On the Hypothetico-Deductive Nature of Science—Darwin’s Finches

Allchin (2006) has misinterpreted a classic case of hypothetico-deductive (HD) science in terms of his preferred ‘let’s-gather-some-data-and-see-what-emerges’ view. The misrepresentation concerns the research program of Peter and Rosemary Grant on Darwin’s finches. The present essay argues that the Grants’ research is HD in nature and includes a statement by Peter Grant to that effect.

---

Mathematical Manipulative Models: In Defense of “Beanbag Biology”

Mathematical manipulative models have had a long history of influence in biological research and in secondary school education, but they are frequently neglected in undergraduate biology education. By linking mathematical manipulative models in a four-step process—1) use of physical manipulatives, 2) interactive exploration of computer simulations, 3) derivation of mathematical relationships from core principles, and 4) analysis of real data sets—we demonstrate a process that we have shared in biological faculty development workshops led by staff from the BioQUEST Curriculum Consortium over the past 24 yr. We built this approach based upon a broad survey of literature in mathematical educational research that has convincingly demonstrated the utility of multiple models that involve physical, kinesthetic learning to actual data and interactive simulations. Two projects that use this approach are introduced: The Biological Excel Simulations and Tools in Exploratory, Experiential Mathematics (ESTEEM) Project (http://bioquest.org/esteem) and Numerical Undergraduate Mathematical Biology Education (NUMB3R5 COUNT; http://bioquest.org/numberscount). Examples here emphasize genetics, ecology, population biology, photosynthesis, cancer, and epidemiology. Mathematical manipulative models help learners break through prior fears to develop an appreciation for how mathematical reasoning informs problem solving, inference, and precise communication in biology and enhance the diversity of quantitative biology education.     

A jaundiced bodybuilder Cholestatic hepatitis as side effect of injectable anabolic–androgenic steroids

The use of anabolic steroids is prevalent in recreational athletes. This case report describes a young amateur bodybuilder who was referred to our outpatient clinic with jaundice and loss of appetite due to cholestatic hepatitis. Additional tests including a liver biopsy made it likely that the hepatitis was caused by the injectable anabolic steroid trenbolone enanthate. Cholestatic hepatitis may not be limited to the use of oral anabolic–androgenic steroids, as is widely assumed. Therefore, and because of other side effects, the recreational use of all forms of anabolic steroids should be discouraged.     

Scale-free collaborative protocol design for state and regulated state synchronization of multi-agent systems with arbitrary fast convergence

In this paper, we design scale-free collaborative protocols for state and regulated state synchronization of homogeneous multi-agent systems (MAS) with arbitrary fast convergence. The protocol design solely depends on the knowledge of the agents’ model and does not require any information about the communication network and the number of agents. Moreover, our protocols can achieve synchronization with any desired convergence rate by simply tuning a design parameter.     

Environmental Education Network within the EEC

Pascual‐Leone (1972) has conducted task analyses in terms of M‐demand (amount of information processing required by the task) and demonstrated that the phenomenon of ‘horizontal decalages’, described by Piaget, can be accounted for by increasing demands of information processing. It has been shown that formal operational reasoning is required to balance even simple, one‐step chemical equations, while formal reasoning and a sufficiently large M‐capacity are required to balance more complex, multi‐step chemical equations. The objective of the present study is to investigate the relation between functional M‐capacity (M_f) and student performance in solving chemistry problems of increasing M‐demand. It was found that student performance decreased as the M‐demand of the problems increased. Similarly, the correlation coefficients between M_f‐ and student performance increased progressively as the M‐demand of the problems increased.     

Linking Brain Growth with the Development of Scientific Reasoning Ability and Conceptual Change during Adolescence

The hypothesis that an early adolescent brain growth plateau and spurt exists and that this plateau and spurt influence students' ability to reason scientifically and to learn theoretical science concepts was tested. In theory, maturation of the prefrontal lobes during early adolescence allows for improvements in students' abilities to inhibit task‐irrelevant information and coordinate task‐relevant information, which along with both physical and social experience influences scientific reasoning ability and the ability to reject scientific misconceptions and accept scientific conceptions. Two hundred ten students ages 13–16 years enrolled in four Korean secondary schools were administered tests of four prefrontal lobe activities, a test of scientific reasoning ability, and a test of air pressure concepts derived from kinetic‐molecular theory. A series of 14 lessons designed to teach the concepts were then taught. The concepts test was then readministered following instruction. As predicted, among the 13‐ and 14‐year‐olds, performance on the prefrontal lobe measures remained similar or regressed. Performance then improved considerably among the 15‐ and 16‐year‐olds. Also as expected, the measures of prefrontal lobe activity correlated highly with scientific reasoning ability. In turn, prefrontal lobe activity and scientific reasoning ability predicted concept gains and posttest performance. A principal components analysis showed that the study variables had two main components, which were interpreted as an inhibiting and a representing component. Therefore, theoretical concept acquisition was interpreted as a process involving both the inhibition of task‐irrelevant information (i.e., the rejection of intuitively derived misconceptions) and the representation of task‐relevant information (i.e, complex hypothetico‐deductive arguments and counterintuitive scientific conceptions about nonobservable entities). © 2000 John Wiley & Sons, Inc. J Res Sci Teach 37: 44–62, 2000