Bradypus Research Articles

Agonistic interactions in the brown-throated three-toed sloth, Bradypus variegatus (Pilosa: Bradypodidae), in an urban environment in Rio Tinto, Paraiba, Brazil

Agonistic interactions in the brown-throated three-toed sloth, Bradypus variegatus (Pilosa: Bradypodidae), in an urban environment in Rio Tinto, Paraiba, Brazil

The demography of a resource specialist in the tropics: Cecropia trees and the fitness of three-toed sloths.

Resource specialists persist in a narrow range of resources. Consequently, the abundance of key resources should drive vital rates, individual fitness, and population viability. While Neotropical forests feature both high levels of biodiversity and numbers of specialist species, no studies have directly evaluated how the variation of key resources affects the fitness of a tropical specialist. Here, we quantified the effect of key tree species density and forest cover on the fitness of three-toed sloths ( Bradypus variegatus), an arboreal folivore strongly associated with Cecropia trees in Costa Rica, using a multi-year demographic, genetic, and space-use dataset. We found that the density of Cecropia trees was strongly and positively related to both adult survival and reproductive output. A matrix model parametrized with Cecropia-demography relationships suggested positive growth of sloth populations, even at low densities of Cecropia (0.7 trees ha-1). Our study shows the first direct link between the density of a key resource to demographic consequences of a tropical specialist, underscoring the sensitivity of tropical specialists to the loss of a single key resource, but also point to targeted conservation measures to increase that resource. Finally, our study reveals that previously disturbed and regenerating environments can support viable populations of tropical specialists.

PAThs: sulla creazione di un geo-database aperto dedicato all’Egitto tardoantico e medievale

PAThs - Tracking Papyrus and Parchment Paths: An Archaeological Atlas of Coptic Literature (P.I. Paola Buzi) is an ERC Advance project based at the Sapienza University of Rome. It focuses on compiling a catalogue of literary manuscripts in Coptic language, organized by their archaeological and geographical contexts. The Atlas is an open access publishing platform, built on the top of open source technologies and backed up by a web database based on Bradypus system, a MIT licensed RDBMS highly specialized in the management of archaeological and other cultural heritage data. The Atlas and the web database are being constructed to become a linking hub for automated access to the data by third party software and other applications. Specific interconnecting output formats (mainly RDF) are being developed to link this platform to other collaborative systems (such as those developed by Pelagios Commons) utilizing geographical representation, i.e. places, as a common reference point.

The Impact of 'Selfie' Tourism on the Behaviour and Welfare of Brown-Throated Three-Toed Sloths.

Simple SummaryThe use of wild animals as photo props is a potential animal welfare concern that is prevalent across Latin America. The present study documents animal welfare concerns associated with the use of wild caught brown-throated three-toed sloths (Bradypus variegatus) for wildlife ‘selfies’ by tourists at three locations in Manaus, Brazil and Puerto Alegria and Iquitos in Peru. Between 4 October 2016 and 8 April 2017 researchers attended 34 tours, where 17 sloths were observed. The sloths were; (1) held on average by 5 people (during each observation); (2) frequently exposed to physical manipulation of the head and/or limbs; and (3) frequently held by their claws. During handling the sloth’s behaviour was also analysed; we found that the two behaviours performed for the longest average duration of time were surveillance (55.3%) and limb stretching (12.6%). Further validation is needed; however, it is possible that some of the behaviours displayed may be indicators of fear, stress and anxiety. Our results describe behaviours exhibited by sloths, which have previously never been documented in any published literature, the data therefore serves as a potential baseline for future study.The use of wild animals as photo props is prevalent across the globe and is widely recognised to represent a potential animal welfare concern. However, detailed information regarding the specific impacts of such activity on wild animal behaviour is currently lacking. Herein, we investigated how brown-throated three-toed sloths (Bradypus variegatus) were handled by tourists, and how sloths behaved during wildlife ‘selfies’ taken in Manaus, Brazil and Puerto Alegria and Iquitos in Peru. In total, we observed 17 sloths (during 70 focal observations) that were provided for use in wildlife selfies on 34 different tours. We found that an average number of 5 people held each sloth during each focal observation. For 48.6% of the time the sloths were handled in a way which involved physical manipulation of the sloths’ head and/or limbs and/or being held by the claws. From the eight different types of sloth behaviour observed, we found that the two types performed for the longest average duration of time were surveillance (55.3%) and limb stretching (12.6%). Our findings show that when being handled sloths were frequently held in ways that may compromise their welfare. Although to date the behaviour of sloths while being handled has not been reported in any published literature, in this study we document certain behaviours which may act as indicators of compromised welfare. We suggest that our data provides a potential baseline for future study into the behaviour and welfare of sloths.

