Causal information and social learning in chimpanzees (Pan troglodytes) and children (Homo sapiens)

Many of the tool-using activities of both chimpanzees and children involve a complex mixture of interconnected causal relationships between a tool and a reward, and much of this tool-use is thought to be acquired, at least in part, by social learning. However, despite the considerable research effort focused on both causal understanding and social learning, few studies have directly addressed the potential interaction between these areas. It seems likely that the way in which an individual learns to use a tool through observation will be significantly influenced by its understanding of the causal relationships that it observes. This thesis presents a series of nine experiments with 3- to 7-year-old chimpanzees and 3- 6-year-old children, designed to investigate whether causal information is involved in determining which social learning strategy they employ. The first set of experiments demonstrated that chimpanzees could be influence to switch between imitation and emulation to solve the same task, by altering the availability of causal information. When causal information was available, by presenting a tool-use task in a transparent condition, chimpanzees were found to reproduce only the results of a model's behaviour, consistent with emulation. However, when the availability of causal information was restricted, by presenting the same task in an opaque condition, the chimpanzees included a greater proportion of the model's behaviour, consistent with imitation. The second set of experiments revealed that chimpanzees could learn specific causal information by observation, such as the significance of tool-reward contact. However, they may be overwhelmed by observing multiple causal relationships, or those involving unobservable causal principles, such as gravity or force. The common view that the widespread evidence for emulation in chimpanzee social learning studies indicates a deficit of imitative capacity may therefore be misleading. The results of this thesis suggest more generally that when causal information is available, chimpanzees tend to use emulation. They are also able to imitate, but do so mainly in situations where emulation is not possible. Thus, the availability of causal information plays an important role in chimpanzee social learning, by determining which learning strategy is employed, and ultimately the degree of behavioural fidelity that is achieved, hi contrast, the studies with children revealed that they imitate the actions that they observe without appearing to consider the causal efficiency of their behaviour. This may be due to a greater focus on the actions of a demonstrator rather than the results or goals of their behaviour, and a greater tendency to interpret those actions as intentional

Modification of aftertaste with a menthol mouthwash reduces food wanting, liking, and ad <i>libitum </i>intake of potato crisps

This research investigated the effect of modifying the aftertaste of potato crisps on (1) temporal sensory perception and (2) appetite using three mouthwash conditions (no mouthwash, a water mouthwash, and a menthol mouthwash). For the sensory study, 17 screened female subjects were trained on the Temporal Dominance of Sensations (TDS) methodology. Subjects undertook TDS to monitor all sensory attributes during the mastication of a 2 g crisp until swallowing (at 20s), then conducted the mouthwash, and then continued the TDS task to monitor aftertaste until 90s. For the appetite study, 36 subjects (18 male, 18 female) completed 100 mm Visual Analogue Scales (VAS) for desire, liking, hunger, and thirst, followed by an ad libitum eating task. For the VAS scales testing, subjects chewed and swallowed a 2 g crisp, and then immediately conducted the mouthwash before completing the VAS scales. For the ad libitum task, subjects were given 12 min to consume as many crisps as they desired on a plate (up to 50 g). Every three minutes they were required to conduct a mouthwash. TDS results showed that in comparison with no mouthwash, the water mouthwash significantly reduced aftertaste attributes such as savoury, salty, and fatty mouthcoating, and the menthol mouthwash significantly increased aftertaste attributes of cooling, minty, and tingly. The water mouthwash did not influence desire and liking of crisps, or hunger and thirst. The water mouthwash did not influence ad libitum intake of the crisps over a 12 min period. The menthol mouthwash significantly reduced desire and liking of the crisps, as well as hunger and thirst. Furthermore, the menthol mouthwash significantly reduced ad libitum crisp intake by 29% over the 12 min period

