Developmental plasticity of the stress response in female but not in male guppies

To survive, animals must respond appropriately to stress. Stress responses are costly, so early-life experiences with potential stressors could adaptively tailor adult stress responses to local conditions. However, how multiple stressors influence the development of the stress response remains unclear, as is the role of sex. Trinidadian guppies (Poecilia reticulata) are small fish with extensive life-history differences between the sexes and population variation in predation pressure and social density. We investigated how sex and early-life experience influence hormonal stress responses by manipulating conspecific density and perceived predation risk during development. In adults, we sampled cortisol twice to measure initial release and change over time in response to a recurring stressor. The sexes differed considerably in their physiological stress response. Males released more cortisol for their body mass than females and did not reduce cortisol release over time. By contrast, all females, except those reared at high density together with predation cues, reduced cortisol release over time. Cortisol responses of males were thus less dynamic in response to current circumstances and early-life experiences than females, consistent with life-history differences between the sexes. Our study underscores the importance of early-life experiences, interacting ecological factors and sex differences in the organization of the stress response

Edge detection in static and dynamic environments using robot swarms

<b>Table S2</b>: Estimates and standard error of fixed parameters and their interactions for the GLMM with response variable cortisol concentration per gram of body mass per hour (ng/g/h) during phase 1. Estimates are given on the scale of the “inverse” link (1/x), and negative estimate values thus represent an increase in cortisol concentration. The model estimates represent the difference between the level of a factor (identified in parenthesis) with the reference levels. As our factors each contain two levels, the estimates represent the difference between the two groups. The reference levels were no-predator cues for predation, high density, and females. Housing group was included as random effect in the model. Significant p values (p < 0.05) are shown in bold

Data from: Developmental plasticity of the stress response in female but not male guppies

To survive, animals must respond appropriately to stress. Stress responses are costly, so early-life experiences with potential stressors could adaptively tailor adult stress responses to local conditions. However, how multiple stressors influence the development of the stress response remains unclear, as is the role of sex. Trinidadian guppies (Poecilia reticulata) are small fish with extensive life history differences between the sexes and population variation in predation pressure and social density. We investigated how sex and early-life experience influence hormonal stress responses by manipulating conspecific density and perceived predation risk during development. In adults, we sampled cortisol twice to measure initial release and change over time in response to a recurring stressor. The sexes differed considerably in their physiological stress response. Males released more cortisol for their body mass than females and did not reduce cortisol release over time. By contrast, all females, except those reared at high density with predation cues, reduced cortisol release over time. Cortisol responses of males were less dynamic in response to current circumstances and early-life experiences than females, consistent with life history differences between the sexes. Our study underscores the importance of early-life experiences, interacting ecological factors, and sex differences in the organization of the stress response

The Tomlinson Engagement Award for Mentoring (TEAM) at McGill University promotes student engagement

Large undergraduate class sizes limit the interactions students can have with the course instructors and teaching assistant(s). This can translate to lower student engagement and consequently lower academic performance. To mitigate this effect, the Tomlinson Teaching Project (established in 2002) launched a program in 2013, The Tomlinson Engagement Award for Mentoring (TEAM), that aims to improve the quality and accessibility of education to undergraduate students. Through the TEAM program, undergraduate students who were successful in a course are selected to assist the instructor with course delivery the following year. TEAM members are awarded $ 300 (not taxed) for 25-30 hours of service. They may undertake tasks such as participating in tutorial sessions and responding to online discussion posts. Additionally, TEAM members have taken initiatives to offer extra help and exam review sessions for students. To date, there have been over 1000 TEAM members participating in over 146 courses mainly from McGill University’s STEM departments. As a tool to measure program success, feedback forms are completed by course instructors and TEAM members at the end of each term. From the 2016 academic year, 98 % of TEAM members (n= 56) perceived that their support had a positive impact on the students learning experience. Similarly, according to course instructor feedback (n= 32), 97 % perceived TEAM members to be valuable to them and their students. We hope that these findings will provide support for the growth of the TEAM program at McGill University, consequently improving student learning experiences

Dataset from Developmental plasticity of the stress response in female but not in male guppies

Data of cortisol collection experiment on fish reared in a 2x2 design manipulating early life experience of predation and density

Dynamic interactions among people, livestock, and savanna: ecosystems under climate change

A poster prepared for the ILRI Annual Program Meeting (APM) 2010, held at ILRI campus, Addis Ababa, Ethiopia, April 14-17, 201

Supplementary information from Developmental plasticity of the stress response in female but not in male guppies

Details of fish feeding and housing, as well as cortisol extraction. Tables of supplementary data analysis

Dataset from Developmental plasticity of the stress response in female but not in male guppies

Data of cortisol collection experiment on fish reared in a 2x2 design manipulating early life experience of predation and density

Technical and conceptual considerations for using animated stimuli in studies of animal behavior

Rapid technical advances in the field of computer animation (CA) and virtual reality (VR) have opened new avenues in animal behavior research. Animated stimuli are powerful tools as they offer standardization, repeatability, and complete control over the stimulus presented, thereby "reducing" and "replacing" the animals used, and "refining" the experimental design in line with the 3Rs. However, appropriate use of these technologies raises conceptual and technical questions. In this review, we offer guidelines for common technical and conceptual considerations related to the use of animated stimuli in animal behavior research. Following the steps required to create an animated stimulus, we discuss (I) the creation, (II) the presentation, and (III) the validation of CAs and VRs. Although our review is geared toward computer-graphically designed stimuli, considerations on presentation and validation also apply to video playbacks. CA and VR allow both new behavioral questions to be addressed and existing questions to be addressed in new ways, thus we expect a rich future for these methods in both ultimate and proximate studies of animal behavior

Experimental evidence for the co-evolution of hominin tool-making teaching and language

Hominin reliance on Oldowan stone tools—which appear from 2.5 mya and are believed to have been socially transmitted—has been hypothesized to have led to the evolution of teaching and language. Here we present an experiment investigating the efficacy of transmission of Oldowan tool-making skills along chains of adult human participants (N=184) using five different transmission mechanisms. Across six measures, transmission improves with teaching, and particularly with language, but not with imitation or emulation. Our results support the hypothesis that hominin reliance on stone tool-making generated selection for teaching and language, and imply that (i) low-fidelity social transmission, such as imitation/emulation, may have contributed to the ~700,000 year stasis of the Oldowan technocomplex, and (ii) teaching or proto-language may have been pre-requisites for the appearance of Acheulean technology. This work supports a gradual evolution of language, with simple symbolic communication preceding behavioural modernity by hundreds of thousands of years