The Nature of Expertise in Fingerprint Matching: Experts Can Do a Lot with a Little

Expert decision making often seems impressive, even miraculous. People with genuine expertise in a particular domain can perform quickly and accurately, and with little information. In the series of experiments presented here, we manipulate the amount of “information” available to a group of experts whose job it is to identify the source of crime scene fingerprints. In Experiment 1, we reduced the amount of information available to experts by inverting fingerprint pairs and adding visual noise. There was no evidence for an inversion effect—experts were just as accurate for inverted prints as they were for upright prints—but expert performance with artificially noisy prints was impressive. In Experiment 2, we separated matching and nonmatching print pairs in time. Experts were conservative, but they were still able to discriminate pairs of fingerprints that were separated by five-seconds, even though the task was quite different from their everyday experience. In Experiment 3, we separated the print pairs further in time to test the long-term memory of experts compared to novices. Long-term recognition memory for experts and novices was the same, with both performing around chance. In Experiment 4, we presented pairs of fingerprints quickly to experts and novices in a matching task. Experts were more accurate than novices, particularly for similar nonmatching pairs, and experts were generally more accurate when they had more time. It is clear that experts can match prints accurately when there is reduced visual information, reduced opportunity for direct comparison, and reduced time to engage in deliberate reasoning. These findings suggest that non-analytic processing accounts for a substantial portion of the variance in expert fingerprint matching accuracy. Our conclusion is at odds with general wisdom in fingerprint identification practice and formal training, and at odds with the claims and explanations that are offered in court during expert testimony.     

What Does Africa Have to Do with Being African American? A Microethnographic Analysis of a Middle School Inquiry Unit on Africa

In the United States, "race" and "black identity" are becoming more complex with the increasing numbers of individuals who identify as "black and foreignborn." Emanating from a year-long study in an urban middle school classroom and a microethnographic investigation of a two-week unit on Africa, this article employs a Pan-African framework to examine how schools and the broader society serve as sites where black identity is contested. The article concludes with implications for education, society, and the study of race and black identity in classroom life.     

What Do I Want and When Do I Want It: Brain Correlates of Decisions Made for Self and Other

A number of recent functional Magnetic Resonance Imaging (fMRI) studies on intertemporal choice behavior have demonstrated that so-called emotion- and reward-related brain areas are preferentially activated by decisions involving immediately available (but smaller) rewards as compared to (larger) delayed rewards. This pattern of activation was not seen, however, when intertemporal choices were made for another (unknown) individual, which speaks to that activation having been triggered by self-relatedness. In the present fMRI study, we investigated the brain correlates of individuals who passively observed intertemporal choices being made either for themselves or for an unknown person. We found higher activation within the ventral striatum, medial prefrontal and orbitofrontal cortex, pregenual anterior cingulate cortex, and posterior cingulate cortex when an immediate reward was possible for the observer herself, which is in line with findings from studies in which individuals actively chose immediately available rewards. Additionally, activation in the dorsal anterior cingulate cortex, posterior cingulate cortex, and precuneus was higher for choices that included immediate options than for choices that offered only delayed options, irrespective of who was to be the beneficiary. These results indicate that (1) the activations found in active intertemporal decision making are also present when the same decisions are merely observed, thus supporting the assumption that a robust brain network is engaged in immediate gratification; and (2) with immediate rewards, certain brain areas are activated irrespective of whether the observer or another person is the beneficiary of a decision, suggesting that immediacy plays a more general role for neural activation. An explorative analysis of participants’ brain activation corresponding to chosen rewards, further indicates that activation in the aforementioned brain areas depends on the mere presence, availability, or actual reception of immediate rewards.     

Germination of Spores of Bacillus Species: What We Know and Do Not Know

Spores of Bacillus species can remain in their dormant and resistant states for years, but exposure to agents such as specific nutrients can cause spores'' return to life within minutes in the process of germination. This process requires a number of spore-specific proteins, most of which are in or associated with the inner spore membrane (IM). These proteins include the (i) germinant receptors (GRs) that respond to nutrient germinants, (ii) GerD protein, which is essential for GR-dependent germination, (iii) SpoVA proteins that form a channel in spores'' IM through which the spore core''s huge depot of dipicolinic acid is released during germination, and (iv) cortex-lytic enzymes (CLEs) that degrade the large peptidoglycan cortex layer, allowing the spore core to take up much water and swell, thus completing spore germination. While much has been learned about nutrient germination, major questions remain unanswered, including the following. (i) How do nutrient germinants penetrate through spores'' outer layers to access GRs in the IM? (ii) What happens during the highly variable and often long lag period between the exposure of spores to nutrient germinants and the commitment of spores to germinate? (iii) What do GRs and GerD do, and how do these proteins interact? (iv) What is the structure of the SpoVA channel in spores'' IM, and how is this channel gated? (v) What is the precise state of the spore IM, which has a number of novel properties even though its lipid composition is very similar to that of growing cells? (vi) How is CLE activity regulated such that these enzymes act only when germination has been initiated? (vii) And finally, how does the germination of spores of clostridia compare with that of spores of bacilli?     