Digital Cranial Endocasts of the Extinct Sloth Glossotherium robustum (Xenarthra, Mylodontidae) from the Late Pleistocene of Argentina: Description and Comparison with the Extant Sloths

The internal cranial morphology of the terrestrial sloth Glossotherium robustum is described here based on a neurocranium from the late Pleistocene of the Pampean region of Buenos Aires, northeastern Argentina. The first published data on the morphology of the brain cavity of this species date back to the latest nineteenth century. The novel techniques of CT scanning and digital reconstructions enable non-destructive access to the internal cranial features of both extinct and extant vertebrates, and thus improve our knowledge of anatomical features that had previously remained obscure. Therefore, we performed CT scans on the posterior half of a skull of G. robustum and created digital models of the endocasts and internal structures. The results reveal the morphology of the brain cavity itself, as well as the paranasal sinuses and the trajectory of several cranial nerves and blood vessels. These features have been compared with the two extant folivoran genera, the two-toed sloth Choloepus and the three-toed sloth Bradypus. For many characteristics, especially those related to the paranasal pneumaticity and the brain cavity, a closer similarity between Glossotherium and Choloepus is observed, in accordance with the most widely accepted phylogenetic scenarios. However, other features are only shared by the two extant genera, but are probably related to allometric effects and the convergence that affected the two modern lineages. This study, which represents the first exhaustive analysis of digital endocasts of a fossil sloth, reveals the importance of the application of new methodologies, such as CT scans, for elucidating the evolutionary history of this peculiar mammalian clade.

Temporal and spatial resource use by female three-toed sloths and their young in an agricultural landscape in Costa Rica

The information on ecological behavior of wild sloths is very scarce. In this study we determined the home ranges and resources used by three adult female three-toed sloths (Bradypus variegatus) and their four young in an agricultural matrix of cacao (Theobroma cacao), pasture, riparian forests and living fencerows in Costa Rica. Births occurred during November-December and the young became independent at five to seven months of age. Initially, mothers remained fixed in one or a few trees, but expanded their use of resources as young sloths became independent from them. Mothers initially guided the young to preferred food and cover resources, but they gradually left their young in small nucleus areas and colonized new areas for themselves. Home range sizes for young sloths (up to seven months of age) varied between 0.04-0.6 hectares, while home range sizes for mothers varied from 0.04-25.0 hectares. During the maternal care period, 22 tree species were used, with the most common being Cecropia obtusifolia (30.9%), Coussapoa villosa (25.6%), Nectandra salicifolia (12.1%), Pterocarpus officinalis (5.8%) and Samanea saman (5.4%). However, young sloths used only 20 tree species, with the most common being C. villosa (18.4%), S. saman (18.5%) and N. salicifolia (16.7%). The cacao agroforest was used only by mother sloths and never by their young following separation. However, in the riparian forest, both mother sloths and young used the tree species. A total of 28 tree species were used by the mother sloth; including the food species: C. obtusifolia, C. villosa, N. salicifolia and P. officinalis. However, the young used 18 trees species in this habitat with N. salicifolia and S. saman most commonly used, although they rested and fed during the day in C. obtusifolia, C. villosa and O. sinnuata. The cacao agroforest with adjacent riparian forests and fencerows provides an important habitat type that links the smaller secondary forests and other patches.

Q fever epidemic in Cayenne, French Guiana, epidemiologically linked to three-toed sloth.

