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Acoustic phenotypic variation is of major importance for speciation and the evolution of species diversity. Whereas selective and stochastic forces shaping the acoustic divergence of signaling systems are well studied in insects, frogs, and birds, knowledge on the processes driving acoustic phenotypic evolution in mammals is limited. We quantified the acoustic variation of a call type exchanged during agonistic encounters across eight distinct species of the smallest‐bodied nocturnal primate radiation, the Malagasy mouse lemurs. The species live in two different habitats (dry forest vs. humid forest), differ in geographic distance to each other, and belong to four distinct phylogenetic clades within the genus. Genetically defined species were discriminated reliably on the phenotypic level based on their acoustic distinctiveness in a discriminant function analysis. Acoustic variation was explained by genetic distance, whereas differences in morphology, forest type, or geographic distance had no effect. The strong impact of genetics was supported by a correlation between acoustic and genetic distance and the high agreement in branching pattern between the acoustic and molecular phylogenetic trees. In sum, stochastic factors such as genetic drift best explained acoustic diversification in a social communication call of mouse lemurs. [ABSTRACT FROM AUTHOR]

The article discusses the unique dietary observations of the Eastern lesser bamboo lemur, Hapalemur griseus, in the Analamazaotra Forest in Eastern Madagascar. The lemurs were observed consuming various plant species, including bamboo, mushrooms, and fruits. The study highlights the importance of fungi in the lemurs' diet and the potential role of Auricularia species in their food sources. The article also mentions the high level of biodiversity and endemism in Madagascar, particularly in relation to lemurs. [Extracted from the article]

Mouse lemurs (Microcebus spp.) are one of the most diverse lineages of lemurs. They are difficult to study under field conditions, and there is a lack of basic behavioural data for many species. Recently, semi-captive conditions, i.e., when individuals are housed in temporary enclosures in proximity to their capture sites, have emerged as an alternative method to study a range of topics in challenging species. In this study, we use this setting to compare the activity budgets in three species of mouse lemur, namely M. ravelobensis, M. bongolavensis, and M. myoxinus, in northwest Madagascar. The objective of this work was to understand how semi-captivity might influence behaviour. We housed 24 wild mouse lemurs (with 12 male and 12 female adults) under semi-captive conditions for six consecutive nights in mixed-sex dyads with a similar body mass and collected scan sampling and behavioural states every 15 seconds from 18:00 to 21:00 We found no evidence of stereotypic behaviour, including pacing or over self-grooming. On average, mouse lemurs spent 83% of their time resting inside shelter boxes, 14% of their time moving, and 2% of their time self-grooming. None of these daily behaviours changed in frequency across the one-week study period. We found moderate differences between species, with M. myoxinus resting more and self-grooming less than either M. ravelobensis or M. bongolavensis. While recognizing the limitations of our study and of semi-captivity more generally, we highlight the potential comparative information to be gained from semi-captive experiments across species, conditions, and fields of study. [ABSTRACT FROM AUTHOR]

Objectives: The investigation of morphological variation in animals is widely used in taxonomy, ecology, and evolution. Using large datasets for meta‐analyses has dramatically increased, raising concerns about dataset compatibilities and biases introduced by contributions of multiple researchers. Materials and Methods: We compiled morphological data on 13 variables for 3073 individual mouse lemurs (Cheirogaleidae, Microcebus spp.) from 25 taxa and 153 different sampling locations, measured by 48 different researchers. We introduced and applied a filtering pipeline and quantified improvements in data quality (Shapiro‐Francia statistic, skewness, and excess kurtosis). The filtered dataset was then used to test for genus‐wide sexual size dimorphism and the applicability of Rensch's, Allen's, and Bergmann's rules. Results: Our pipeline reduced inter‐observer bias (i.e., increased normality of data distributions). Inter‐observer reliability of measurements was notably variable, highlighting the need to reduce data collection biases. Although subtle, we found a consistent pattern of sexual size dimorphism across Microcebus, with females being the larger (but not heavier) sex. Sexual size dimorphism was isometric, providing no support for Rensch's rule. Variations in tail length but not in ear size were consistent with the predictions of Allen's rule. Body mass and length followed a pattern contrary to predictions of Bergmann's rule. Discussion: We highlighted the usefulness of large multi‐researcher datasets for testing ecological hypotheses after correcting for inter‐observer biases. Using genus‐wide tests, we outlined generalizable patterns of morphological variability across all mouse lemurs. This new methodological toolkit aims to facilitate future large‐scale morphological comparisons for a wide range of taxa and applications. [ABSTRACT FROM AUTHOR]