Transmission of Multiple Traditions within and between Chimpanzee Groups

SummaryField reports provide increasing evidence for local behavioral traditions among fish, birds, and mammals [1–7]. These findings are significant for evolutionary biology because social learning affords faster adaptation than genetic change and has generated new (cultural) forms of evolution [8–10]. Orangutan and chimpanzee field studies [3, 4, 11–13] suggest that like humans [14, 15], these apes are distinctive among animals in each exhibiting over 30 local traditions. However, direct evidence is lacking in apes and, with the exception of vocal dialects [16, 17], in animals generally for the intergroup transmission that would allow innovations to spread widely and become evolutionarily significant phenomena. Here, we provide robust experimental evidence that alternative foraging techniques seeded in different groups of chimpanzees spread differentially not only within groups but serially across two further groups with substantial fidelity. Combining these results with those from recent social-diffusion studies in two larger groups [18–20] offers the first experimental evidence that a nonhuman species can sustain unique local cultures, each constituted by multiple traditions. The convergence of these results with those from the wild implies a richness in chimpanzees' capacity for culture, a richness that parsimony suggests was shared with our common ancestor

Insulated skin temperature as a measure of core body temperature for individuals wearing CBRN protective clothing

This study assessed the validity of insulated skin temperature (Tis) to predict rectal temperature (Tre) for use as a non-invasive measurement of thermal strain to reduce the risk of heat illness for emergency service personnel. Volunteers from the Police, Fire and Rescue, and Ambulance Services performed rolerelated tasks in hot (30 ◦C) and neutral (18 ◦C) conditions, wearing service specific personal protective equipment. Insulated skin temperature and micro climate temperature (Tmc) predicted Tre with an adjusted r2 = 0.87 and standard error of the estimate (SEE) of 0.19 ◦C. A bootstrap validation of the equation resulted in an adjusted r2 = 0.85 and SEE = 0.20 ◦C. Taking into account the 0.20 ◦C error, the prediction of Tre resulted in a sensitivity and specificity of 100% and 91%, respectively. Insulated skin temperature and Tmc can be used in a model to predict Tre in emergency service personnel wearing CBRN protective clothing with an SEE of 0.2 ◦C. However, the model is only valid for Tis over 36.5 ◦C, above which thermal stability is reached between the core and the skin

Prestige Affects Cultural Learning in Chimpanzees

Humans follow the example of prestigious, high-status individuals much more readily than that of others, such as when we copy the behavior of village elders, community leaders, or celebrities. This tendency has been declared uniquely human, yet remains untested in other species. Experimental studies of animal learning have typically focused on the learning mechanism rather than on social issues, such as who learns from whom. The latter, however, is essential to understanding how habits spread. Here we report that when given opportunities to watch alternative solutions to a foraging problem performed by two different models of their own species, chimpanzees preferentially copy the method shown by the older, higher-ranking individual with a prior track-record of success. Since both solutions were equally difficult, shown an equal number of times by each model and resulted in equal rewards, we interpret this outcome as evidence that the preferred model in each of the two groups tested enjoyed a significant degree of prestige in terms of whose example other chimpanzees chose to follow. Such prestige-based cultural transmission is a phenomenon shared with our own species. If similar biases operate in wild animal populations, the adoption of culturally transmitted innovations may be significantly shaped by the characteristics of performers

Variable Glycemic Responses to Intact and Hydrolyzed Milk Proteins in Overweight and Obese Adults Reveal the Need for Precision Nutrition