Peasantry and City: Cultural Persistence and Change in Historical Perspective, a European Case

It is generally believed that peasant culture is incompatible with industrial civilization. Furthermore, peasant-city relationships are often dichotomized, suggesting maximal cultural distance. In view of data gathered in a peasant village of the Lower Rhineland it is argued here that over a period of seventy years at least the villagers were able not only to survive within an industrial civilization without losing their cultural identity but also to we industrial wage-earning as a means of preserving the essentials of their peasant way of life. Their ability to adapt to technological change is related here to a long history of previous adaptations beginning in the Middle Ages and leading to the Second Agricultural Revolution. Historical comparison between the city and the village suggests cultural continuity of urban lower class and peasantry rather than cultural polarity between the two segments. [Europe, culture and society; culture change; peasant culture]     

What minimal models cannot tell: a comment on "A model of phytoplankton blooms"

Huppert et al. analyzed a simple model describing bottom-up control of phytoplankton blooms. While we appreciate the mathematical aspects of this article, we feel that the fit of their model to data of Lake Kinneret is overly optimistic because the time axis was rescaled in an arbitrary way. Furthermore, one of the main conclusions of the article (bottom-up control is more likely to occur than top-down control) cannot, in our opinion, be drawn from a minimal model because such a model focuses on one explanation. It cannot be used to reveal the relative importance of alternative explanations.     

Dislocating Ethnographic Film: In and Out of Africa and Issues of Cultural Representation

In and Out of Africa. 1992. 59 minutes, color. Produced and directed by Ilisa Barbash and Lucien Taylor. Original research by Christopher Steiner. Featuring Gabai Baaré. University of California Extension, Center for Media and Independent Learning, 2000 Center St., 4th Floor, Berkeley, CA 94704. (510) 642-0460.     

"Stony the Road" to Change: Black Mississippians and the Culture of Social Relations

"Stony the Road" to Change: Black Mississippians and the Culture of Social Relations. Marilyn Thomas-Houston. New York: Cambridge University Press, 2005. 213 pp.     

What Shelters Can Do About Euthanasia-Related Stress: An Examination of Recommendations From Those on the Front Line

Shelter employees with euthanasia responsibilities are an at-risk population for a variety of psychological and emotional ailments. This study surveyed 305 employees from 62 shelters throughout the United States to gather first-hand perspectives on what should be done to assist shelter workers in dealing with euthanasia-related stress. Researchers conducted a qualitative analysis of 359 improvement suggestions to identify broad common themes and sorted the suggestions into 26 thematic categories. The most common participant suggestion concerned management supportive-ness (13.17% of participants). Some other issues raised involved providing counseling, job rotation, assistance or more help, breaks and time off, support groups and meetings, better communication, skills-based training, stress and coping seminars, and employee appreciation and morale-boosting initiatives.     

Altitudinal Change in the Photosynthetic Capacity of Tropical Trees: A Case Study from Ecuador and a Pantropical Literature Analysis

In tropical mountains, trees are the dominant life form from sea level to above 4,000-m altitude under highly variable thermal conditions (range of mean annual temperatures: <8 to >28°C). How light-saturated net photosynthesis of tropical trees adapts to variation in temperature, atmospheric CO₂ concentration, and further environmental factors, that change along elevation gradients, is not precisely known. With gas exchange measurements in mature trees, we determined light-saturated net photosynthesis at ambient temperature (T) and [CO₂] (A _sat) of 40 tree species from 21 families in tropical mountain forests at 1000-, 2000-, and 3000-m elevation in southern Ecuador. We tested the hypothesis that stand-level averages of A _sat and leaf dark respiration (R _D) per leaf area remain constant with elevation. Stand-level means of A _sat were 8.8, 11.3, and 7.2?μmol?CO₂?m^?2?s^?1; those of R _D 0.8, 0.6, and 0.7?μmol?CO₂?m^?2?s^?1 at 1000-, 2000-, and 3000-m elevation, respectively, with no significant altitudinal trend. We obtained coefficients of among-species variation in A _sat and R _D of 20–53% (n?=?10–16 tree species per stand). Examining our data in the context of a pan-tropical A _sat data base for mature tropical trees (c. 170 species from 18 sites at variable elevation) revealed that area-based A _sat decreases in tropical mountains by, on average, 1.3?μmol?CO₂?m^?2?s^?1?per?km altitude increase (or by 0.2?μmol?CO₂?m^?2?s^?1 per K temperature decrease). The A _sat decrease occurred despite an increase in leaf mass per area with altitude. Local geological and soil fertility conditions and related foliar N and P concentrations considerably influenced the altitudinal A _sat patterns. We conclude that elevation is an important influencing factor of the photosynthetic activity of tropical trees. Lowered A _sat together with a reduced stand leaf area decrease canopy C gain with elevation in tropical mountains.     

Cultural Transmission and the Diffusion of Innovations: Adoption Dynamics Indicate That Biased Cultural Transmission Is the Predominate Force in Behavioral Change

In challenging the pervasive model of individual actors as cost-benefit analysts who adapt their behavior by learning from the environment, this article analyzes the temporal dynamics of both environmental (individual) learning and biased cultural transmission processes by comparing these dynamics with the robust "5-shaped" curves that emerge from the diffusion of innovations literature. The analysis shows three things: (1) that environmental learning alone never produces the 5-shaped adoption dynamics typically observed in the spread of novel practices, ideas, and technologies; (2) that biased cultural transmission always produces the S-shaped temporal dynamics; and (3) that a combination of environmental learning and biased cultural transmission can generate 5-dynamics but only when biased cultural transmission is the predominate force in the spread of new behaviors. These findings suggest that biased cultural transmission processes are much more important to understanding the diffusion of innovations and sociocultural evolution than is often assumed by most theorists. [ diffusion of innovations, cultural transmission, learning, cultural evolution ]     

Cultural Pattern and Process: A Study of Stylistic Change in Women's Dress

Using time series analysis and systems theory it is possible to translate Kroeber's idea of a cultural configuration and its processual consequences into a less ambiguous model. By employing a mathematical formulation certain features of stylistic change in women's dress become evident: it is stochastic/probabilistic in nature and it is in stable equilibrium. The sequence of women's fashions through time would appear to arise from simultaneous operation of inertia, cultural continuity, a rule system of esthetic proportions, and an inherently unpredictable element.