DOCSLIB.ORG

An Update on the Physiology of Two- and Three-Toed Sloths

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
An Update on the Physiology of Two- and Three-Toed Sloths Brazilian Journal of Medical and Biological Research (2000) 33: 129-146 Physiology of sloths 129 ISSN 0100-879X An update on the physiology of two- and three-toed sloths D.P. Gilmore2, 1Departamento de Fisiologia e Farmacologia, C.P. Da-Costa1 and Universidade Federal de Pernambuco, Recife, PE, Brasil D.P.F. Duarte1 2Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, UK Abstract Correspondence Physiological and pharmacological research undertaken on sloths Key words C.P. Da-Costa during the past 30 years is comprehensively reviewed. This includes · Xenarthra Departamento de Fisiologia e the numerous studies carried out upon the respiratory and cardiovas- · Sloths Farmacologia, UFPE · cular systems, anesthesia, blood chemistry, neuromuscular responses, Bradypus 50670-901 Recife, PE · Choloepus the brain and spinal cord, vision, sleeping and waking, water balance Brasil · Physiology Fax: +55-81-271-8350 and kidney function and reproduction. Similarities and differences E-mail: [email protected] between the physiology of sloths and that of other mammals are discussed in detail. Research supported by CNPq and FACEPE. D.P. Gilmore is the recipient of a Royal Society and Brazilian Academy of Sciences Introduction tion has been proposed (3), which places the international exchange fellowship. two-toed sloths in the family Megalonychidae It is almost 30 years since Goffart (1) and the three-toed sloths in the family published Function and Form in the Sloth Bradypodidae. It is thus now generally be- Received March 31, 1999 and in the time that has now elapsed there lieved that the two living families of sloths Accepted October 14, 1999 has been no further comprehensive evalua- have quite different phylogenetic origins and tion of the biology of this mammal. It is the that Bradypus is derived from megatheroid intention of the present review to bring to- and Choloepus from megalonychid sloths, gether research reports of physiological and their separate evolution beginning about 35 pharmacological studies that have appeared million years ago in the late Oligocene. since 1971 and thereby update our knowl- The distribution of two- and three-toed edge about this intriguing animal. sloths in South America is illustrated in Fig- Sloths are included, along with the arma- ures 1A and B. Bradypus variegatus, the dillos and anteaters, in the Order Xenarthra brown-throated three-toed sloth, is one of (Edentata). Analysis of amino acid sequences the most common medium-sized mammals of the eye lens proteins (2) has confirmed in the tropical forests of Central and South earlier anatomical evidence indicating that America. Previously many workers have re- the xenarthrans are an old offshoot of the ferred to the species as Bradypus tridactylus eutherian stem that arose at least 75-80 mil- but this, the pale-throated three-toed sloth, is lion years ago. Initially all present-day sloths now regarded as the one found only in south- were considered to belong to the family ern Venezuela, the Guianas and northern Bradypodidae with two genera, Bradypus Brazil south to the Rio Amazonas. Through- and Choloepus. However, a new classifica- out this review an attempt has been made to Braz J Med Biol Res 33(2) 2000 130 D.P. Gilmore et al. distinguish between the misnamed Brady- from 32.7o to 35.5oC (4). In most, their basal pus tridactylus = variegatus and the rightful metabolic rates lie between 40 and 60% of bearer of the title. those expected from their mass on the basis All xenarthrans have low body tempera- of Kleibers rule and in the case of the tree tures compared to other mammals, ranging sloths may be directly related to the reduc- tion in muscle mass correlated with their Figure 1 - Distribution of two- A sedentary lifestyle (4). The type of food con- and three-toed sloths through- sumed would also appear to be influential in out Central and South America C. hoffmanni (A, B) (for further details see Choloepus setting the low basal metabolic rates in Wetzel (3)). xenarthrans for, firstly, the food of sloths has a low energy content and, secondly, it may C. didactylus contain poisonous compounds that require a low rate of absorption for adequate detoxifi- cation (4). The low body temperature of both Bradypus and Choloepus, which varies with that of their surroundings, is