peer-reviewedBackground Dietary modifications can contribute to improved pancreatic β cell function and enhance glycemic control. Objectives The objectives of this study were as follows: 1) to investigate the potential of milk protein hydrolysates to modulate postprandial glucose response; 2) to assess individual responses; and 3) to explore the inter- and intraindividual reproducibility of the response. Methods A 14-d randomized crossover study investigated interstitial glucose levels of participants in response to 12% w/v milk protein drinks (intact caseinate and casein hydrolysate A and B) consumed in random order with a 2-d washout between treatments. Milk protein drinks were consumed immediately prior to study breakfast and evening meals. Twenty participants (11 men, 9 women) aged 50 ± 8 y with a body mass index (in kg/m2) of 30.2 ± 3.1 were recruited. Primary outcome was glucose levels assessed at 15-min intervals with the use of glucose monitors. Results Repeated-measures ANOVA revealed that for breakfast there was a significant difference across the 3 treatment groups (P = 0.037). The ability to reduce postprandial glucose was specific to casein hydrolysate B in comparison with intact caseinate (P = 0.039). However, despite this significant difference, further examination revealed that only 3 out of 18 individuals were classified as responders (P < 0.05). High intraclass correlation coefficients were obtained for glucose response to study meals (intraclass correlation coefficient: 0.892 for breakfast with intact caseinate). The interindividual CVs were higher than the intraindividual CVs. Mean inter- and intraindividual CVs were 19.4% and 5.7%, respectively, for breakfast with intact caseinate. Conclusion Ingestion of a specific casein hydrolysate successfully reduced the postprandial glucose response; however, at an individual level only 3 participants were classified as responders, highlighting the need for precision nutrition. Exploration of high interindividual responses to nutrition interventions is needed, in combination with the development of precision nutrition, potentially through an n-of-1 approach. This clinical trial was registered as ISRCTN61079365 (https://www.isrctn.com/).Food for Health Irelan

The fundamental connections between the Solar System and exoplanetary science

Over the past several decades, thousands of planets have been discovered outside our Solar System. These planets exhibit enormous diversity, and their large numbers provide a statistical opportunity to place our Solar System within the broader context of planetary structure, atmospheres, architectures, formation, and evolution. Meanwhile, the field of exoplanetary science is rapidly forging onward toward a goal of atmospheric characterization, inferring surface conditions and interiors, and assessing the potential for habitability. However, the interpretation of exoplanet data requires the development and validation of exoplanet models that depend on in situ data that, in the foreseeable future, are only obtainable from our Solar System. Thus, planetary and exoplanetary science would both greatly benefit from a symbiotic relationship with a two way flow of information. Here, we describe the critical lessons and outstanding questions from planetary science, the study of which are essential for addressing fundamental aspects for a variety of exoplanetary topics. We outline these lessons and questions for the major categories of Solar System bodies, including the terrestrial planets, the giant planets, moons, and minor bodies. We provide a discussion of how many of these planetary science issues may be translated into exoplanet observables that will yield critical insight into current and future exoplanet discoveries

Evolution of long-term vaccine-induced and hybrid immunity in healthcare workers after different COVID-19 vaccine regimens

BACKGROUND: Both infection and vaccination, alone or in combination, generate antibody and T cell responses against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the maintenance of such responses-and hence protection from disease-requires careful characterization. In a large prospective study of UK healthcare workers (HCWs) (Protective Immunity from T Cells in Healthcare Workers [PITCH], within the larger SARS-CoV-2 Immunity and Reinfection Evaluation [SIREN] study), we previously observed that prior infection strongly affected subsequent cellular and humoral immunity induced after long and short dosing intervals of BNT162b2 (Pfizer/BioNTech) vaccination. METHODS: Here, we report longer follow-up of 684 HCWs in this cohort over 6-9 months following two doses of BNT162b2 or AZD1222 (Oxford/AstraZeneca) vaccination and up to 6 months following a subsequent mRNA booster vaccination. FINDINGS: We make three observations: first, the dynamics of humoral and cellular responses differ; binding and neutralizing antibodies declined, whereas T and memory B cell responses were maintained after the second vaccine dose. Second, vaccine boosting restored immunoglobulin (Ig) G levels; broadened neutralizing activity against variants of concern, including Omicron BA.1, BA.2, and BA.5; and boosted T cell responses above the 6-month level after dose 2. Third, prior infection maintained its impact driving larger and broader T cell responses compared with never-infected people, a feature maintained until 6 months after the third dose. CONCLUSIONS: Broadly cross-reactive T cell responses are well maintained over time-especially in those with combined vaccine and infection-induced immunity ("hybrid" immunity)-and may contribute to continued protection against severe disease

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure