Of Dogs and Bonds

In four of Charles Darwin’s classic works (Darwin, 1859, 1868, 1871, 1872), the domestic dog (Canis familiaris or Canis lupus familiaris)1 featured prominently, offering key examples to illustrate his ideas about evolution, domestication, comparative behavior and cognition, and emotional expression. Darwin held a clear fondness for dogs, and when replying to letters detailing the “sagacity” of dogs, he remarked “I can believe almost anything about them” (Darwin, 2014). Despite the early interest in their behavior and cognition by a number of leading scientists, dogs were rarely subject to serious investigation as a study species for 150 years. In 2000, the number of studies on dog behavior and cognition began increasing rapidly, as more behavioral researchers worldwide began to work with them (Aria et al., 2021; Bensky et al., 2013). This research covers both the social and nonsocial domains of behavior and cognition (Bensky et al., 2013; Miklósi, 2015). In the social domain, researchers study how dogs interact with social agents (both conspecifics and heterospecifics) in areas such as play, social relationships, perspective taking, cooperation, communication, and social learning. In the nonsocial domain, researchers study how dogs interact with their physical environment by investigating perception, learning, memory, categorization, physical reasoning, numerical cognition, and spatial cognition. Combined, this work has highlighted dogs as an ideal study system for understanding the evolution of behavior and cognition, domestication and co-evolution, applied animal science, and even human health (ManyDogs Project et al., 2023). Many species exhibit fascinating aspects of behavior and cognition. But what sets dogs apart is their relationship with humans. No other species has been invited into our homes, farms, schools, hospitals, libraries, and airports to the degree that dogs have. They have an exaggerated presence in the media we consume, from beloved cartoon characters such as Peanut’s Snoopy to a pudgy little pug setting the morning mood for millions of people on social media (Graziano, 2022). Further, many people identify as “pet parents” and treat their dogs as they would their children (Volsche, 2021). Mirroring the dog cognition trends, we have recently witnessed a sharp increase in studies of canine-human interaction, exploring the motivational, emotional, cognitive, physiological, and neural mechanisms of dogs on human psychology and well-being. Despite increase in both dog cognition and canine-human interaction, there is not as much cross talk between these fields as one might hope for. Here, we bring these research fields together to take seriously the questions of why dogs play such an important role in our hearts and minds and why the canine-human bond is so strong

Geotechnical testing and Finite Element Modeling of Geomorphic Landform Design with a Multi-Layer Cap and Cover System

This research was aimed at implementation of Geomorphic Landform Design (GLD) principles to the Royal Scot abandoned coal refuse disposal facility in Greenbrier County, West Virginia, USA. This facility currently exhibits many undesirable environmental problems including acid-mine drainage and significant erosion and sediment transport.;A multi-layer cap and cover system in conjunction with GLD principles was proposed as a solution to these environmental problems. This cover is proposed to be constructed from the coarse coal refuse material on-site and a short paper fiber material (MGro(TM)) from the MeadWestVaco paper mill in nearby Covington, Virginia, USA. To determine the possible effectiveness of this design, multiple research stages were completed. First, the principles of GLD and landform covers were investigated, as well as the use and properties of coarse coal refuse combined with short paper fiber. Second, a suite of geotechnical laboratory testing was completed on the materials to be used in the construction. Third, the cap and cover system was designed based on the measured geotechnical parameters. Fourth, the cap and cover system was applied to three reclamation alternatives and its seepage control performance and geotechnical stability were analyzed by the finite element method (FEM) for slope stability and seepage using SVFlux(TM) and SVSlopeRTM computer modeling software.;Geotechnical testing results concurred with literature and tended to indicate that blending short paper fiber at 40 percent with 60 percent coarse coal refuse (volumetric ratio); along with layers of 100% coarse coal refuse at Royal Scot could make an effective cap and cover system. Short paper fiber is a suitable growth media in literature and laboratory testing of a MGro(TM) and coarse coal refuse blended (60/40) material indicated a suitably strong material with an internal angle of friction of approximately 30°. The coarse coal refuse shale material (100%) had a friction angle of 40° with hydraulic conductivity values of 10-6 to 10-7 cm/s when compacted to standard proctor effort. Constructing a cover with a 0.915m (3 ft) thick 60/40 MGro / coarse coal refuse growth layer, a 0.915m (3 ft) thick drainage layer of loose coal refuse, and a 0.915 m (3 ft) thick layer of compacted coal refuse. The total cap thickness was 2.75 m (9 ft) which produced a cover system capable of reducing seepage into the underlying acid-generating fill by 85%. The cap and cover system was stable on slopes up to 21.8°.;FEM stability modeling indicated that the cover design could be applied to a design of the Royal Scot re-graded to geomorphic profiles. The design was stable, with a geotechnical factor of safety over the required minimum 1.5 on slopes less than or equal to 21.8°. Additionally, seepage into the acid-generating fill was shown to be reduced by nearly 75%. With the addition of internal drains, which will be required on shallower slope benches of the reclamation to reduce the accumulation of internal pore water pressure, the seepage reduction was further reduced by 10%, which is a nearly 85% reduction of infiltration