a major factor restricting their distribution. Goffart (1) dis- cussed thermoregulation in the sloth in de- tail. More recently, Silva et al. (5) recorded rectal temperatures in five adult male sloths (Bradypus variegatus) at four-hour intervals over six days. They observed a circadian rhythm in body temperature (ranging from 28o to 35oC), which was closely correlated with changes in environmental temperature. In cold conditions sloths are poor regulators of body temperature because they have little B ability to increase their metabolism due to their small muscle masses. Thus neither Bra- Bradypus dypus nor Choloepus are able to tolerate cool temperate latitudes. Bradypus has a B. tridactylus lower thermal conductance than Choloepus because only the former has a dense woolly undercoat below the coarse guard hairs, and Bradypus also has a lower limit of B. variegatus thermoneutrality (24oC) than does Choloe- pus (18oC). B. torquatus Respiratory and cardiovascular systems The normal respiratory rate in Choloepus hoffmanni when sleeping has been reported to be 13 per minute (range 10-18), decreas- ing when the rectal temperature exceeded 37oC (6). In captive sloths, with an ambient temperature of 30oC, the respiratory rate was Braz J Med Biol Res 33(2) 2000 Physiology of sloths 131 found to be dependent upon the animals capacity: tidal volume 13.5 ± 3.4%, inspira- state. Excited or agitated sloths have been tory reserve volume 52.6 ± 8.9%, expiratory noted to breathe at a rate of between 10 and reserve volume 9.7 ± 4.7%, residual volume 30 per minute (7). In awake, but inactive, 24.2 ± 6.8%. Inspiratory capacity was 66.1 ± sloths in captivity the breathing rate was 6.6%, vital capacity 75.8 ± 6.8% and func- found to be 46 (range 38-52) breaths per tional residual capacity 33.9 ± 6.6%. In an- minute (6) and in awake and active animals other study (13) the same group analyzed the it was 73 (range 65-78). For both free-roam- active mechanical properties of these ani- ing and captive sloths in Panama, a resting mals lungs and recorded the following: rate of nine breaths per minute (range 8-11) (mean ± SD) 0.33 ± 0.10 cmH2O/l and 0.09 has been reported (6). Respiration and heart ± 0.02 cmH2O/l for resistance and active rates in anesthetized two-toed sloths (Cho- elasticity of the respiratory system. Other loepus didactylus) were 18-48 breaths per research (14) into the passive mechanical minute and 48-108 beats per minute (bpm), properties of the lung and thoracic wall in respectively (8). Félix et al. (9) carried out three-toed sloths (Bradypus variegatus) re- studies on the airway flow and pulmonary corded the following values (mean ± SD) of ventilation of Bradypus variegatus anesthe- 0.183 ± 0.030 cmH2O/ml for passive elastic- tized with sodium pentobarbital, but breath- ity of the respiratory system, 0.045 ± 0.002 ing spontaneously. They reported that the cmH2O/ml for passive elasticity of the pul- tidal volume was 57.6 ± 14.4 ml, the inspira- monary system and 0.134 ± 0.024 cmH2O/ tion time 3.8 ± 0.4 s and the expiration time ml for the thoracic wall, respectively. Active 15.9 ± 0.7 s for a respiratory rate of 3.0 ± 0.8 elasticity and active resistance were found to breaths per minute. Respiratory minute vol- be 13 and 56% higher, respectively, than the ume was 181.3 ± 27.9 ml and the expiratory passive counterparts. pause 13.1 ± 6.8 s. This long respiratory The size of the heart is adapted to the pause observed in the anesthetized animal quiet life of the sloth, but it is by no means was also noted by Santos et al. (10), who responsible for the inability of these animals monitored the breathing of four freely mov- to undertake sustained speedy movement. ing sloths (Bradypus variegatus) in the labo- The heart rate of Bradypus was initially re- ratory using an impedance technique. These ported (7) to range from 60 to 110 bpm, with animals were kept at a constant room tem- that of Choloepus being somewhat higher perature of 26oC for a period of 24 h in a 12- (70-130 bpm). A great deal more informa- h light/12-h dark cycle. The respiratory rate tion has since been obtained on cardiovascu- was 8.6 ± 5.3 breaths per minute (range 4.9- lar function in the sloth, mainly from the 20.6). Breathing was slowest at 11.30 h and group working at the Federal University of most rapid at 2.30 h when there was an Pernambuco in Recife. Research there (15, associated increase in the animals motor 16) on Bradypus tridactylus = variegatus, activity. In