Getting to Evo-Devo: Concepts and Challenges for Students Learning Evolutionary Developmental Biology

To examine how well biology majors have achieved the necessary foundation in evolution, numerous studies have examined how students learn natural selection. However, no studies to date have examined how students learn developmental aspects of evolution (evo-devo). Although evo-devo plays an increasing role in undergraduate biology curricula, we find that instruction often addresses development cursorily, with most of the treatment embedded within instruction on evolution. Based on results of surveys and interviews with students, we suggest that teaching core concepts (CCs) within a framework that integrates supporting concepts (SCs) from both evolutionary and developmental biology can improve evo-devo instruction. We articulate CCs, SCs, and foundational concepts (FCs) that provide an integrative framework to help students master evo-devo concepts and to help educators address specific conceptual difficulties their students have with evo-devo. We then identify the difficulties that undergraduates have with these concepts. Most of these difficulties are of two types: those that are ubiquitous among students in all areas of biology and those that stem from an inadequate understanding of FCs from developmental, cell, and molecular biology.     

Facial patterning and infant emotional expression: happiness, surprise, and fear

Although recent studies have convincingly demonstrated that emotional expressions can be judged reliably from actor-posed facial displays, there exists little evidence that facial expressions in lifelike settings are similar to actor-posed displays, are reliable across situations designed to elicit the same emotion, or provide sufficient information to mediate consistent emotion judgments by raters. The present study therefore investigated these issues as they related to the emotions of happiness, surprise, and fear. 27 infants between 10 and 12 months of age (when emotion masking is not likely to confound results) were tested in 2 situations designed to elicit hapiness (peek-a-boo game and a collapsing toy), 2 to elicit surprise (a toy-switch and a vanishing-object task), and 2 to elicit fear (the visual cliff and the approach of a stranger. Dependent variables included changes in 28 facial response components taken from previous work using actor poses, as well as judgments of the presence of 6 discrete emotions. In addition, instrumental behaviors were used to verify with other than facial expression responses whether the predicted emotion was elicited. In contrast to previous conclusions on the subject, we found that judges were able to make all facial expression judgments reliably, even in the absence of contextual information. Support was also obtained for at least some degree of specificity of facial component response patterns, especially for happiness and surprise. Emotion judgments by raters were found to be a function of the presence of discrete facial components predicted to be linked to those emotions. Finally, almost all situations elicited blends, rather than discrete emotions.     

Early risk, attention, and brain activation in adolescents born preterm

The relations among early cumulative medical risk, cumulative environmental risk, attentional control, and brain activation were assessed in 15-16-year-old adolescents who were born preterm. Functional magnetic resonance imaging found frontal, temporal, and parietal cortex activation during an attention task with greater activation of the left superior-temporal and left supramarginal gyri associated with better performance. Individual differences in early cumulative risk are related to patterns of brain activation such that medical risk is related to left parietal cortex activation and environmental risk is related to temporal lobe activation. The findings suggest that early risk is related to less mature patterns of brain activation, including reduced efficiency of processing and responding to stimuli.     

The EvoDevoCI: A Concept Inventory for Gauging Students’ Understanding of Evolutionary Developmental Biology

The American Association for the Advancement of Science 2011 report Vision and Change in Undergraduate Biology Education encourages the teaching of developmental biology as an important part of teaching evolution. Recently, however, we found that biology majors often lack the developmental knowledge needed to understand evolutionary developmental biology, or “evo-devo.” To assist in efforts to improve evo-devo instruction among undergraduate biology majors, we designed a concept inventory (CI) for evolutionary developmental biology, the EvoDevoCI. The CI measures student understanding of six core evo-devo concepts using four scenarios and 11 multiple-choice items, all inspired by authentic scientific examples. Distracters were designed to represent the common conceptual difficulties students have with each evo-devo concept. The tool was validated by experts and administered at four institutions to 1191 students during preliminary (n = 652) and final (n = 539) field trials. We used student responses to evaluate the readability, difficulty, discriminability, validity, and reliability of the EvoDevoCI, which included items ranging in difficulty from 0.22–0.55 and in discriminability from 0.19–0.38. Such measures suggest the EvoDevoCI is an effective tool for assessing student understanding of evo-devo concepts and the prevalence of associated common conceptual difficulties among both novice and advanced undergraduate biology majors.     

Effects of Isometric Work on Heart Rate,Blood Pressure,and Net Oxygen Cost

Abstract

A study was made on the effects of a 10-sec. isometric exercise, which involved much of the large musculature, upon the heart-rate, blood pressure, and net oxygen cost. Six subjects exercised in a semireclining, fixed position against a Medart spring dynamometer. Each subject pulled to 60 percent of his previously determined maximum effort. Heart rate showed a slight increase during exercise followed by a sharp rise in the few seconds following exercise. This was followed by a drop almost to the resting level within 20 to 30 sec. following exercise. Systolic pressure rose following exercise and was highest in the period immediately following exercise, then dropped slowly to resting levels within 2 1/2 min. Oxygen consumption varied widely both between subjects and between experiments in the same subject.     

Volunteer services for vulnerable families and at-risk elderly

OBJECTIVE: The purpose of this paper is to explore the role of the volunteer with vulnerable populations, specifically, new parents and their infants and at-risk elderly. As demand for volunteer services increases due to budgetary and personnel reductions, a better understanding of volunteers as service providers is imperative. METHOD: A review of the literature related to volunteers who work with these two populations was conducted. Volunteer characteristics, roles, needs of populations served, recruitment, and training issues were addressed, specifically as they relate to the two populations. RESULTS: Studies indicate that the socio-demographic range of volunteers is wide, as are the motivations for volunteering. Similarities between the needs of new families and the elderly exist, and volunteers for both populations often provide supportive and pragmatic services. Volunteers for both populations are further challenged to maintain a client-focused intervention, a task which may be more difficult in the home. Training of volunteers was found to be both client and volunteer driven, with the needs of the population being served and the role of the volunteer within a specific service domain of prime importance. CONCLUSION: Similarities between infant and elder populations exist, as do volunteer interventions with these populations. A theoretical framework for defining motivation, designing need-based training, and addressing the role of volunteers is discussed. The use of volunteers as compassionate and cost-effective service providers for populations across the lifespan not only provides an increase in the number of skilled workers involved with these vulnerable populations, but also allows professional staff to expand the care which they are able to provide.     

Characteristics of volunteers and families in a neonatal home visitation project: the Kempe Community Caring Program

OBJECTIVE: The purpose of this paper is to review literature related to home visitation support for new families using volunteer visitors and to describe characteristics of volunteers of the Kempe Community Caring Program, a home visitor support program for first time parents. Suggestions for effectively utilizing volunteers in family support programs are made. METHOD: Program data was collected and reviewed on 592 volunteer home visitors and the 1,144 families they served. Several evaluations and assessments were performed in order to attempt to measure the success of the intervention. Motivation for volunteering, longevity with program, and the extent of sociodemographic match between visitor and client were reviewed and discussed. RESULTS: Information on matched volunteer-client pairs was limited; however, speculations were made that neither motivation to participate nor sociodemographic match were critical factors in determining success of the intervention. Duration of volunteer participation was influenced by marital status, but not by age. Married volunteers stayed with the program significantly longer than unmarried volunteers. Low risk families demonstrated slightly improved confidence in parental function after receiving home visitation by a volunteer. CONCLUSION: This program suggests that new mothers may benefit from receiving the services of a volunteer home visitor; specifically, their confidence as parents and ability to establish positive relationships show slight improvement. Likewise, volunteers and families felt satisfied with the supportive relationships generated. In addition, a volunteer profile emerged which may be beneficial to similar programs' recruiting efforts.