A Q fever epidemic occurred in 2013 in a small military residential area in Cayenne, French Guiana. A retrospective cohort study was conducted to identify Q fever risk factors. Confirmed acute Q fever case was defined as positive serology (IgM ≥ 50 and phase II IgG ≥ 200) and/or positive qPCR on serum or blood. In addition, wild mammals were captured at the study site and tested by serology and real-time PCR performed on blood, vaginal swabs and ticks. The attack rate was 20 percent (11/54). All the cases were symptomatic with fever >38.5 °C and community-acquired pneumonia for four cases. Log binomial multivariate models identified two independent risk factors associated with Q fever: to clean the house (RRa = 7.5 CI95% [1.03-55.3]) and to carry a three-toed sloth in arms (RRa = 2.6 CI95% [1.1-5.8]). Eighteen marsupial individuals were captured, all PCRs were negative but 17% (3/18) had a positive serology. Another study conducted after the epidemic found only one (1/4) three-tooth sloth (Bradypus tridactylus) with feces highly infectious for C. burnetii MST17. The same strain C. burnetii genotype 17 has been laboratory- confirmed in this mammal and in human cases. These results support the implication of three-toed-sloth in this epidemic. Human contamination mainly occurs through inhalation of infectious aerosols as suggested by high relative risk associated with house cleaning activities and pulmonary forms of the disease, and through direct contact with three- toed-sloth. Positive serological results among marsupials confirm wildlife exposure and suggest a more complex sylvatic transmission cycle among wild mammals.

The environment is a major driver of shape and size variation in widespread extant xenarthrans

Xenarthra is one of the most peculiar mammalian groups to have originated in South America, where most of its evolutionary history has taken place. Xenarthrans have experienced significant climatic changes and also geographical isolation for most of the Cenozoic. Thus, the cranial morphology of xenarthrans may reflect the different pressures that the group is currently undergoing. Our objective is to identify the drivers of phenotypic variation of the skull (both shape and size) in widespread representatives of the superorder Xenarthra throughout South America. We tested the influence of allometry and neutral and niche processes on three extant species, using a geometric morphometric approach: the three-toed sloth Bradypus variegatus, the lesser anteater Tamandua tetradactyla, and the armadillo Dasypus novemcinctus. Our results show that allometry is present, but has a weak effect on shape variation. Geography has a greater impact than allometry in explaining the size variation of T. tetradactyla and the shape of B. variegatus which is, interestingly, the only studied species that follows Bergmann’s rule. Most importantly, the environment drives most of the variation in the shape and size of the three species studied. The responses of B. variegatus and T. tetradactyla to geographical space are congruent with their low mobility and more limited dispersal. The environment mainly affected B. variegatus (e.g., following Bergmann’s rule), probably because of its particularly low metabolism, and D. novemcinctus, due to its high dispersal capacity.

The curious case of Bradypus variegatus sloths: populations in threatened habitats are biodiversity components needing protection

Studying Neotropical wild populations is of particular interest. While this region is facing an escalating habitat degradation, it also has remarkable biodiversity levels, whose origin we are only beginning to understand. A myriad of processes might have had idiosyncratic effects on its numerous species. Within the hottest Neotropical biodiversity hotspot, the Atlantic Forest (AF), species and genetic diversities are organized latitudinally, with decreasing diversity levels southwards. Bradypus variegatus, the brown-throated three-toed sloth, was one of the first species observed to present such pattern. Moreover, within AF, B. variegatus populations seem to be geographically isolated and genetically differentiated. Whether AF B. variegatus isolation, differentiation, and loss of genetic diversity are historical or contemporary (anthropogenic-driven), result from species-specific or general historical events, and if this is of conservation concern remains unclear. Here, we combine micro-evolutionary, multilocus, and high-throughput sequencing approaches to detail the processes responsible for the patterns of genetic diversity on B. variegatus populations in AF, and further understand AF biogeographic history. Few studies made use of similar approaches on Neotropical biodiversity. Our results agree with recent re-interpretations on the AF refugia model and support a species-specific refugium in southern AF, characterized by a metapopulation formation. Finally, we present compelling evidences of the need for conservation actions on AF B. variegatus populations, by comparing genetic diversity levels between populations of different Bradypus species. As far as we know, this is the most comprehensive assessment on Bradypus nuclear DNA diversity.