other data obtained recently (11), under pentobarbital anesthesia, found heart over a 2-h period from freely roaming sloths rates of 91 ± 4.5 bpm and 94.1 ± 3.3 bpm, in the laboratory at 26oC, the respiratory rate respectively. Another study (17) demon- was found to be 6.1 ± 0.81 breaths per minute strated similar values (91 bpm) in sloths and the expiratory part of the cycle 71%. under chloralose anesthesia. In conscious, Aguiar et al. (12) also determined pulmo- but restrained cannulated sloths (Bradypus nary volume and capacity in eight three-toed tridactylus = variegatus) heart rates of 89.7 sloths (Bradypus variegatus) under sodium ± 9.7 bpm were measured (16).
Load more

Recommended publications
  • Xenarthrans: 'Aliens'
    Vet Times The website for the veterinary profession https://www.vettimes.co.uk XENARTHRANS: ‘ALIENS’ ON EARTH Author : JONATHAN CRACKNELL Categories : Vets Date : August 4, 2008 JONATHAN CRACKNELL finds that hanging around with sloths and their fellow Xenarthrans offers up exciting challenges XENARTHRANS: the name sounds like a race from a low-budget science fiction film. This is actually a super-order of mammals that get their name from their “alien” joint, which is exhibited in the vertebral joints. The Xenarthrans include 31 living species: six species of sloth, four anteaters and 21 species of armadillos – all of which originated in South America. Historically, these animals were classified within the order Edentata (meaning “without teeth”), which included pangolins and aardvarks. It was realised that this was a polyphyletic group, containing unrelated families. Therefore, the Xenarthra order was created. The Xenarthrans are a well-represented order in captivity, with banded armadillos (Dasypus novemcinctus) becoming one of the new “exotic” exotics to be presented to clinicians. In zoological collections, giant anteaters (Myrmecophaga tridactyla), southern tamanduas (Tamandua tetradactyla), and sloths (typically the southern two-toed sloth – Choloepus didactylus – although others are present) are among the more common species housed in captivity. Every species has its own needs and oddities. With this brief review of each species, the author will look at basic anatomy and physiology, along with a quick review of some of the more commonly reported complaints for this group of animals. 1 / 14 Giant anteater The giant anteater’s most obvious feature is its long tongue and bushy tail. They are approximately 1.5 to two metres long and weigh in the region of 18kg to 45kg.
    [Show full text]
  • Introduction Recent Classifications Regard the Order Pilosa, Anteaters
    Introduction Recent classifications regard the order Pilosa, anteaters and sloths, and order Cingulata, the armadillos, within the superorder Xenarthra meaning “strange joints”. In the past, Pilosa and Cingulata wer regarded as suborders of the order Xenarthra, with the armadillos. Earlier still, both armadillos and pilosans were classified together with pangolins and the aardvark as the order Edentata meaning “toothless”. The orders Pilosa and Cingulata are distinguishable as the cingulatas have an armoured upper body and the pilosa have fur. Studies have concluded that sloths, anteaters, and armadillos diverged at least 75-80 million years ago and that they are as different from one another as are carnivores, bats and primates. The Pilosa are now considered almost exclusively a New World order, however, fossil records indicate that they were once found in Europe and possibly Asia. This order may have been distributed worldwide in the Cretaceous period, but became limited to South America and have remained there for most of their history and evolved into numerous groups. The Pilosa were once far more diverse than they are today; there are known to be 10 times as many fossil as living genera. The superorder is distinguished from all others by what are known as the xenarthrous vertebrae. There are secondary and sometimes even more, articulations between the vertebrae of the lumbar (lower back) series. In other words, consecutive vertebrae connect in more than one place. In addition, the pelvis connects with more of the spine than in other mammals. These adaptations to the spine give support, particularly to the hips. The name Xenarthra refers to this peculiarity of the spine and modem taxonomy places these three groups of animals together, even though they are very different from one another and they are highly specialized.
