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Electronic Letters are short, timely responses to selected articles published in Science. Recently published E-Letters appear below; for guidelines and instructions on submitting E-Letters, see our E-Letters Home Page.

E-Letter responses published in the past 60 days:

Read E-Letter responses published in the last 1, 2, 3, 4, 5, 6, 7, 14, 21 days

17 E-Letter responses published for 13 different topic sources.

Articles    E-Letter Responses
Jump to E-Letter responses for citation
letters:
Rewarding Reviewers
Metz (7 March 2008) [Full text] [PDF]
Jump to E-Letter Include Reviewing Into the Single Researcher Impact Factor
Gianluca Castelnuovo   (9 May 2008)
Jump to E-Letter Reviewers Deserve It
Jochen F. Staiger   (8 May 2008)
 Read every E-Letter response to this article

Jump to E-Letter responses for citation
reports:
Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change
Searchinger et al. (29 February 2008) [Abstract] [Full text] [PDF]
Jump to E-Letter Food, Land Use Changes, and Biofuels
Steven A. Kolmes   (25 March 2008)
 Read every E-Letter response to this article

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n-focus:
EVOLUTION: Crossing the Divide
Couzin (22 February 2008) [Full text] [PDF]
Jump to E-Letter Evolving Universe
Virginia A. Dell   (25 March 2008)
 Read every E-Letter response to this article

Jump to E-Letter responses for citation
reports:
Effects of Predator Hunting Mode on Grassland Ecosystem Function
Schmitz (15 February 2008) [Abstract] [Full text] [PDF]
Jump to E-Letter Response to J. A. Newman's E-Letter
Oswald J. Schmitz   (24 April 2008)
Jump to E-Letter A Failure to Test the Hypothesis of Interest
Jonathan A. Newman   (24 April 2008)
 Read every E-Letter response to this article

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reports:
A Heme Export Protein Is Required for Red Blood Cell Differentiation and Iron Homeostasis
Keel et al. (8 February 2008) [Abstract] [Full text] [PDF]
Jump to E-Letter Heme-Controlled Protein Synthesis
Heikki Savolainen   (25 March 2008)
 Read every E-Letter response to this article

Jump to E-Letter responses for citation
r-articles:
Natural Streams and the Legacy of Water-Powered Mills
Walter and Merritts (18 January 2008) [Abstract] [Full text] [PDF]
Jump to E-Letter R. C. Walter and D. J. Merritts' Response to K. D. Johnson's E-Letter Comment
Robert C. Walter, et al.   (25 March 2008)
Jump to E-Letter Dammed, You Say...
Keith D. Johnson   (18 March 2008)
 Read every E-Letter response to this article

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special/news:
NEWS: Untangling the Celestial Strings
Cho (4 January 2008) [Full text] [PDF]
Jump to E-Letter Poetic Justice
Robert W. Greenwood   (20 March 2008)
 Read every E-Letter response to this article

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brevia:
Theory of Mind Is Independent of Episodic Memory
Rosenbaum et al. (23 November 2007) [Abstract] [Full text] [PDF]
Jump to E-Letter Response to N. Reinhold and H. J. Markowitsch's E-Letter
R. Shayna Rosenbaum   (24 April 2008)
Jump to E-Letter Theory of Mind and the Sense of Self
Nadine Reinhold, et al.   (10 April 2008)
 Read every E-Letter response to this article

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n-focus:
COSMOLOGY: A Singular Conundrum: How Odd Is Our Universe?
Cho (28 September 2007) [Full text] [PDF]
Jump to E-Letter Oddity of WMAP Spherical Harmonics
Dilip G. Banhatti   (20 March 2008)
 Read every E-Letter response to this article

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n-week:
ENGINEERING: Pollution Slows China's Canal Project
Hao (28 September 2007) [Full text] [PDF]
Jump to E-Letter Chinese Water Canal Project
Shaopeng Huang   (18 March 2008)
 Read every E-Letter response to this article

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n-week:
MARINE GEOLOGY: Support Is Drying Up for Noah's Flood Filling the Black Sea
Kerr (17 August 2007) [Full text] [PDF]
Jump to E-Letter Update on Black Sea Research
Gilles Lericolais   (20 March 2008)
 Read every E-Letter response to this article

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r-articles:
The Product Space Conditions the Development of Nations
Hidalgo et al. (27 July 2007) [Abstract] [Full text] [PDF]
Jump to E-Letter Access to Product Space and Transformations Study Data
Cesar A. Hidalgo   (30 April 2008)
 Read every E-Letter response to this article

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compviewpoint:
SCIENCE'S RESPONSE:
Is a Government Archive the Best Option?
Editors (23 March 2001) [Full text]
Jump to E-Letter The Copyright Laws Are Important
James W. Farr   (9 May 2008)
 Read every E-Letter response to this article
letters:
Rewarding Reviewers
Metz (7 March 2008) [Full text] [PDF]
Rewarding Reviewers
Include Reviewing Into the Single Researcher Impact Factor
9 May 2008
 Next E-Letter Top
Gianluca Castelnuovo,
Professor of Psychology and Researcher in Clinical Psychology
Istituto Auxologico Italiano IRCCS, Psychology Research Laboratory, 28824, Italy

