Can captive orangutans (Pongo pygmaeus abelii) be coaxed into cumulative build-up of techniques?

While striking cultural variation in behavior from one site to another has been described in chimpanzees and orangutans, cumulative culture might be unique to humans. Captive chimpanzees were recently found to be rather conservative, sticking to the technique they had mastered, even after more effective alternatives were demonstrated. Behavioral flexibility in problem solving, in the sense of acquiring new solutions after having learned another one earlier, is a vital prerequisite for cumulative build-up of techniques. Here, we experimentally investigate whether captive orangutans show such flexibility, and if so, whether they show techniques that cumulatively build up (ratchet) on previous ones after conditions of the task are changed. We provided nine Sumatran orangutans (Pongo pygmaeus abelii) with two types of transparent tubes partly filled with syrup, along with potential tools such as sticks, twigs, wood wool and paper. In the first phase, the orangutans could reach inside the tubes with their hands (Regular Condition), but in the following phase, tubes had been made too narrow for their hands to fit in (Restricted Condition 1), or in addition the setup lacked their favorite materials (Restricted Condition 2). The orangutans showed high behavioral flexibility, applying nine different techniques under the regular condition in total. Individuals abandoned preferred techniques and switched to different techniques under restricted conditions when this was advantageous. We show for two of these techniques how they cumulatively built up on earlier ones. This suggests that the near-absence of cumulative culture in wild orangutans is not due to a lack of flexibility when existing solutions to tasks are made impossible

Cardiac evaluation of candidates for kidney transplantation: value of exercise radionuclide angiocardiography

In view of the high incidence and mortality of coronary artery disease (CAD) in patients with kidney transplantation, a systematic cardiac evaluation was prospectively performed in 103 uraemic patients eligible for transplantation. After clinical examination, 28 patients with symptoms of CAD or diabetes mellitus were referred directly for coronary angiography, whereas the remaining 75 patients had rest and exercise radionuclide angiocardiography for evaluation of possible asymptomatic CAD. Among them, left ventricular ejection fraction was below 40% at rest or fell during exercise by at least 5 EF% in 12 patients; coronary angiography in nine showed CAD in four and hypertensive heart disease in five. In the remaining 63 (of 75) patients without severe resting left ventricular dysfunction or exercise ischaemia, the follow-up of 28 ±7 months revealed no clinical manifestation of CAD. Overall incidence of CAD in symptomatic and asymptomatic patients during a follow-up of 27 months after cardiac evaluation was 20 and 25% in non-diabetic and diabetic candidates for kidney transplantation, respectively (P = n.s.). Thus, clinical examination combined with exercise radionuclide angiocardiography in patients without signs or symptoms of heart disease had a high predictive accuracy for presence or absence of late manifestations of CAD. Exercise radionuclide angiocardiography is therefore a useful method for screening kidney transplantation candidates for asymptomatic CA

A First Look at Rotation in Inactive Late-Type M Dwarfs

We have examined the relationship between rotation and activity in 14 late-type (M6-M7) M dwarfs, using high resolution spectra taken at the W.M. Keck Observatory and flux-calibrated spectra from the Sloan Digital Sky Survey. Most were selected to be inactive at a spectral type where strong H-alpha emission is quite common. We used the cross-correlation technique to quantify the rotational broadening; six of the stars in our sample have vsini > 3.5 km/s. Our most significant and perplexing result is that three of these stars do not exhibit H-alpha emission, despite rotating at velocities where previous work has observed strong levels of magnetic field and stellar activity. Our results suggest that rotation and activity in late-type M dwarfs may not always be linked, and open several additional possibilities including a rotationally-dependent activity threshold, or a possible dependence on stellar parameters of the Rossby number at which magnetic/activity "saturation" takes place in fully convective stars.Comment: 8 pages, 4 figures, accepted for publication in Ap

The evolutionary drivers of primate scleral coloration

The drivers of divergent scleral morphologies in primates are currently unclear, though white sclerae are often assumed to underlie human hyper-cooperative behaviours. Humans are unusual in possessing depigmented sclerae whereas many other extant primates, including the closely-related chimpanzee, possess dark scleral pigment. Here, we use phylogenetic generalized least squares (PGLS) analyses with previously generated species-level scores of proactive prosociality, social tolerance (both n = 15 primate species), and conspecific lethal aggression (n = 108 primate species) to provide the first quantitative, comparative test of three existing hypotheses. The ‘self-domestication’ and ‘cooperative eye’ explanations predict white sclerae to be associated with cooperative, rather than competitive, environments. The ‘gaze camouflage’ hypothesis predicts that dark scleral pigment functions as gaze direction camouflage in competitive social environments. Notably, the experimental evidence that non-human primates draw social information from conspecific eye movements is unclear, with the latter two hypotheses having recently been challenged. Here, we show that white sclerae in primates are associated with increased cooperative behaviours whereas dark sclerae are associated with reduced cooperative behaviours and increased conspecific lethal violence. These results are consistent with all three hypotheses of scleral evolution, suggesting that primate scleral morphologies evolve in relation to variation in social environment