    [Show full text]
  • Michael O. Woodburne1,* Alberto L. Cione2,**, and Eduardo P. Tonni2,***
    Woodburne, M.O.; Cione, A.L.; and Tonni, E.P., 2006, Central American provincialism and the 73 Great American Biotic Interchange, in Carranza-Castañeda, Óscar, and Lindsay, E.H., eds., Ad- vances in late Tertiary vertebrate paleontology in Mexico and the Great American Biotic In- terchange: Universidad Nacional Autónoma de México, Instituto de Geología and Centro de Geociencias, Publicación Especial 4, p. 73–101. CENTRAL AMERICAN PROVINCIALISM AND THE GREAT AMERICAN BIOTIC INTERCHANGE Michael O. Woodburne1,* Alberto L. Cione2,**, and Eduardo P. Tonni2,*** ABSTRACT The age and phyletic context of mammals that dispersed between North and South America during the past 9 m.y. is summarized. The presence of a Central American province of cladogenesis and faunal differentiation is explored. One apparent aspect of such a province is to delay dispersals of some taxa northward from Mexico into the continental United States, largely during the Blancan. Examples are recognized among the various xenar- thrans, and cervid artiodactyls. Whereas the concept of a Central American province has been mentioned in past investigations it is upgraded here. Paratoceras (protoceratid artio- dactyl) and rhynchotheriine proboscideans provide perhaps the most compelling examples of Central American cladogenesis (late Arikareean to early Barstovian and Hemphillian to Rancholabrean, respectively), but this category includes Hemphillian sigmodontine rodents, and perhaps a variety of carnivores and ungulates from Honduras in the medial Miocene, as well as peccaries and equids from Mexico. For South America, Mexican canids and hy- drochoerid rodents may have had an earlier development in Mexico. Remarkably, the first South American immigrants to Mexico (after the Miocene heralds; the xenarthrans Plaina and Glossotherium) apparently dispersed northward at the same time as the first Holarctic taxa dispersed to South America (sigmodontine rodents and the tayassuid artiodactyls).
    [Show full text]
  • Proving: Two-Toed Sloth (Choloepus Didactylus) Date: October 2017 by Mani Norland, Luke Norland & the School of Homeopathy
    Orchard Leigh · Rodborough Hill · Stroud · Gloucestershire · GL5 3SS T: +44 (0)1453 765 956 · E: [email protected] www.homeopathyschool.com Proving: Two-toed Sloth (Choloepus didactylus) Date: October 2017 By Mani Norland, Luke Norland & The School of Homeopathy. The Homeopathic Proving of Choloepus didactylus 2 Latin Name Choloepus didactylus. Common Names Two-toed sloth. Hoffmann's two-toed sloth. Linnaeus's two-toed sloth. Taxonomy Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Pilosa Suborder: Folivora Family: Choloepodidae Genus: Choloepus Sophia Müller, Unsplash(1) About (1, 2) The remedy was prepared from a hair sample and run-up to the 30th centesimal potency by the proving group led by Mani Norland and John Morgan. There were 13 female and 2 male provers; each taking a single dose. The proving was fully supervised for a period of 2 months. The diaries were then collated and repertorised by Luke Norland. Whilst the name "sloth" means lazy or idle, the slow movements of this mammal are a useful adaptation for surviving on a low-energy diet of leaves. They are so solitary in their nature that it is even uncommon for two to be found together in the same tree. The sloth spends almost its entire life, including eating, sleeping, mating, and giving birth, hanging upside down from tree branches. However, when the time comes for urination and defecation they slowly make their way to the ground. This seems to be rather a behavioural quirk, as whilst earthbound they are almost defenceless. Their shaggy coat has grooved hair which plays host to a symbiotic green algae, providing both camouflage and nutrients.