Respond to this E-Letter:
Re: Include Reviewing Into the Single Researcher Impact Factor

As a member of two editorial boards and having reviewed many manuscripts over the years, I resonate with the Letters by W. F. Perrin, R. S. Zucker ("In search of peer reviewers, 4 January 2008, p. 32), M. A. Metz and G. Marchionini ("Rewarding reviewers," 7 March 2008, p. 1335) and I propose to better consider the peer reviewer responsibilities, merits and scientific contributions. Writing and finalizing an article is a very complex process where reviewers can usually offer a valid and crucial scientific contribution that can make an article ready to be published and appreciated in the scientific community.

In order to make peer-reviewers more compliant in their fundamental role for the improvement of science, according to Metz's solutions (such as "count of average manuscript reviews per year on applicant CVs", p. 1335) and to the up-to-date scientific debate about how to find a better index than impact factor (IF) to measure the single scientist's impact factor (1, 2), one possible solution is to create a new index, such as the Single Researcher Impact Factor (SRIF) that can take into account number and quality of the traditional publications and of the other activities usually associated with being a researcher, such as reviewing manuscripts. Some experimental versions of this new index are under evaluation in Economics (3), Psychology (4) and Medicine (5, 6). By replacing the journal-centered IF with a single researcher-centered IF, that can include reviewing activity too, the evaluation of individual scientific impact in the community will be more accurate and could motivate researchers, overall young ones, in reviewing without frustration.

Gianluca Castelnuovo

Istituto Auxologico Italiano IRCCS, Psychology Research Laboratory, 28824, Italy.

References

1. T. Gracza, I. Somoskovi, Orv. Hetil., 148 (18), 849 (2007).

2. G. Castelnuovo, Are there good alternatives for the “Impact Factor” algorithm? Response to H. Brown, How impact factors changed medical publishing—and science, BMJ, 2007; http://www.bmj.com/cgi/eletters/334/7593/561#162628.

3. P. Tucci, S. Fontani, S. Ferrini, L’R-factor: un nuovo modo di valutare la ricerca scientifica, Quaderni del Dipartimento di Economia Politica, 527, 1 (2008).

4. E. Molinari, G. Castelnuovo, in Psicologia Clinica: Dialoghi e Confronti, E. Molinari, A. Labella Eds. (Springer, 2007), pp. 203-215.

5. A. B. Adams, D. Simonson, Respiratory Care 49 (3), 276 (2004).

6. P. M. Ironside, J. Gerontol. Nurs., 33 (6), 3 (2007).

Rewarding Reviewers
Reviewers Deserve It
8 May 2008
Previous E-Letter Next E-Letter Top
Jochen F. Staiger,
Professor of Cell Biology
University of Freiburg, 79085 Freiburg, Germany

Respond to this E-Letter:
Re: Reviewers Deserve It

The Letter by M. A. Metz ("Rewarding reviewers," 7 March 2008, p. 1335) speaks to my heart!

Since the advent of electronic submissions and reviewing of manuscripts, very many journals do not inform the reviewers about the outcome of their efforts, and we have to find out for ourselves by logging in at Web sites.

Improvements like those suggested here will certainly increase the willingness and effort taken by reviewers to serve the scientific community.

Jochen F. Staiger,

Department of Cell Biology, University of Freiburg, 79085 Freiburg, Germany.

reports:
Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change
Searchinger et al. (29 February 2008) [Abstract] [Full text] [PDF]
Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions...
Food, Land Use Changes, and Biofuels
25 March 2008
Previous E-Letter Next E-Letter Top
Steven A. Kolmes,
Professor
University of Portland

Respond to this E-Letter:
Re: Food, Land Use Changes, and Biofuels

T. Searchinger et al. [as well as Fargione et al. (1)] make the case that whether biofuel production has a net greenhouse gas benefit depends on land use changes as large new areas are converted to agricultural uses and a carbon debt is incurred. Alternatively, dietary changes in the United States could free vast areas for biofuel production without converting more land to agricultural use. Beef requires 13 kg of grain and 30 kg of forage per kg of meat produced; broiler chickens, 2.3 kg of grain per kg of meat. Additionally, beef production requires 57 kcal of fossil fuel for each kcal of food gained, while broiler chickens have a 4:1 ratio (2). The FAO estimates cattle rearing and processing accounts for 18% of global greenhouse gas emissions (3). The U.S. grows slightly under 40 million hectares of corn and roughly 25 million hectares of soybeans (4). A little over half the corn we grow goes into animal feed (5). Over half the soybeans grown in the U.S. are crushed for soymeal and oil, and approximately 90% of the soymeal produced goes into livestock feed for meat (6). A lacto-ovo-vegetarian diet (dairy, eggs, plants) also requires animal feed, but about half as much as a meat-heavy American diet (2).

If the U.S. consumed less red meat, millions of hectares in corn or soy production could be used for ethanol or biodiesel, with no undesirable land use alterations and hence no additional carbon debt. Fossil fuel demand would also be reduced if we moved away from the 57:1 ratio mentioned above. Additionally, livestock produce methane, a potent greenhouse gas. Moderating our carnivory could therefore help reduce what are presently abnormally high atmospheric methane levels (7). We don’t need to wait for technological advances in lignocellulosic ethanol to make biofuel production an important component of atmospheric carbon reduction. We just need to eat as though we live on a finite planet.

Steven A. Kolmes

Environmental Studies Program, University of Portland, Portland, Oregon 97203, USA.

References

1. J. Fargione, J. Hill, D. Tilman, S. Polasky, P. Hawthorne, Science 319, 1235 (2008).

2. D. Pimentel, M. Pimentel, Am. J. Clinical Nutrition 78, 660S (2003).

3. H. Steinfeld et al., Livestock’s Long Shadow, Environmental Issues and Options, Food and Agriculture Organization of the United Nations, ISBN 978- 92-5-105571-1 (2006) (available at http://www.virtualcentre.org/en/library/key_pub/longshad/A0701E00.pdf).

4. National Agricultural Statistics Service, USDA, Report Released June 29, 2007 (available at http://www.usda.gov/nass/PUBS/TODAYRPT/acrg0607.txt).

5. E. Leibtag, Amberwaves (2008) (available at http://www.ers.usda.gov/AmberWaves/February08/Features/CornPrices.htm).

6. Soy Stats, 2007, available at http://www.soystats.com/2007/Default- frames.htm (Sponsored by the Illinois Soybean Association, Indiana Soybean Alliance, Minnesota Soybean Research & Promotion Council, North Dakota Soybean Council, Ohio Soybean Council, Iowa Soybean Association, South Dakota Soybean Research & Promotion Council, and the Kentucky Soybean Board.)

7. J. R. Petit et al., Nature 399, 429 (1999).

n-focus:
EVOLUTION: Crossing the Divide
Couzin (22 February 2008) [Full text] [PDF]
EVOLUTION: Crossing the Divide
Evolving Universe
25 March 2008
Previous E-Letter Next E-Letter Top
Virginia A. Dell,
Professor, Biology Department
Oklahoma School of Science and Mathematics

Respond to this E-Letter:
Re: Evolving Universe

To comment on the News Focus article ("Crossing the divide" by J. Couzin, 22 February 2008, p. 1034), perhaps one way to ease the trauma of separation from old ways of belief and the disapproval of family members is to consider that an all-powerful God surely is almighty and creative enough to create a universe that evolves. The concept of a Supreme Being who creates a living system in which variability is built in is much richer than the brief story in Genesis. I doubt however, that such an idea will be taken seriously by literal interpreters of the Bible.

The fact is that education of any kind can lead to disconnects from parents and family who just do not understand the need and the drive to learn more about the world around us. The discoveries made about the workings of our marvelous universe are the primary motivation for most scientists, religious or not. Godfrey has expanded his world; his family has not.

Virginia A. Dell

Biology Department, Oklahoma School of Science and Mathematics, Oklahoma City, OK 73104, USA.

reports:
Effects of Predator Hunting Mode on Grassland Ecosystem Function
Schmitz (15 February 2008) [Abstract] [Full text] [PDF]
Effects of Predator Hunting Mode on Grassland Ecosystem Function
Response to J. A. Newman's E-Letter
24 April 2008
Previous E-Letter Next E-Letter Top
Oswald J. Schmitz
Department of Forestry and Environmental Studies, Yale University, New Haven, CT 06511, USA

Respond to this E-Letter:
Re: Response to J. A. Newman's E-Letter

As elaborated in Schmitz (1), the study follows from the general insight derived from an empirical synthesis of a broad range of predator taxa (2) that the nature of predators' direct effects on their prey and indirect effects on the abundance and composition of the prey’s resources is related to predator hunting mode. That synthesis was motivated by natural history observations in my own particular system (3) that hunting mode differences of Pisaurina mira and Phidippus rimator might explain differences in patterns at the plant community level. The current study takes the next step by evaluating whether earlier insights (2) can be extended to explain ecosystem level functions.

I agree with Newman that theoretically it would be highly desirable to replicate hunting mode in a single study. However, the practical reality is that my study system, and perhaps many others, is constrained by the number of predator species within the community that have different hunting modes. In my system, the sit-and-wait mode is represented by just a single species. The implication of Newman’s argument that we can only conduct such studies within species-rich assemblages, is itself a kind of bias that will be counterproductive to the general ecological scientific goal of having experiments on the role of predator hunting mode carried out in many kinds of systems. After all, it is replication among many kinds of systems that is likely to lead to the robust conclusions we seek in trying to understand how community composition influences the functioning of ecosystems (4).

Oswald J. Schmitz

Department of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven, CT 06511.

1. O. J. Schmitz, Science 319, 952 (2008).

2. O. J. Schmitz, in Ecology of Predator-Prey Interactions, P. Barbosa, I. Castellanos, Eds. (Oxford Univ. Press, Oxon, 2005), pp. 256–278.

3. O. J. Schmitz, K. B. Suttle, Ecology 82, 2072 (2001).

4. S. Naeem, Science 319, 913 (2008).

Effects of Predator Hunting Mode on Grassland Ecosystem Function
A Failure to Test the Hypothesis of Interest
24 April 2008
Previous E-Letter Next E-Letter Top
Jonathan A. Newman,
Professor
University of Guelph, Guelph, ON , Canada

Respond to this E-Letter:
Re: A Failure to Test the Hypothesis of Interest

O. J. Schmitz (Reports, Effects of predator hunting mode on grassland ecosystem function, 15 February 2008, p. 952) attempts to test the hypothesis that "differences in foraging modes alter key ecosystem functions." While his experimental results are very interesting, I suggest that his experiment does not test the hypothesis of interest. His experiment only tests the hypothesis that the different predators, Pisaurina mira and Phidippus rimator, cause differences in key ecosystem functions. And I accept that Schmitz has admirably demonstrated that result.

To properly test the hypothesis about hunting mode, one would have to replicate "hunting mode" with a (preferably random) sample of predators that differ by hunting mode. As it is, Schmitz is cherry-picking one particular difference between the two predators (hunting mode) and attributing the results to that particular difference. Yet these two species undoubtedly differ in many more subtle characteristics besides their obvious difference in hunting mode. Any of these more subtle differences could potentially be responsible for the results. Suppose, for the sake of arguement, that the grasshoppers react not to the differences in foraging mode, but to differences between the two predators in their odor. Should the title of the paper then be: "Effects of Predator Odor on Grassland Ecosystem Function"?

We must remind ourselves that evidence consistent with a hypothesis does not constitute a test of that hypothesis. Schmitz's results are certainly consistent with the hypothesis that "differences in foraging modes alter key ecosystem functions" but they are not a test of that hypothesis.

Jonathan A Newman

University of Guelph, Guelph, ON N1G 2W1, Canada.

reports:
A Heme Export Protein Is Required for Red Blood Cell Differentiation and Iron Homeostasis
Keel et al. (8 February 2008) [Abstract] [Full text] [PDF]
A Heme Export Protein Is Required for Red Blood Cell Differentiation and Iron Homeostasis
Heme-Controlled Protein Synthesis
25 March 2008
Previous E-Letter Next E-Letter Top
Heikki Savolainen,
Professor
Department of Occupational Safety and Health, Tampere, Finland

Respond to this E-Letter:
Re: Heme-Controlled Protein Synthesis

In regard to S. B. Keel et al.’s Report ("A heme export protein is required for red blood cell differentiation and iron homeostasis," 8 February 2008, p. 825), the incorporation of freshly synthesized heme in the hemoprotein molecules is only one of its many regulatory roles. It also seems to restart protein synthesis in rat circulating reticulocytes after a histotoxic insult (1). This is mediated by a heme-stabilized translational inhibitor (2). The system depends on a redox cycle catalyzed by thioredoxin (1). The heme iron must be in a ferrous state and free iron ions are not substrates. Therefore, it seems that using heme as an independent therapeutic agent opens up very promising vistas.

Heikki Savolainen

Department of Occupational Safety and Health, Tampere, Finland.

References

1. H. Savolainen et al., Res. Commun. Chem. Path Pharmacol. 50, 245 (1985).

2. C. Palomo et al. Arch. Biochem. Biophys. 239, 497 (1985).

r-articles:
Natural Streams and the Legacy of Water-Powered Mills
Walter and Merritts (18 January 2008) [Abstract] [Full text] [PDF]
Natural Streams and the Legacy of Water-Powered Mills
R. C. Walter and D. J. Merritts' Response to K. D. Johnson's E-Letter Comment
25 March 2008
Previous E-Letter Next E-Letter Top
Robert C. Walter
Department of Earth and Environment, Franklin and Marshall College, Lancaster, PA 17604, USA,
Dorothy J. Merritts

Respond to this E-Letter:
Re: R. C. Walter and D. J. Merritts' Response to K. D. Johnson's E-Letter Comment

K. D. Johnson raises an excellent point about the impact of beavers on pre-settlement streams. We did not, however, overlook the impact of these animals. In Walter and Merritts [(1), p. 302] we state: "This regional network of small streams and low, vegetated islands within the flood zone was probably impacted heavily by beaver dams and small ponds…" [c.f., (2)]. We intended to say more on this subject, but other topics took precedence. We welcome this opportunity to elaborate on the geomorphic impacts of beaver.

The online article referred to by Johnson (3) is a cogent summary of some of the classic work on modern beaver populations. This article and references cited therein demonstrate that valleys impacted by beaver are quite similar to our description of pre-settlement waterways in the mid-Atlantic region of the United States, as based on geological, geochemical, and geomorphological analyses of the ubiquitous, buried pre-settlement wetland (hydric soil) (1).

Regarding observations of modern beaver ecology, Pollack et al. (4) infer that "beaver dams created stream systems with slow, deep water and floodplain wetlands dominated by emergent vegetation and shrubs." Hemenway states: "A natural North American stream is not a single, deeply eroded gully, but a series of broad pools… stitched together by short stretches of shallow, braided channels" (3). Note the term "braided" has a specific meaning in geomorphology and is associated with high-energy streams with high sediment loads; the systems as described by us and presumably by Hemenway—which are low gradient streams with low pre-settlement sediment loads—are more appropriately referred to as "anabranching" (5).

Compare these statements to our description of pre-settlement stream systems in the mid-Atlantic: "Valley bottoms along eastern streams were characterized by laterally extensive, wetland-dominated systems of forested meadows with stable vegetated islands and multiple small channels during the Holocene… In particular, logjams blocked channels and led to the formation of side channels and floodplain sloughs, producing multiple anabranching channels and riverine wetlands that are in stark contrast to the large, single channels that exist in these streams today" (1). This convergence of ecological and geological perspectives underscores the important link between beaver activity and the shape, function, and stability of stream systems.

There is substantial added value to beaver habitats in streams. Beaver ponds trap sediments, create organic-rich wetlands, store carbon, filter nutrients, increase biodiversity, reduce flow velocities, and recharge groundwater (2, 4, 6–8).

Prior to European settlement, beaver were abundant and had considerable geomorphic impact on stream valleys in the mid-Atlantic Piedmont, but there was essentially no sediment being shed from the forested upland hill slopes [long-term erosion rates of < 0.006 cm/yr, (9, 10)] until European settlers began clearing the land in the late 17th and early 18th centuries (11, 12). Without that sediment supply, there was little to fill in beaver ponds except organic matter. In mid-Atlantic stream valleys, the pre-settlement hydric soil averages about 30 cm thick, and formed over the last ~10,000 years (1). In contrast, post-settlement alluvium averages about 2.5 m thick and formed within the last 300 years over a time span of about 150 years. The pre-settlement sediment accumulation rates in valley bottoms were low (~0.003 cm/yr) and consistent with the long-term geological erosion rates, compared with the unusually high post-settlement accumulation rates (~1.7 cm/yr).

The construction of numerous small beaver dams helped create the anabranching stream networks in the mid-Atlantic region during pre-settlement times, and beaver were an important factor in creating the pervasive wetlands that are now buried beneath thick stacks of post-settlement mud. Should beaver be reintroduced into mid-Atlantic streams, or can humans be as effective as beaver in engineering and adding value to streams?

Robert C. Walter and Dorothy J. Merritts

Department of Earth and Environment, Franklin and Marshall College, Lancaster, PA 17604, USA.

References

1. R. C. Walter, D. J. Merritts, Science 319, 299 (2008).

2. D. R. Butler, G. P. Malanson, Geomorphology 71, 48 (2005).

3. T. Hemenway, Permaculture Activist 47, Summer 2002; http://www.permacultureactivist.net/articles/Beavers.htm.

4. M. M. Pollock, M. Heim, D. Werner, Am. Fish Soc. Symp. 37, 213 (2003).

5. G. C. Nansen, J. C. Croke, Geomorphology, 4, 459 (1992).

6. R. L. Ives, Journal of Geomorphology 5, 191 (1942).

7. R. J. Naiman, C. A. Johnston, J. C. Kelley, BioScience 38, 753 (1998).

8. J. P. Wright, C. G. Jones, A. S. Flecker, Oecologia 132, 96 (2002).

9. M. J. Pavich, Appalachian Geomorphology, T. W. Gardner and W. D. Sevon, Eds. (Elsevier, Amsterdam, 1989), pp.181-196.

10. Hancock and Kirwan, Geology 35, 89 (2007).

11. G. S. Brush, Limnology and Oceanography 34, 1235 (1989).

12. W. B. Hilgartner, G. S. Brush, Holocene 16, 1 (2006).

Natural Streams and the Legacy of Water-Powered Mills
Dammed, You Say...
18 March 2008
Previous E-Letter Next E-Letter Top
Keith D. Johnson,
permaculture designer / teacher / consultant / associate editor
Permaculture Activist Magazine

Respond to this E-Letter:
Re: Dammed, You Say...

When R. C. Walter and D. J. Merritts were researching their article (Research Article, "Natural streams and the legacy of water-powered mills," 18 January 2008, p. 299) it seems that they may have overlooked some landscape patterns which preceded those established by settlers and were caused by those supreme hydrological engineers, beavers.

These animals, estimated to number 100 to 400 million before being made into hats for Europeans, built as many as 15 dams per mile stitched together by short stretches of shallow, braided channels. Their impact on sediment and organics impoundment, groundwater recharge via infiltration, and complex habitat creation, as well as other ecological impacts seems, ironically, similar (though arguably superior) to that of the settlers who followed with their own dams. Even more ironic, those same settlers never even saw, or accounted for, the extensive earth and waterworks since the beavers were mostly trapped out before their arrival.

An article written by Toby Hemenway (1) explores the complex ecological transformations performed by these hardy and handy mammals.

Taking beavers into account may not change Walter and Merritts' conclusions about the natural form of streams, but their impacts need to be factored into the equation.