Replicability and Reproducibility in Comparative Psychology

Psychology faces a replication crisis. The Reproducibility Project: Psychology sought to replicate the effects of 100 psychology studies. Though 97% of the original studies produced statistically significant results, only 36% of the replication studies did so (Open Science Collaboration, 2015). This inability to replicate previously published results, however, is not limited to psychology (Ioannidis, 2005). Replication projects in medicine (Prinz et al., 2011) and behavioral economics (Camerer et al., 2016) resulted in replication rates of 25 and 61%, respectively, and analyses in genetics (Munafò, 2009) and neuroscience (Button et al., 2013) question the validity of studies in those fields. Science, in general, is reckoning with challenges in one of its basic tenets: replication. Comparative psychology also faces the grand challenge of producing replicable research. Though social psychology has born the brunt of most of the critique regarding failed replications, comparative psychology suffers from some of the same problems faced by social psychology (e.g., small sample sizes). Yet, comparative psychology follows the methods of cognitive psychology by often using within-subjects designs, which may buffer it from replicability problems (Open Science Collaboration, 2015). In this Grand Challenge article, I explore the shared and unique challenges of and potential solutions for replication and reproducibility in comparative psychology

Intertemporal similarity: Discounting as a last resort

Standard models of intertemporal choice assume that individuals discount future payoffs by integrating reward amounts and time delays to generate a discounted value. Alternative models propose that, rather than integrate across them, individuals compare within attributes (amounts and delays) to determine if differences in one attribute outweigh differences in another attribute. For instance, Leland (2002) and Rubinstein (2003) propose models that 1) compare the two reward amounts to determine whether they are similar, 2) compare the similarity of the two time delays, and then 3) make a decision based on these similarity judgments. Here, I tested discounting models against attribute-based models that use similarity judgments to make choices. I collected intertemporal choices and similarity judgments for the reward amounts and time delays from participants in three experiments. All experiments tested the ability of discounting and similarity models to predict intertemporal choices. Model generalization analyses showed that the best predicting models started with similarity judgments and then, if similarity failed to make a prediction, resorted to discounting models. Similarity judgments also matched intertemporal choice data demonstrating both the magnitude and sign effects, thereby accounting for behavioral data that contradict many discounting models. These results highlight the possibility that attribute-based models such as the similarity models provide alternatives to discounting that may offer insights into the process of making intertemporal choices

The Selfish Nature of Generosity: Harassment and Food Sharing in Primates

Animals may share food to gain immediate or delayed fitness benefits. Previous studies of sharing have concentrated on delayed benefits such as reciprocity, trade and punishment. This study tests an alternative model (the harassment or sharing–under–pressure hypothesis) in which a food owner immediately benefits because sharing avoids costly harassment from a beggar. I present an experiment that varies the potential ability of the beggar to harass, and of the owner to defend the food, to examine the effects of harassment on food sharing in two primate species: chimpanzees (Pan troglodytes) and squirrel monkeys (Saimiri boliviensis). For both species, high levels of harassment potential significantly increased both beggar harassment and sharing by the owner. Food defensibility did not affect harassment or sharing. Interestingly, squirrel monkeys and chimpanzees shared equally frequently with conspecifics despite a much higher natural sharing rate in chimpanzees. These results suggest that harassment can play a significant role in primate food sharing, providing a simple alternative to reciprocity. The selfish nature of harassment has implications for economic, psychological and evolutionary studies of cooperative systems

Evolutionary pressures on primate intertemporal choice

From finding food to choosing mates, animals must make intertemporal choices that involve fitness benefits available at different times. Species vary dramatically in their willingness to wait for delayed rewards. Why does this variation across species exist? An adaptive approach to intertemporal choice suggests that time preferences should reflect the temporal problems faced in a species\u27 environment. Here, I use phylogenetic regression to test whether allometric factors (relating to body size), relative brain size, and social group size predict how long 13 primate species will wait in laboratory intertemporal choice tasks. Controlling for phylogeny, a composite allometric factor that includes body mass, absolute brain size, lifespan, and home range size predicted waiting times, but relative brain size and social group size did not. These findings support the notion that selective pressures have sculpted intertemporal choices to solve adaptive problems faced by animals. Collecting these types of data across a large number of species can provide key insights into the evolution of decision making and cognition. Supplementary files are attached below

Mechanisms for Decisions about the Future

Evolutionary and psychological perspectives on decision making remain largely separate endeavors. The bounded rationality approach integrates these two perspectives by focusing on simple, plausible mechanisms of decision making and the cognitive capacities needed to implement these mechanisms. Decisions about the future provide a class of decisions that lend themselves to a bounded rationality approach. Though many different mechanisms may exist for making decisions about the future, only a subset of these mechanisms actually require a representation of the future. The bounded rationality approach helps focus on the cognitive capacities and decision mechanisms that are necessary for a full understanding of decision making about the future. Volume bibliography attached (below) as an additional file

Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

Informed by the research on adaptive decision making in other animal species, this study investigated human females’ intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males), become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women’s fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making

A Precise Dispenser Design for Canine Cognition Research

Some forms of canine cognition research require a dispenser that can accurately dispense precise quantities of treats. When using off-the-shelf or retrofitted dispensers, there is no guarantee that a precise number of treats will be dispensed. Often, they will over-dispense treats, which may not be acceptable for some tasks. Here we describe a 3D-printed precise treat dispenser with a 59-treat capacity driven by a stepper motor drive and controlled by an integrated Raspberry Pi. The dispenser can be built for less than 200 USD and is fully 3D printable. While off-the-shelf dispensers can result in an error rate of 20–30%, the precision dispenser produces a 4% error rate. This lower error rate and the integrated Raspberry Pi allows for new possibilities for using treat dispensers across a range of canine research questions

Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

Informed by the research on adaptive decision making in other animal species, this study investigated human females’ intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males), become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women’s fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making