    [Show full text]
  • Taphonomy and Significance of Jefferson's Ground Sloth (Xenarthra: Megalonychidae) from Utah
    Western North American Naturalist Volume 61 Number 1 Article 9 1-29-2001 Taphonomy and significance of Jefferson's ground sloth (Xenarthra: Megalonychidae) from Utah H. Gregory McDonald Hagerman Fossil Beds National Monument, Hagerman, Idaho Wade E. Miller Thomas H. Morris Follow this and additional works at: https://scholarsarchive.byu.edu/wnan Recommended Citation McDonald, H. Gregory; Miller, Wade E.; and Morris, Thomas H. (2001) "Taphonomy and significance of Jefferson's ground sloth (Xenarthra: Megalonychidae) from Utah," Western North American Naturalist: Vol. 61 : No. 1 , Article 9. Available at: https://scholarsarchive.byu.edu/wnan/vol61/iss1/9 This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Western North American Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Western North American Naturalist 61(1), © 2001, pp. 64–77 TAPHONOMY AND SIGNIFICANCE OF JEFFERSON’S GROUND SLOTH (XENARTHRA: MEGALONYCHIDAE) FROM UTAH H. Gregory McDonald1, Wade E. Miller2, and Thomas H. Morris2 ABSTRACT.—While a variety of mammalian megafauna have been recovered from sediments associated with Lake Bonneville, Utah, sloths have been notably rare. Three species of ground sloth, Megalonyx jeffersonii, Paramylodon har- lani, and Nothrotheriops shastensis, are known from the western United States during the Pleistocene. Yet all 3 are rare in the Great Basin, and the few existing records are from localities on the basin margin. The recent discovery of a partial skeleton of Megalonyx jeffersonii at Point-of-the-Mountain, Salt Lake County, Utah, fits this pattern and adds to our understanding of the distribution and ecology of this extinct species.
    [Show full text]
  • Xenarthra: Megatheriidae) Were in Chile?: New Evidences from the Bahía Inglesa Formation, with a Reappraisal of Their Biochronological Affinities
    Andean Geology ISSN: 0718-7092 ISSN: 0718-7106 [email protected] Servicio Nacional de Geología y Minería Chile How many species of the aquatic sloth Thalassocnus (Xenarthra: Megatheriidae) were in Chile?: new evidences from the Bahía Inglesa Formation, with a reappraisal of their biochronological affinities Peralta-Prat, Javiera; Solórzano, Andrés How many species of the aquatic sloth Thalassocnus (Xenarthra: Megatheriidae) were in Chile?: new evidences from the Bahía Inglesa Formation, with a reappraisal of their biochronological affinities Andean Geology, vol. 46, no. 3, 2019 Servicio Nacional de Geología y Minería, Chile Available in: https://www.redalyc.org/articulo.oa?id=173961656010 This work is licensed under Creative Commons Attribution 3.0 International. PDF generated from XML JATS4R by Redalyc Project academic non-profit, developed under the open access initiative Javiera Peralta-Prat, et al. How many species of the aquatic sloth Thalassocnus (Xenarthra: Megath... Paleontological Note How many species of the aquatic sloth alassocnus (Xenarthra: Megatheriidae) were in Chile?: new evidences from the Bahía Inglesa Formation, with a reappraisal of their biochronological affinities ¿Cuántas especies del perezoso acuático alassocnus (Xenarthra: Megatheriidae) existieron en Chile?: nuevas evidencias de la Formación Bahía Inglesa, con una revisión de sus afinidades biocronológicas. Javiera Peralta-Prat 1 Redalyc: https://www.redalyc.org/articulo.oa? Universidad de Concepción, Chile id=173961656010 [email protected] Andrés Solórzano *2 Universidad de Concepción, Chile [email protected] Received: 13 July 2018 Accepted: 27 November 2018 Published: 04 February 2019 Abstract: e aquatic sloth, alassocnus, is one of the most intriguing lineage of mammal known from the southern pacific coast of South America during the late Neogene.