Frequent kin-biased coalitionary behaviour is a hallmark of mammalian social complexity. Furthermore, selection to understand complex social dynamics is believed to underlie the co-evolution of social complexity and large brains. Vocalisations have been shown to be an important mechanism with which large-brained mammals living in complex social groups recognise and recruit kin for coalitionary support during agonistic conflicts. We test whether kin recognition via agonistic calls occurs in a small-brained solitary foraging primate living in a dispersed social network, the grey mouse lemur (Microcebus murinus, Miller JF, 1777). As mouse lemurs are frequent models for ancestral solitary foraging mammals, this study examines whether kin recognition via agonistic calls could be the foundation from which more complex, kin-based coalitionary behaviour evolved. We test whether female wild mouse lemurs in Ankarafantsika National Park, Madagascar, react differently to agonistic calls from kin and nonkin and to calls from familiar and unfamiliar individuals during playback experiments. Subjects showed no significant differences in reactions to the different stimuli; thus they did not react differently based upon kinship or familiarity. Results suggest that this solitary foraging species does not use agonistic calls to recognise kin and monitor agonistic interactions involving kin, unlike several species of Old World monkeys and hyenas. Thus, kin recognition via agonistic calls may have evolved independently in these lineages in parallel with greater social complexity and frequent coalitionary behaviour. [ABSTRACT FROM AUTHOR]

Reproduction is a fundamental trait in the life history of any species and contributes to species diversity and evolution. Here, we aim to review the barely known variation in reproductive patterns of the smallest‐bodied primate radiation, the Malagasy mouse lemurs, focusing on twelve species of four phylogenetic clades. We present a new reproductive field dataset collected between May and November 1996–2016 for nine species (Microcebus murinus, M. myoxinus, M. ravelobensis, M. bongolavensis, M. danfossi, M. sambiranensis, M. margothmarshae, M. mamiratra, and M. lehilahytsara) and add published field information on three additional species. In the majority of species, the estrus of females was recorded in the period of long days (day length longer than 12 hr), whereas male testes size increased about one to three months prior to this. Reproductive schedules varied considerably between the four clades. Sympatric species‐pairs of different clades differed in the timing of female and male reproduction, suggesting strong phylogenetic constraints. Populations of the same species in a different ecological setting varied in the onset of reproduction, suggesting substantial environmental plasticity. Warm temperatures and rainfall throughout the year may allow for less expressed reproductive seasonality. Our results suggest that an interplay between phylogenetic relatedness, ambient temperature (as a proxy for thermo regulatory constraints), and rainfall (as a proxy for food availability), may best explain this variation. Findings further point to a more complex control of mouse lemur reproduction than previously described and illuminate phylogenetic constraints and adaptive potentials in behavioral reaction norms of a species‐rich primate radiation. [ABSTRACT FROM AUTHOR]

Introduction Maternal kin selection is a driving force in the evolution of mammalian social complexity and it requires that kin are distinctive from nonkin. The transition from the ancestral state of asociality to the derived state of complex social groups is thought to have occurred via solitary foraging, in which individuals forage alone, but, unlike the asocial ancestors, maintain dispersed social networks via scent-marks and vocalizations. We hypothesize that matrilineal signatures in vocalizations were an important part of these networks. We used the solitary foraging gray mouse lemur (Microcebus murinus) as a model for ancestral solitary foragers and tested for matrilineal signatures in their calls, thus investigating whether such signatures are already present in solitary foragers and could have facilitated the kin selection thought to have driven the evolution of increased social complexity in mammals. Because agonism can be very costly, selection for matrilineal signatures in agonistic calls should help reduce agonism between unfamiliar matrilineal kin. We conducted this study on a well-studied population of wild mouse lemurs at Ankarafantsika National Park, Madagascar. We determined pairwise relatedness using seven microsatellite loci, matrilineal relatedness by sequencing the mitrochondrial D-loop, and sleeping group associations using radio-telemetry. We recorded agonistic calls during controlled social encounters and conducted a multi-parametric acoustic analysis to determine the spectral and temporal structure of the agonistic calls. We measured 10 calls for each of 16 females from six different matrilineal kin groups. Results Calls were assigned to their matriline at a rate significantly higher than chance (pDFA: correct = 47.1%, chance = 26.7%, p = 0.03). There was a statistical trend for a negative correlation between acoustic distance and relatedness (Mantel Test: g = -1.61, Z = 4.61, r = - 0.13, p = 0.058). Conclusions Mouse lemur agonistic calls are moderately distinctive by matriline. Because sleeping groups consisted of close maternal kin, both genetics and social learning may have generated these acoustic signatures. As mouse lemurs are models for solitary foragers, we recommend further studies testing whether the lemurs use these calls to recognize kin. This would enable further modeling of how kin recognition in ancestral species could have shaped the evolution of complex sociality. [ABSTRACT FROM AUTHOR]