Keith D Johnson,

Associate Editor, Permaculture Activist Magazine

Reference

1. T. Hemenway, Permaculture Activist 47, Summer 2002; http://www.permacultureactivist.net/articles/Beavers.htm.

special/news:
NEWS: Untangling the Celestial Strings
Cho (4 January 2008) [Full text] [PDF]
NEWS: Untangling the Celestial Strings
Poetic Justice
20 March 2008
Previous E-Letter Next E-Letter Top
Robert W. Greenwood,
Physician

Respond to this E-Letter:
Re: Poetic Justice

I wonder if the authors are familiar with a fragment of poetry, a portion of a verse in the poem "The Mistress of Vision" by Francis Thompson, that I think remarkably encapsulates the idea of the dark-matter web:

All things by immortal power,

Near and far

Hiddenly

To each other link-ed are,

That thou canst not stir a flower

Without troubling of a star.

Robert W. Greenwood

brevia:
Theory of Mind Is Independent of Episodic Memory
Rosenbaum et al. (23 November 2007) [Abstract] [Full text] [PDF]
Theory of Mind Is Independent of Episodic Memory
Response to N. Reinhold and H. J. Markowitsch's E-Letter
24 April 2008
Previous E-Letter Next E-Letter Top
R. Shayna Rosenbaum
Department of Psychology, York University, 4700 Keele Street, Toronto, ON M3J 1P3, Canada

Respond to this E-Letter:
Re: Response to N. Reinhold and H. J. Markowitsch's E-Letter

My colleagues and I showed that episodic memory (1) is not necessary for theory of mind (ToM) by demonstrating intact ToM in individuals with episodic memory loss following medial temporal lobe damage or disconnection [i.e., organic amnesia (2)]. Reinhold and Markowitsch propose that this issue may be better addressed by studying individuals with functional retrograde amnesia (RA). I agree that both types of amnesic patients do not offer the same sort of insight into understanding the relationship between episodic memory and ToM, though not for the reasons cited by Reinhold and Markowitsch. Functional RA refers to memory disturbance of psychological origin characterized by focal loss of episodic and/or semantic information acquired prior to amnesia onset (3, 4). Importantly, it often occurs in individuals with an extensive psychiatric history that predates or accompanies their amnesic episode (5). Thus, it is difficult to decipher if the reported inability of these individuals to infer other people’s thoughts and feelings (6, 7) is due to faulty episodic memory processes, or to some other aspect of personality or cognitive function, semantic memory or otherwise, that is simultaneously altered. Nevertheless, it is important to clarify that the claim in our paper is that episodic memory is not needed for ToM as measured by a range of widely accepted ToM tests (8). Our demonstration of intact ToM in individuals with complete impairment to episodic memory (9) is sufficient to support this claim, irrespective of etiology and time of testing since RA onset. Like Reinhold and Markowitsch, we commented in our paper that the individuals that we tested are likely using a cognitive system in place of episodic memory to sustain ToM. We further suggested semantic memory as a candidate system, and this was intended to include self-identity and other personal knowledge, though additional investigation is needed.

R. Shayna Rosenbaum

Department of Psychology, York University, Rotman Research Institute, Baycrest, 4700 Keele Street, Toronto, ON M3J 1P3, Canada.

References

1. E. Tulving, Annu. Rev. Psychol. 53, 1 (2002).

2. R. S. Rosenbaum, D. T. Stuss, B. Levine, E. Tulving, Science 318, 1257 (2007).

3. D. L. Schacter, P. L. Wang, E. Tulving, M. Freedman, Neuropsychologia 20, 523 (1982).

4. M. D. Kopelman, Cogn. Neuropsychol. 17, 585 (2000).

5. H. J. Markowitsch, Neuroimage 20, S132 (2003).

6. E. Fujiwara et al., Cortex (in press).

7. N. Reinhold, H. J. Markowitsch, J. Neuropsychol. 1, 53 (2007).

8. R. S. Rosenbaum, D. T. Stuss, B. Levine, E. Tulving, Science 318, 1257 (2007).

9. R. S. Rosenbaum et al., Neuropsychologia 43, 989 (2005).

Theory of Mind Is Independent of Episodic Memory
Theory of Mind and the Sense of Self
10 April 2008
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Nadine Reinhold
Department of Physiological Psychology, University of Bielefeld, Bielefeld, 33615, Germany,
Hans J. Markowitsch