Cross-Sectional Associations of 24-Hour Sedentary Time, Physical Activity, and Sleep Duration Compositions with Sleep Quality and Habits in Preschoolers

Although some studies indicate physical activity and sleep quality are positively associated in children, most reports examined physical activity independent of other 24-h behaviors and focused on older children. The aim of this cross-sectional study was to examine the predicted changes in sleep efficiency and habits when reallocating time between movement behaviors using compositional isotemporal substitution in preschool-aged children. Accelerometers were worn by 288 participants (51.6 ± 9.5 months) for up to 16 days. Sleep outcomes included sleep efficiency, nap frequency, sleep disturbances, and bedtime resistance. Compositional isotemporal substitution analyses demonstrated that the combined effect of 24-h movement behaviors was associated with sleep efficiency (p \u3c 0.001) and nap frequency (p \u3c 0.003). When sleep increased by 30 min at the expense of stationary time or light physical activity, estimates of sleep efficiency and bedtime resistance decreased while nap frequency increased. When stationary time increased by 30 min from moderate to vigorous physical activity, estimated sleep efficiency increased and sleep disturbances decreased. Although this study presents preliminary evidence that 24-h movement behavior compositions in early childhood are associated with sleep quality and nap frequency, estimated effects from theoretical time reallocations across sleep outcomes were mixed

Towards a Notion of Distributed Time for Petri Nets

We set the ground for research on a timed extension of Petri nets where time parameters are associated with tokens and arcs carry constraints that qualify the age of tokens required for enabling. The novelty is that, rather than a single global clock, we use a set of unrelated clocks --- possibly one per place --- allowing a local timing as well as distributed time synchronisation. We give a formal definition of the model and investigate properties of local versus global timing, including decidability issues and notions of processes of the respective models

A convergent interaction engine: vocal communication among marmoset monkeys

To understand the primate origins of the human interaction engine, it is worthwhile to focus not only on great apes but also on callitrichid monkeys (marmosets and tamarins). Like humans, but unlike great apes, callitrichids are cooperative breeders, and thus habitually engage in coordinated joint actions, for instance when an infant is handed over from one group member to another. We first explore the hypothesis that these habitual cooperative interactions, the marmoset interactional ethology, are supported by the same key elements as found in the human interaction engine: mutual gaze (during joint action), turn-taking, volubility, as well as group-wide prosociality and trust. Marmosets show clear evidence of these features. We next examine the prediction that, if such an interaction engine can indeed give rise to more flexible communication, callitrichids may also possess elaborate communicative skills. A review of marmoset vocal communication confirms unusual abilities in these small primates: high volubility and large vocal repertoires, vocal learning and babbling in immatures, and voluntary usage and control. We end by discussing how the adoption of cooperative breeding during human evolution may have catalysed language evolution by adding these convergent consequences to the great ape-like cognitive system of our hominin ancestors. This article is part of the theme issue ‘Revisiting the human ‘interaction engine’: comparative approaches to social action coordination’

Putting the cart before the horse? The origin of information donation

Heintz & Scott-Phillips propose that the partner choice ecology of our ancestors required Gricean cognitive pragmatics for reputation management, which caused a tendency toward showing and expecting prosociality that subsequently scaffolded language evolution. Here, we suggest a cognitively leaner explanation that is more consistent with comparative data and posits that prosociality and eventually language evolved along with cooperative breeding

The impact of a randomized controlled trial of a lifestyle intervention on postpartum physical activity among at-risk hispanic women: Estudio PARTO

AIMS: To assess the impact of a culturally modified, motivationally targeted, individually-tailored intervention on postpartum physical activity (PA) and PA self-efficacy among Hispanic women. METHODS: Estudio PARTO was a randomized controlled trial conducted in Western Massachusetts from 2013-17. Hispanic women who screened positive for gestational diabetes mellitus were randomized to a Lifestyle Intervention (LI, n = 100) or to a comparison Health and Wellness (HW, n = 104) group during late pregnancy. Exercise goals in LI were to meet American College of Obstetrician and Gynecologists guidelines for postpartum PA. The Pregnancy Physical Activity Questionnaire (PPAQ) and the Self-Efficacy for Physical Activity Questionnaire were administered at 6 weeks, 6 months, and 1 year postpartum. RESULTS: Compared to baseline levels, both groups had significant increases in moderate-to-vigorous PA at 6 months and one year postpartum (i.e., LI: mean change = 30.9 MET-hrs/wk, p = 0.05; HW: 27.6 MET-hrs/wk, p = 0.01), with only LI group experiencing significant increases in vigorous PA (mean change = 1.3 MET-hrs/wk, p = 0.03). Based on an intent-to-treat analysis using mixed effects models, we observed no differences in pattern of change in PA intensity and type over time between intervention groups (all p \u3e 0.10). However, there was the suggestion of a greater decrease in sedentary activity in the LI group compared to the HW group (beta = -3.56, p = 0.09). CONCLUSIONS: In this randomized trial among high-risk Hispanic women, both groups benefitted from participation in a postpartum intervention