites. The popular Geomedia feature is now available by topic.

Wikipedia v. Britannica: Reader beware
By the Numbers Print Exclusive
Cambrian Explosion Errors Indentified Web Exclusive

Books: Amazing ice: A review of Ice: The Nature, the History and the Uses of an Astonishing Substance

In one corner: Wikipedia, an upstart online encyclopedia established in 2001 as an “open source” site of information. In the other: Encyclopedia Britannica, the vaunted volumes of information that have been in print (and now on DVD-ROM as well as online) since 1768. The object: Determine which is more accurate, from the perspective of scientists reviewing either encyclopedia.

Reporters at the British journal Nature set out to assess the accuracy of select science entries in each encyclopedia — both cover everything from eggs to Einstein — that they considered basic to the fields the journal covers, from physics to psychology. The test consisted of a mix of anonymous and named reviewers whom the reporters considered appropriate specialists in their fields, based on seniority, experience and respect from their peers. Each reviewer compared entries from Wikipedia and Encyclopedia Britannica, without knowing which entry came from which encyclopedia. Tucked into the list of subjects sent to reviewers were several references that could be considered geological, the most geology-centered of which was “Cambrian Explosion.”

An anonymous reviewer docked both Wikipedia and Britannica for multiple offenses on their Cambrian Explosion articles. Mistakes ranged from incorrect geological time (Britannica used out-of-date dates for the beginning of the Cambrian, for example) to incorrect assertions regarding the fossil record (Wikipedia posted that only preserved creatures that develop from one or two layers of outer cells were known before the discovery of the Burgess Shale, completely ignoring long-known “triploblasts,” such as trilobites).

“The exercise revealed numerous errors in both encyclopaedias,” reporter Jim Giles wrote in Nature on Dec. 14, “but among 42 entries tested, the difference in accuracy was not particularly great: the average science entry in Wikipedia contained around four inaccuracies; Britannica, about three.”

However, Bruce Lieberman, a paleobiologist specializing in the Cambrian and a professor at the University of Kansas in Lawrence, noted that in the case of the Cambrian Explosion, some of the objections were merely nitpicky for Britannica (such as the dates), but the mistakes made in Wikipedia were more grievous (such as the trilobites omissions). “Most of the disagreements the reviewer had with Britannica had to do with interpretation, but the article always presented [the facts] as interpretation,” Lieberman says. Britannica put possibly disputable facts into context using phrases such as “now thought” or “various researchers recognize,” to indicate that research is ongoing; “Wikipedia never put in that context,” Lieberman says, “and it’s got some glaring errors.”

Having so many inaccuracies or outright false assertions perhaps should be somewhat unnerving to either encyclopedia’s users. Each encyclopedia touts the fact that they are peer-reviewed: Wikipedia by anyone, amateur and professional alike, and Britannica by professional editors and fact checkers. Wikipedia has more than 950,000 articles, while the DVD-ROM of Britannica contains more than 100,000 (according to Wikipedia). But, Lieberman says, the difference between a professional and volunteer corps may make the difference in accuracy of entries — even though he himself has acted as a volunteer reviewer for the Glossary of Geology (produced by the American Geological Institute, the publisher of Geotimes).

Part of the difference also comes with time taken to perform reviews and vigorous fact-checking by acknowledged leaders in a field. Some Wikipedians may be professionals, but they may not have the time to devote to fixing the free resource, and so mistakes creep in, Lieberman says.

“Are there tremendous amounts of damage being done with this?” Lieberman asks rhetorically. No, he says, but “when it comes to science,” inaccurate and easily accessible information, particularly online, “could lead to the spread of misinformation, and ultimately, that’s a pretty high price to pay.”

For example, with regard to evolution and intelligent design (the idea that complexity proves that a higher intellect created everything), readers have “no way of evaluating” information from off the Web, he says. “It may be just what gets hit by the browser they’re using. Science is not a popularity contest; data has to be the arbiter.”

Nature’s peer-review exercise may have bred a small bit of distrust for both Wikipedia and Britannica — and even for peer-review, which has been under attack most recently because of the stem-cell fabrications published in Science. But the peer-review system, Lieberman says, is the “best we’ve got,” despite its flaws. Nature’s comparison may be better seen as a reminder to readers to be somewhat skeptical — and to beware of any source!

 

Cambrian Explosion Errors Indentified In its comparison of error rates in Wikipedia and Encyclopedia Britannica entries, Nature picked a "reasonable spread" of topics from biology and physics to people and places. The blind review, in which volunteers selected to examine entries from each dictionary did not know which came from which, yielded a variety of responses and errors. For example, the reviewer of the entries for Cambrian Explosion noted that Britannica missed a lot of geological dates - such as the base of the Cambrian, which is 543 million years ago according to the newly revised international geologic time scale, not 540 million years ago. The anonymous reviewer also took umbrage with the encyclopedia's conclusions regarding oxygen and the development of calcium carbonate, noting that the "role of oxygen in [the] Cambrian explosion may well have been important, but it [the explosion] involved much more than the evolution of hard parts." The reviewer also keyed into a controversial topic, noting that a species that Britannica identified as a parasite is considered a scavenger by some paleobiologists - but that is still a topic to be debated. Regarding Wikipedia, similar though perhaps more grievous errors were identified by the anonymous reviewer, who pointed out that the entry got some fairly basic things wrong. One particularly misleading sentence reads that "the development of sexual reproduction increased the rate of evolutionary change" during the Snowball Earth time period - but sexual reproduction "almost certainly evolved long before," the reviewer wrote. The entry also cites trace fossils that give evidence of complex life forms 600 million years ago, but the reviewer says that "no convincing trace fossils occur at 600 Ma (or earlier)." Naomi Lubick ERRORS IDENTIFIED: ENCYCLOPEDIA BRITANNICA "Numerically dominant" [and in passing note this is not defined: species?, individuals?] forms in the Cambrian are arthropods and sponges; neither phylum "became extinct". The onychophoran Aysheaia may have grazed/scavenged sponges, but it is not a parasite in any generally accepted sense. The Ordovician extinctions were not at the "end" of the Period, but in the Ashgill. Geological dates: base of Cambrian is 543, not 540 Geological dates: base of Ordovician is at 488, not 505 Geological dates: base of Silurian is 444, not 438, (if we take early Silurian as Llandovery then its time span is 444-428) Geological dates: 421 is definitely Ludow. Evolution of hard parts at beginning of Cambrian involved much more than development of calcium carbonate. Role of oxygen in Cambrian explosion may well have been important, but it involved much more than the evolution of hard parts. Many suspension feeders, e.g. bryozoans, brachiopods, radiated in Ordovician, not Silurian. ERRORS IDENTIFIED: WIKIPEDIA "Prior to the discovery of the Burgess Shale ….". Absolutely wrong! The existing fossil record clearly demonstrated the existence of triploblasts, e.g. trilobites. Diploblasts are much more complex, and to write "every cell …[is]… in contact with its watery mineral-rich environment" is basically wrong. Diploblastic/triploblastic; actually refers to germ layers, not "layers" in adult animal. Diploblasts have "internal organs" e.g. gonads. Evidence for Ediacaran triploblasts was available long before discovery of phosphatized embryos. Ediacaran fauna is known to span c. 565-540 Ma, i.e. much more than 10 Ma before Precambrian-Cambrian boundary." "Sexual reproduction" almost certainly evolved long before "Snowball Earth". Ediacaran faunas are no older than c. 570 Ma; no convincing trace fossils occur at 600 Ma (or earlier) Cloudina is misspelt. Cloudina is effectively Ediacaran in age, and is not know to extend into the Tommotian. Cambrian fish "unlike any fish alive today": highly misleading. Back to top

Ice: The Nature, the History and the Uses of an Astonishing Substance by Mariana Gosnell. Alfred A. Knopf, 2005. ISBN 0 6794 2608 6 Hardback, $30.00.

Mariana Gosnell is a self-professed pagophile — a lover of ice. Her obsession is our pleasure as she shares it with us in her new book, Ice: The Nature, the History, and the Uses of This Astonishing Substance. This comprehensive treatment of ice at a very readable level engages us in a fascinating and enlightening conversation. As befits her chilly subject, it would be good to read this book while wrapped in a blanket in front of the fireplace, sipping a hot toddy, becoming engrossed in Gosnell’s exposé of absorbing facts about ice.

Those who think they know all there is worth knowing about ice are in for a pleasant surprise. Whether your familiarity with ice is casual and seasonal or as a trained glaciologist, there is much to learn from Gosnell’s treasure trove of icy information. After reading this book, you can be assured that you will never look at ice the same way and will be well-stocked with a mountain of fascinating facts about this surprisingly essential element of our world — the impact it has on us, the landscape around us, the animals and plants we enjoy, and even some of the planets and moons in our cosmos.

Gosnell turns on its head the notion that ice’s importance is limited to the remote high latitudes and high elevations. She reminds us that we likely owe our very existence on this planet to ice delivered to primordial Earth as the young planet collided with icy comets zipping through interstellar space. Our dependence continues today, as the early uses of ice for ancestral conveniences such as refrigeration have been refined to more effective food preservation methods such as freeze-drying. Gosnell even extends her view into artistic and fanciful realms, discussing the history and nuances of preparing the beautiful ice sculptures that frequently adorn large banquet tables.

Her description is remarkable for both its thoroughness and the large number of ice experts she brings into her tale, such as prominent glaciologists who study the effect that ice in its frigid polar environment has on the rest of the planet. We are also introduced to paleoclimatologists who unlock the secrets of past conditions on the planet by reading the sealed atmospheric record trapped in air bubbles and carefully extracted in sterile modern laboratories. And we hear from biologists who investigate the variety of coping mechanisms polar flora and fauna have developed to not only survive, but also to thrive, in extreme cold and extended darkness. Gosnell lets these experts speak for themselves and admirably captures their passion for the subject in ways that illuminate modern research on ice.

Gosnell, a journalist, prepared exhaustively for her writing task by traveling to most of the places about which she writes, to both speak directly with the researchers and to observe with her own eyes. This personal approach works beautifully as she adopts the persona of an “on-the-scene reporter.” She reports from the bridge of an icebreaker as it violently smashes it way through meters-thick ice; camped in a survival shelter in the middle of a howling Antarctic blizzard; and bundled against the penetrating chill of a deep-storage freezer that contains priceless sections of ice cores recovered from ice sheets around the world.

I have not found another book that describes the full breadth of ice and its impact on this (and other) worlds in such a comfortable reading style. The book’s 560 pages contain enough information to allow many journeys of discovery. While not richly illustrated, it contains some photos that are not to be missed of early attempts to use or tame ice. The extensive index and organization of the book also can guide the reader to a specific area or back to a particularly endearing fact or interview.

Don’t be surprised to discover that even before the end of this wonderful book that you, too, have become a pagophile.

Geotimes Home | AGI Home | Information Services | Geoscience Education | Public Policy | Programs | Publications | Careers © 2024 American Geological Institute. All rights reserved. Any copying, redistribution or retransmission of any of the contents of this service without the express written consent of the American Geological Institute is expressly prohibited. For all electronic copyright requests, visit: http://www.copyright.com/ccc/do/showConfigurator?WT.mc_id=PubLink