Background: The 2009 World Health Organisation (WHO) surgical safety checklist significantly reduces surgical mortality and morbidity (up to 47%). Yet in 2016, only 25% of East African anesthetists regularly use the checklist. Nationwide implementation of the checklist is reported in high-income countries, but in low- and middle-income countries (LMICs) reports of successful implementations are sparse, limited to single institutions and require intensive support. Since checklist use leads to the biggest improvements in outcomes in LMICs, methods of wide-scale implementation are needed. We hypothesized that, using a three-day course, successful wide-scale implementation of the checklist could be achieved, as measured by at least 50% compliance with six basic safety processes at three to four months. We also aimed to determine predictors for checklist utilization. Materials and methods: Using a blended educational implementation strategy based on prior pilot studies we designed a three-day dynamic educational course to facilitate widespread implementation of the WHO checklist. The course utilized lectures, film, small group breakouts, participant feedback and simulation to teach the knowledge, skills and behavior changes needed to implement the checklist. In collaboration with the Ministry of Health and local hospital leadership, the course was delivered to 427 multi-disciplinary staff at 21 hospitals located in 19 of 22 regions of Madagascar between September 2015 and March 2016. We evaluated implementation at three to four months using questionnaires (with a 5-point Likert scale) and focus groups. Multivariate linear regression was used to test predictors of checklist utilization. Results: At three to four months, 65% of respondents reported always using the checklist, with another 13% using it in part. Participant’s years in practice, hospital size, or surgical volume did not predict checklist use. Checklist use was associated with counting instruments (p< 0.05), but not with verifying: patient identity, difficult intubation risk, risk of blood loss, prophylactic antibiotic administration, or counting needles and sponges. Conclusion: Use of a multi-disciplinary three-day course for checklist implementation resulted in 78% of participants using the checklist, at three months; and an increase in counting surgical instruments. Successful checklist implementation was not predicted by participant length of medical service, hospital size or surgical volume. If reproducible in other countries, widespread implementation in LMICs becomes a realistic possibility. [ABSTRACT FROM AUTHOR]

Background: The Lancet Commission on Global Surgery (LCoGS) described the lack of access to safe, affordable, timely surgical, and anesthesia care. It proposed a series of 6 indicators to measure surgery, accompanied by time-bound targets and a template for national surgical planning. To date, no sub-Saharan African country has completed and published a nationwide evaluation of its surgical system within this framework. Method: Mercy Ships, in partnership with Harvard Medical School and the Madagascar Ministry of Health, collected data on the 6 indicators from 22 referral hospitals in 16 out of 22 regions of Madagascar. Data collection was by semi-structured interviews with ministerial, medical, laboratory, pharmacy, and administrative representatives in each region. Microsimulation modeling was used to calculate values for financial indicators. Results: In Madagascar, 29% of the population can access a surgical facility within 2 h. Surgical workforce density is 0.78 providers per 100,000 and annual surgical volume is 135-191 procedures per 100,000 with a perioperative mortality rate of 2.5-3.3%. Patients requiring surgery have a 77.4-86.3 and 78.8-95.1% risk of incurring impoverishing and catastrophic expenditure, respectively. Of the six LCoGS indicator targets, Madagascar meets one, the reporting of perioperative mortality rate. Conclusion: Compared to the LCoGS targets, Madagascar has deficits in surgical access, workforce, volume, and the ability to offer financial risk protection to surgical patients. Its perioperative mortality rate, however, appears better than in comparable countries. The government is committed to improvement, and key stakeholder meetings to create a national surgical plan have begun. [ABSTRACT FROM AUTHOR]