Respond to this E-Letter:
Re: Theory of Mind and the Sense of Self

R. S. Rosenbaum et al. argue that the ability to infer other people's current mental states is independent of a well-functioning episodic memory system (Brevia, "Theory of mind is independent of episodic memory," 23 November 2007, p. 1257). The authors also extend their findings to an independency of autonoetic consciousness and Theory of Mind (ToM) abilities. They rest this extension on Tulving's definition of (1) episodic memory as the conjunction of three different concepts: self, autonoetic awareness, and subjective time. ToM, on the other hand, is strongly connected with the concepts of self and autonoetic awareness (2, 3). Although the presented results appear convincing, they have some limitations. Both patients presented by Rosenbaum et al. were tested long after the onset of their retrograde amnesia. Patients with psychogenic or functional retrograde amnesia investigated only 2 to 8 months after their amnesia onset are clearly impaired in ToM-tasks (4, 5). In ontogenetic development ToM abilities emerge at roughly the same time, but in close interaction with the development of episodic memory. We therefore propose that although both abilities overlap in their functions as well as in their neural correlates, they might be impaired independently. We suggest that the self as a core feature of episodic (autobiographical) memory and ToM abilities is essential for both processes—the emergence of autobiographical memories as well as for building up and strengthening the capability to infer other people's mental states (6). After disruption of the episodic memory system, other memory systems may, over time, replace the need to rely on the episodic memory system for ToM abilities, leading to restitution or substitution processes of ToM functions, similarly, as observed for other mental functions following brain damage.

Nadine Reinhold and Hans J. Markowitsch

Department of Physiological Psychology, University of Bielefeld, Universitaetsstr. 25, Bielefeld, 33615, GERMANY.

References

1. E. Tulving, Annu. Rev. Psychol. 53, 1 (2002).

2. L. Q. Uddin, M. Iacoboni, C. Lange, J. P. Keenan, Trends Cogn. Sci. 11, 153 (2007).

3. Y. Moriguchi et al., Neuroimage 32, 1472 (2006).

4. E. Fujiwara et al., Cortex (in press).

5. N. Reinhold, H. J. Markowitsch, J. Neuropsychol. 1, 53 (2007).

6. D. Hassabis, E. A. Maguire, Trends Cogn. Sci. 11, 299 (2007).

n-focus:
COSMOLOGY: A Singular Conundrum: How Odd Is Our Universe?
Cho (28 September 2007) [Full text] [PDF]
COSMOLOGY: A Singular Conundrum: How Odd Is Our Universe?
Oddity of WMAP Spherical Harmonics
20 March 2008
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Dilip G. Banhatti,
Research and teaching
Madurai-Kamaraj University, Madurai 625021, India

Respond to this E-Letter:
Re: Oddity of WMAP Spherical Harmonics

The systematically arranged multipoles surely indicate local matter-energy distribution, especially relative to the Milky Way Plane, which must be subtracted for any such reduction (News Focus by A. Cho, "A singular conundrum: How odd is our universe?", 28 September 2008, p. 1848). So also must telescope surroundings, in the form of host satellite orientation and orbit relative to Earth, be taken into account. Connection between these two points is provided by the orientation of the ecliptic relative to galactic plane. Our solar system's location in our home arm of the Milky Way spiral structure may also be relevant. Only after these instrumental and local (i.e., solar system and galactic) effects are factored in, one needs to go further out into the Local Group (Andromeda, Large and Small Magellanic Clouds, other members like Leos, and so on). If another satellite telescope with a significantly different orbit and/or location gives differently arranged multipoles, these will indicate which are the instrumental and local environmental effects.

Dilip G. Banhatti,

Madurai-Kamaraj University, Madurai 625021, India.

n-week:
ENGINEERING: Pollution Slows China's Canal Project
Hao (28 September 2007) [Full text] [PDF]
ENGINEERING: Pollution Slows China's Canal Project
Chinese Water Canal Project
18 March 2008
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Shaopeng Huang
Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109–1005, USA

Respond to this E-Letter:
Re: Chinese Water Canal Project

The Chinese South-to-North Water Diversion Project is a landscape-altering megaproject to bring water from the Yangtze River, the fourth largest river in the world, to the aid of the country’s arid north. The project has long been surrounded by debates over its social, economic, and environmental consequences. In the News of the Week story “Pollution slows China’s canal project” (28 September 2007, p. 1846), H. Xin reported that the first phase of the eastern route of the massive project has been delayed at least 3 years because of the low quality of the water to be diverted northward. The article then quoted Qian Ye from the U.S. National Center for Atmospheric Research in Boulder, Colorado [the same source as quoted by the earlier News Focus article “Going against the flow” (R. Stone and H. Jia, 25 August 2006, p. 1034)], who suggested that global warming “could make China’s north wetter and allow authorities to scale back the controversial project.” However, the perception of a wetter northern China is contrary to the common wisdom about the impact of global warming in this region. Meteorological records show that northern China has experienced a coupled warming and drying trend over the past several decades (1, 2). Both the Intergovernmental Panel on Climate Change (3) and the National Climate Change Program of China (4) foresee a drier condition in the coming decades for this part of China.

There is no shortage of reasons to reconsider the Chinese water canal project. But in the context of global warming, the quantity—and quality—of the water that the Yangtze could offer in the future is worthy of careful consideration. The river is fed by the glaciers and permafrost on the Tibetan plateau. The glacier area in northwestern China shrunk by 21% and the permafrost in the Plateau thinned dramatically in the past 50 years due to global warming (4). If its source continues to shrink, the Yangtze River might run out of water as well.

Shaopeng Huang

Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48109–1005, USA and Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China.