Architectural Properties of Sloth Forelimb Muscles (Pilosa: Bradypodidae)

Tree sloths have reduced skeletal muscle mass, and yet they are able to perform suspensory behaviors that require both strength and fatigue resistance to suspend their body mass for extended periods of time. The muscle architecture of sloths is hypothesized to be modified in ways that will enhance force production to compensate for this reduction in limb muscle mass. Our objective is to test this hypothesis by quantifying architecture properties in the forelimb musculature of the brown-throated three-toed sloth (Bradypus variegatus: N = 4). We evaluated architecture from 52 forelimb muscles by measuring muscle moment arm (r m), muscle mass (MM), belly length (ML), fascicle length (LF), pennation angle (θ), and physiological cross-sectional area (PCSA), and these metrics were used to estimate isometric force, joint torque, and power. Overall, the musculature becomes progressively more pennate from the extrinsic to intrinsic regions of the forelimb, and the flexors are more well developed than the extensors as predicted. However, most muscles are indicative of a mechanical design for fast joint rotational velocity instead of large joint torque (i.e., strength), although certain large, parallel-fibered shoulder (e.g., m. latissimus dorsi) and elbow (e.g., m. brachioradialis) flexors are capable of producing appreciable torques by having elongated moment arms. This type of functional tradeoff between joint rotational velocity and mechanical advantage is further exemplified by muscle gearing in Bradypus that pairs synergistic muscles with opposing LF/r m ratios in each functional group. These properties are suggested to facilitate the slow, controlled movements in sloths. In addition, the carpal/digital flexors have variable architectural properties, but their collective PCSA and joint torque indicates the capability for maintaining grip force and carpal stability while distributing load from the manus to the shoulder. The observed specializations provide a basis for understanding sustained suspension in sloths.

Tick fauna of wild animals received and attended at the Santarém Zoological Park, western Pará State, Brazil

ABSTRACT: Ticks are known worldwide for parasitizing a number of wild hosts. However, few studies have been conducted on ticks in zoos in Brazil. The objective of the present study was to collect, identify, and report the parasitic tick fauna found on wild Amazon animals received and attended at the Santarém Zoological Park from September 2004 to September 2013. In all, 56 animals, including 26 mammals and 30 reptiles, were sampled, from which 1172 ticks were collected and identified, comprising 862 adults, 284 nymphs, and 26 larvae. Nymphs of Amblyomma geayi on three-toed sloth (Bradypus tridactylus), adults of Amblyomma longirostre on black dwarf porcupine (Coendou nycthemera), and nymphs of Amblyomma naponense on southern tamandua (Tamandua tetradactyla) were identified for the first time in the country in the present study. Although, the North region is the largest among the five Brazilian regions, this is the first study conducted with ticks and animals attended in a zoo in the Brazilian Amazon.

Céstodos de Vertebrados VI

In the present contribution, concerning cestodes; a new host for Moniezia benedeni (Moniez, 1874) Blanchard, 1891, is registered as Bradypus griseus griseus (Gray, 1871) Allen, 1891 (perezoso) from Costa Rica, Central America. Species of the genus Moniezia, as reported in previous publications have been reduced to synonymies on the basis of the nature of their interproglot­tidial glands. We are in agremeent with the importance of this character, together with the morphology and structure of the vitellaria and ovary in the determination of this genus and very specially as characters to be considered for the differentiation of Moniezia Blanchard, 1891 and Cittotaenia Riehm, 1891 which are so close phylogenetically as to be easily confused, DOUTHITT (7). Tetrabothrus sulae (Baird, 1853) Baer, 1954, collected from a pelican (Pelecanus occidentalis carolinensis Gmelin) in the state of Veracruz, has been determined on the basis, of the character of the cirrus and pouch, the vagina, the scolex and the number of testes, as given in BAER'S 1954 monograph of species of the family Tetrabothridae. Two taeniae collected from Urocyon cinereoargenteus costarricensis and Felis weidii nicaraguae, have been determined only tentatively as Taenia laticollis Rudolphi, 1819 and Taenia taeniaeformisis (Batsch, 1786) Wolffughel, 1911 pend­ing a study of their larval phase. The larval stage is not always available and we suggest that a study of the size and structure of the hooks is absolutely essential for precise identification of these cestodes as well as the anatomy of gravid proglotids and mature segments, but unless the characters of the organs in this segment present specifical features, like the sphincter in the vagina of Taenia taeniaeformis (14), the morphology of mature proglotids should be placed in second place. We suggest also, that a histological study should be made at the same time as the morphological, in order to see the structural details and make specific diagnoses more precise.

