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The dwarf lemurs (Cheirogaleus spp.) of Madagascar are the only obligate hibernators among primates. Despite century‐old field accounts of seasonal lethargy, and more recent evidence of hibernation in the western fat‐tailed dwarf lemur (Cheirogaleus medius), inducing hibernation in captivity remained elusive for decades. This included the Duke Lemur Center (DLC), which maintains fat‐tailed dwarf lemurs and has produced sporadic research on reproduction and metabolism. With cumulative knowledge from the field, a newly robust colony, and better infrastructure, we recently induced hibernation in DLC dwarf lemurs. We describe two follow‐up experiments in subsequent years. First, we show that dwarf lemurs under stable cold conditions (13°C) with available food continued to eat daily, expressed shallower and shorter torpor bouts, and had a modified gut microbiome compared to peers without food. Second, we demonstrate that dwarf lemurs under fluctuating temperatures (12–30°C) can passively rewarm daily, which was associated with altered patterns of fat depletion and reduced oxidative stress. Despite the limitations of working with endangered primates, we highlight the promise of studying hibernation in captive dwarf lemurs. Follow‐up studies on genomics and epigenetics, metabolism, and endocrinology could have relevance across multidisciplinary fields, from biomedicine to evolutionary biology, and conservation. [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]

Feast-fast cycles allow animals to live in seasonal environments by promoting fat storage when food is plentiful and lipolysis when food is scarce. Fat-storing hibernators have mastered this cycle over a circannual schedule, by undergoing extreme fattening to stockpile fuel for the ensuing hibernation season. Insulin is intrinsic to carbohydrate and lipid metabolism and is central to regulating feast-fast cycles in mammalian hibernators. Here, we examine glucose and insulin dynamics across the feast-fast cycle in fat-tailed dwarf lemurs, the only obligate hibernator among primates. Unlike cold-adapted hibernators, dwarf lemurs inhabit tropical forests in Madagascar and hibernate under various temperature conditions. Using the captive colony at the Duke Lemur Center, we determined fasting glucose and insulin, and glucose tolerance, in dwarf lemurs across seasons. During the lean season, we maintained dwarf lemurs under stable warm, stable cold, or fluctuating ambient temperatures that variably included food provisioning or deprivation. Overall, we find that dwarf lemurs can show signatures of reversible, lean-season insulin resistance. During the fattening season prior to hibernation, dwarf lemurs had low glucose, insulin, and HOMA-IR despite consuming high-sugar diets. In the active season after hibernation, glucose, insulin, HOMA-IR, and glucose tolerance all increased, highlighting the metabolic processes at play during periods of weight gain versus weight loss. During the lean season, glucose remained low, but insulin and HOMA-IR increased, particularly in animals kept under warm conditions with daily food. Moreover, these lemurs had the greatest glucose intolerance in our study and had average HOMA-IR values consistent with insulin resistance (5.49), while those without food under cold (1.95) or fluctuating (1.17) temperatures did not. Remarkably low insulin in dwarf lemurs under fluctuating temperatures raises new questions about lipid metabolism when animals can passively warm and cool rather than undergo sporadic arousals. Our results underscore that seasonal changes in insulin and glucose tolerance are likely hallmarks of hibernating mammals. Because dwarf lemurs can hibernate under a range of conditions in captivity, they are an emerging model for primate metabolic flexibility with implications for human health. [ABSTRACT FROM AUTHOR]

Captive wildlife benefit from ecologically informed management strategies that promote natural behaviors. The Duke Lemur Center has pioneered husbandry programs rooted in species' ecology for a diversity of lemurs, including housing social groups in multiacre forest enclosures. We systematically document the foraging and ranging patterns of Coquerel's sifakas (Propithecus coquereli) living in these forest enclosures. Coquerel's sifakas are seasonal frugo‐folivores that exhibit striking feeding flexibility in the wild. They are also one of the few members of the Indriidae family to persist in captivity. During all‐day follows in the spring and summer of 2 consecutive years, we tracked the behavior of 14 sifakas in six forest enclosures. The sifakas' ranging and foraging patterns reflected those of wild sifakas in western Madagascar: On average, DLC sifakas occupied 3‐day home ranges of 1.2 ha, traveled 473 m/day, and spent 26% of their time foraging for wild foodstuffs. The sifakas foraged most for young and mature leaves, fruits, nuts, and flowers from 39 plant species, especially red maple (Acer rubrum), tulip poplar (Liriodendron tulipifera), black locust (Robinia pseudoacacia), grapevine (Vitis rotundifolia), hickory (Carya spp.), and white oak (Quercus alba). Foraging patterns varied across seasons, enclosure areas, and groups, potentially reflecting differences in phenology, microhabitats, and individual preferences. While demonstrating that captive‐bred primates express wild‐like behaviors under ecologically relevant conditions, our results underscore the feeding flexibility of the Coquerel's sifaka. Captive wildlife exhibiting the range of species‐specific behaviors are key resources for ecological research and might be best suited for future reintroductions. Research Highlights: Captive Coquerel's sifakas maintained in large forest enclosures at the Duke Lemur Center display ranging and foraging patterns that reflect those of wild sifaka species in western Madagascar. Sifakas occupied 3‐day home ranges of 1.2 ha and spent 26% of their time foraging for a seasonal frugo‐folivorous diet of young and mature leaves, fruits, nuts, flowers, petioles, and bark from minimally 39 plant species. Husbandry efforts can beneficially incorporate ecological research to maintain captive wildlife under conditions that promote animal health while improving research and conservation goals. [ABSTRACT FROM AUTHOR]

The article "Reproductive flexibility in Goodman's mouse lemurs (Microcebus lehilahytsara) at Ankafobe, central highlands" examines the reproductive patterns and flexibility of Goodman's mouse lemurs in various environments in Madagascar. The study reveals that mouse lemurs have different reproductive seasons depending on the individual, species, and location. For instance, grey mouse lemurs can have up to three litters per year in specific habitats. The researchers specifically investigate the reproductive schedules of Goodman's mouse lemurs in Ankafobe, a forest fragment in the central highlands, and collect data from other areas to understand the reproductive patterns of this species. The study reveals seasonal variations in body mass and tail circumference, with a greater range in summer. Juvenile lemurs were found throughout the year, indicating year-round reproduction. The researchers also observed vaginal activity consistent with estrous, pregnant females, and lactating females at different times of the year. These findings suggest that mouse lemurs in Ankafobe have developed reproductive flexibility and metabolic strategies to adapt to the seasonal and unpredictable conditions of their environment. [Extracted from the article]

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This article explores the experiences of two researchers working in Madagascar and their reflections on the challenges and ethical considerations of conducting research in a foreign context. The authors emphasize the importance of humility, curiosity, and collaboration with local communities, and question the role of Western science in Madagascar. They suggest embracing decoloniality by involving local counterparts in research design, respecting local culture and knowledge, and prioritizing the needs and perspectives of local participants. The article also highlights the need for mentorship and inclusion of Malagasy students in research projects to foster diversity in the scientific workforce. [Extracted from the article]

The article discusses the discovery of dwarf lemurs in the Itremo Protected Area in Madagascar, which is managed by the Royal Botanic Gardens Kew. Previous surveys had identified other lemur species in the area, but the presence of dwarf lemurs is a new finding. The researchers conducted trapping and nocturnal surveys to gather more information about the dwarf lemurs and confirm their genetic identity. The article emphasizes the need for further research and conservation efforts in the Itremo Protected Area. Additionally, the article mentions the recolonization of black-and-white ruffed lemurs in a disturbed forest in Ranomafana National Park, challenging the belief that they are always absent from disturbed sites. The researchers fitted GPS collars on three lemurs to monitor their behavior and health. [Extracted from the article]