References

1. X. Zou, P. Zhai, Q. Zhang, Geophys. Res. Lett. 32, L04707, 10.1029/2004GL021853 (2005).

2. Z. Ma, X. Ren, Ad. Clim. Change Res. 3, 195 (2007).

3. R. T. Watson et al., “IPCC Special Report on The Regional Impacts of Climate Change An Assessment of Vulnerability,” (IPCC, 1997); www.grida.no/climate/ipcc/regional/261.htm.

4. China's National Climate Change Program, http://english.gov.cn/2007- 06/04/content_636052.htm.

n-week:
MARINE GEOLOGY: Support Is Drying Up for Noah's Flood Filling the Black Sea
Kerr (17 August 2007) [Full text] [PDF]
MARINE GEOLOGY: Support Is Drying Up for Noah's Flood Filling the Black Sea
Update on Black Sea Research
20 March 2008
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Gilles Lericolais,
Marine Geologist
Ifremer, Plouzané, France

Respond to this E-Letter:
Re: Update on Black Sea Research

In your article "Support is drying up for Noah's flood filling the Black Sea" (News of the Week by R. A. Kerr, 17 August 2007, p. 886) you refer to Richard Hiscott and Ali Aksu of Memorial University of Newfoundland and colleagues who have reported a delta south of the Bosporus built by outflowing waters 10,000 years ago (1). This article has been found wanting in analyses published by Turkish scientists, who like other international countries are often forgotten by United States or English-native writers. An interpretation based on high-resolution seismic stratigraphy has been published by E. Gökaşan et al. on delta formation at the southern entrance of the Istanbul Strait (2). It shows that the delta described by Aksu, Hiscott, and co-authors is the product of a Turkish river flowing to the Marmara Sea. The northern Black Sea shallow fan delta has already been presented by D. Di Ioro et al. (3) and confirmed by G. Lericolais et al. (4). Even though Hiscot et al. do not agree that there was a late connection of the Black Sea to the Mediterranean Sea, they have found evidence in cores recovered on the Black Sea Turkish shelf of a late salinization of the Black Sea that was obtained from their studies conducted (the one you are quoting). They explain that the Ostracoda of Caspian affinity indicates ~5‰ salinity until ~7.5 ka. Dinocysts and foraminifera confirm a low but rising salinity at no later than ~8.6 ka, and in 2007 a first major pulse of marine waters was recorded at around 8.46 ka BP by Marret et al. They propose a complicated explanation to refute a late reconnection as evidenced by relics, coastal dunes, and wave-cut terraces (Lericolais et al. 2007a, 2007b). This is consistent with the results obtained in 1975 by Maheim and Chan suggesting that during the isolation of the Black Sea in the LGM (Neoeuxinian) there was a relatively homogeneous chlorine concentration of about 3.5 g/kg, compared with more than 12 g/kg in the present-day bottom water.

I hope that this will help to refine the overview of ongoing studies carried out in the Black Sea. It is difficult to explain how the discovered features were set without a Black Sea level having been reduced to -100 m during the period between 11000 and 8000 years C14 BP.

Gilles Lericolais

European Coodinator of the ASSEMBLAGE European project on the assessment of the Quaternary sedimentary system of the Black Sea, Ifremer, Plouzané, France.

References

1. R. N. Hiscott et al, Quaternary International 167, 19 (June 2007).

2. E. Gökaşan et al., Geo-Marine Letters 25, 370 (2005).

3. D. Di Ioro, H. Yüce, Journal of Geophysical Research 104, 3091 (1999).

4. G. Lericolais et al., EOS transactions (2002).

r-articles:
The Product Space Conditions the Development of Nations
Hidalgo et al. (27 July 2007) [Abstract] [Full text] [PDF]
The Product Space Conditions the Development of Nations
Access to Product Space and Transformations Study Data
30 April 2008
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Cesar A. Hidalgo,
Research Fellow
Harvard Kennedy School

Respond to this E-Letter:
Re: Access to Product Space and Transformations Study Data

Thanks to J. Liu—all of these are good an interesting questions. We have made all of the data used for this study available at http://www.nd.edu/~networks/productspace. Please feel free to pursue or investigate any of them. As you might guess, there are many questions we have ourselves and the idea behind the paper can not be worked out in a single article.

Thanks for your comments.

Cesar A. Hidalgo

Research Fellow, Harvard Kennedy School

compviewpoint:
SCIENCE'S RESPONSE:
Is a Government Archive the Best Option?

Editors (23 March 2001) [Full text]
SCIENCE'S RESPONSE:
Is a Government Archive the Best Option?

The Copyright Laws Are Important
9 May 2008
Previous E-Letter  Top
James W. Farr,
Scientist
Self-employed

Respond to this E-Letter:
Re: The Copyright Laws Are Important

The copyright laws governing the use or distribution of scientific research that is catalogued or owned publicly in the U.S. are much less stringent than those governing privately run bodies holding research. I’m sure that other countries have different laws. The copyright laws should at least be scrutinized carefully before changing any rules governing the storing of scientific research in libraries.

James W. Farr


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