Cophylogenetics and biogeography reveal a coevolved relationship between sloths and their symbiont algae

Specialized species, like arboreal folivores, often develop beneficial relationships with symbionts to exploit ecologically constrained lifestyles. Although coevolution can drive speciation by specialization of a symbiont to a host, a symbiotic relationship is not indicative of coevolution between host and symbiont. We tested for coevolved relationships between highly specialized two- and three-toed sloths (Choloepus spp. and Bradypus spp., respectively) and their symbiotic algae using cophylogenies and phylogeography. Our phylogeographic analysis showed a biogeographic pattern for the sloth distribution that was not found in the algal phylogeny. We found support for congruence between the sloth and algae phylogenies, implying cospeciation, only in the Bradypus lineage. Algae host-switching occurred from Bradypus spp. to Choloepus spp. Our results support a previously hypothesized symbiotic relationship between sloths and the algae in their fur and indicate that coevolution may have played a role in algae diversification. More broadly, convergent evolution may facilitate host switching between deeply diverged host lineages.

Sloths in the city: unexpectedly high density of pale-throated three-toed sloths (Bradypus tridactylus) found in an urban forest patch in Paramaribo, Suriname

Sloths in the city: unexpectedly high density of pale-throated three-toed sloths (Bradypus tridactylus) found in an urban forest patch in Paramaribo, Suriname

Four new reports of mammal species from Tayrona National Park, Colombia

This protected area is one of the most visited in the country. However, information regarding basic biodiversity inventories and especially for mammals is scarce (Jimenez-Alvarado et al. 2015). We present the first record for four species at TNP: porcupine (Coendou sp.), Brown-eared Woolly Opossum (Caluromys lanatus), Three-toed Sloth (Bradypus variegatus) and Neotropical otter (Lontra longicaudis). Reports came from sporadic encounters with park rangers and with the localcommunity during 2014 and 2015. All individuals were juveniles and were found in different sectors in TNP

Arboreal Folivores Limit Their Energetic Output, All the Way to Slothfulness.

By exploiting unutilized resources, organisms expand into novel niches, which can lead to adaptive radiation. However, some groups fail to diversify despite the apparent opportunity to do so. Although arising multiple times, arboreal folivores are rare and have not radiated, presumably because of energetic constraints. To explore this hypothesis, we quantified the field metabolic rate (FMR), movement, and body temperature for syntopic two- and three-toed sloths, extreme arboreal folivores that differ in their degree of specialization. Both species expended little energy, but three-toed sloths (162 kJ/day*kg(0.734)) possessed the lowest FMR recorded for any mammal. Three-toed sloths were more heterothermic and moved less than two-toed sloths. We then compared FMRs and basal metabolic rates (BMRs) for 19 species of arboreal folivores along a spectrum of specialization. Overall, arboreal folivores had lower BMRs and FMRs than other mammals, and increasing specialization led to lower FMRs but not BMRs. Thus, reduced energetic expenditure in specialized species was the result of thermoregulatory and behavioral strategies, rather than simply a proportionate reduction in BMR. Altogether, our findings support the concept that arboreal folivores are tightly constrained by nutritional energetics and help to explain the lack of radiation among species exploiting a lifestyle in the trees.

Evolutionary Relationships among Extinct and Extant Sloths: The Evidence of Mitogenomes and Retroviruses.

Macroevolutionary trends exhibited by retroviruses are complex and not entirely understood. The sloth endogenized foamy-like retrovirus (SloEFV), which demonstrates incongruence in virus–host evolution among extant sloths (Order Folivora), has not been investigated heretofore in any extinct sloth lineages and its premodern history within folivorans is therefore unknown. Determining retroviral coevolutionary trends requires a robust phylogeny of the viral host, but the highly reduced modern sloth fauna (6 species in 2 genera) does not adequately represent what was once a highly diversified clade (∼100 genera) of placental mammals. At present, the amount of molecular data available for extinct sloth taxa is limited, and analytical results based on these data tend to conflict with phylogenetic inferences made on the basis of morphological studies. To augment the molecular data set, we applied hybridization capture and next-generation Illumina sequencing to two extinct and three extant sloth species to retrieve full mitochondrial genomes (mitogenomes) from the hosts and the polymerase gene of SloEFV. The results produced a fully resolved and well-supported phylogeny that supports dividing crown families into two major clades: 1) The three-toed sloth, Bradypus, and Nothrotheriidae and 2) Megalonychidae, including the two-toed sloth, Choloepus, and Mylodontidae. Our calibrated time tree indicates that the Miocene epoch (23.5 Ma), particularly its earlier part, was an important interval for folivoran diversification. Both extant and extinct sloths demonstrate multiple complex invasions of SloEFV into the ancestral sloth germline followed by subsequent introgressions across different sloth lineages. Thus, sloth mitogenome and SloEFV evolution occurred separately and in parallel among sloths.

Tar Pits

Tar Pits George Bilgere (bio) The last time I saw my fatherwas at the La Brea Tar Pitsa year after the divorce. He was still living in St. Louis,running the businessto the bottomof a fifth of Jim Beam. In my mind’s eyehe is a specimen, a fetusof a father, floating in a jarin some roadside museum. I was nine. We had nothingto say, so he took meto the La Brea Tar Pits, asdivorced fathers do. He was a membraneat that point.An effigy tremblingin another man’s suit. We staredat the three-toed sloth,the dire wolf with itsmarble eyes. My father, I wishyou could rise from thatblack pit and emerge into light, like the tigerwe saw that day,sheathed again in muscle,its great teeth like sabers. [End Page 485] George Bilgere GEORGE BILGERE’s most recent collection of poetry is Imperial (University of Pittsburgh Press, 2014). His work is familiar to National Public Radio audiences through his frequent appearances on Garrison Keillor’s The Writer’s Almanac. He has received grants and fellowships from the NEA, the Pushcart Foundation, the Witter Bynner Foundation, and the Ohio Arts Council. He lives and teaches in Cleveland, Ohio, which has made him hardy and resolute. Copyright © 2016 George Bilgere

Diet specialization selects for an unusual and simplified gut microbiota in two- and three-toed sloths.

Symbiotic microbial communities are critical to the function and survival of animals. This relationship is obligatory for herbivores that engage gut microorganisms for the conversion of dietary plant materials into nutrients such as short-chain organic acids (SCOAs). The constraint on body size imposed by their arboreal lifestyle is thought to make this symbiosis especially important for sloths. Here, we use next-generation sequencing to identify the bacteria present in the fore and distal guts of wild two- and three-toed sloths, and correlate these communities with both diet and SCOAs. We show that, unlike other mammalian herbivores, sloth gut communities are dominated by the bacterial phyla Proteobacteria and Firmicutes. Specifically, three-toed sloths possess a highly conserved, low-diversity foregut community with a highly abundant Neisseria species associated with foregut lactate. In contrast, two-toed sloths have a more variable and diverse foregut microbiota correlated with a variety of SCOAs. These differences support the hypothesis that feeding behaviour selects for specific gut bacterial communities, as three-toed sloths subsist primarily on Cecropia tree leaves while two-toed sloths have a more generalist diet. The less diverse diet and gut microbiota of three-toed sloths may render them more susceptible to habitat loss and other diet-altering conditions.

Activity budget, pattern and rhythm of maned sloths (Bradypus torquatus): Responses to variations in ambient temperature

Three-toed sloths (Bradypus) are heterothermic, and ambient temperature may have a direct effect on their activity levels. Our goal was to describe the time budget, pattern and rhythm of activity of the maned sloth, Bradypus torquatus (Xenarthra: Bradypodidae), and to evaluate the effect of ambient temperature on its activity. We hypothesized that (1) sloth activity increases with ambient temperature, fluctuating with the circadian temperature cycle, and (2) sloths are more active in the diurnal period during colder seasons than warm seasons due to constraints or avoidance of the colder times within a 24-h cycle. Nine radio-collared individuals were followed in forest remnants in southern Bahia, Brazil from March 2003 to April 2014. Behavior data of 8 sloths were collected during the diurnal period by direct visualization (608h of record), and the activities of 4 sloths were recorded by an automated system during continuous hours (744h of record). The maned sloths exhibited low activity levels, resting 77% of a 24-h period. In general, they were cathemeral, although they were twice as active in the diurnal phase (active 32% of the time) compared with the nocturnal phase (15%). The ambient temperature had a significant positive effect on activity levels. The rhythm of activity was circadian and synchronized with the ambient temperature. No difference was detected in the diurnal activity between hotter and colder seasons, most likely reflecting the low fluctuations in climatic conditions of this tropical forest. The narrow relationship between the circadian activity pattern of maned sloths and the ambient temperature cycle highlights their poor thermoregulatory ability. The lower activity levels exhibited during colder times may represent a behavioral adaptation that reduces heat loss, enhances body temperature control and optimizes energetic benefits, a key feature for a species relying on a low energetic diet.