    [Show full text]
  • Mammals at Woodland Park Zoo Pre-Visit Information
    Mammals at Woodland Park Zoo Pre-visit Information If you are planning a zoo field trip and wish to have your students focus on mammals during their visit, this pre- visit sheet can help them get the most out of their time at the zoo. We have put together an overview of key concepts related to mammals, a list of basic vocabulary words, and a checklist of mammal species at Woodland Park Zoo. Knowledge and understanding of these main ideas will enhance your students’ zoo visit. OVERVIEW: There are over 5,000 species of mammals currently identified worldwide, inhabiting a number of different biomes and exhibiting a range of adaptations. Woodland Park Zoo exhibits a wide variety of mammal species (see attached checklist) in several different areas of the zoo. A mammal field trip to the zoo could focus on the characteristics of mammals (see “Concepts” below), comparing/contrasting different mammals or learning about biomes and observing the physical characteristics of mammals in different biomes. CONCEPTS: Mammals share the following physical characteristics: • Fur or hair • Endothermic, often called warm-blooded. Endothermic animals maintain a constant internal body temperature rather than adjusting to the temperature of their surroundings as ectothermic animals (such as reptiles and amphibians) do. • Mammary glands, which are used to feed milk to young Mammals, like all plants and animals, have five basic needs to survive—food, water, shelter, air and space. They inhabit every continent on the planet and range in size from Kitti’s hog-nosed bat (also called bumblebee bat) at 0.07 ounces (2 grams) to the blue whale at 100 tons (approximately 90,000 kilograms).
    [Show full text]
  • IUCN SSC Anteater, Sloth and Armadillo Specialist Group
    IUCN SSC Anteater, Sloth and Armadillo Specialist Group 2019 Report Mariella Superina Chair Mission statement Plan Mariella Superina (1) The mission of the IUCN SSC Anteater, Sloth and Planning: plan for protection of Brazilian Three- Armadillo Specialist Group is to promote the banded Armadillo and Pygmy Three-toed Sloth. Red List Authority Coordinator long-term conservation of the extant species of Act Agustín M. Abba (2) xenarthrans (anteaters, sloths and armadillos) Conservation actions: effective protection of and their habitats. Brazilian Three-banded Armadillo and Pygmy Location/Affiliation Three-toed Sloth. (1) IMBECU - CCT CONICET Mendoza, Mendoza, Projected impact for the 2017-2020 Network quadrennium Argentina Capacity building: (1) teach five training courses; (2) CEPAVE, La Plata, Argentina By the end of 2020, we envision the Anteater, (2) train Argentinean mammalogists in Red List Sloth and Armadillo Specialist Group (ASASG) assessments. Number of members will have achieved increased protection for Proposal development and funding: secure 26 our priority species, the Critically Endangered funding to replenish the Xenarthra Conserva- Pygmy Three-toed Sloth (Bradypus pygmaeus) tion Fund. Social networks and the Vulnerable Brazilian Three-banded Synergy: enter into partnership with zoological Armadillo (Tolypeutes tricinctus). We aim to Facebook: institutions. IUCN/SSC Anteater, Sloth and Armadillo reach this goal by increasing scientific knowl- Communicate Specialist Group edge, raising awareness, developing and imple- Communication: (1) publish four issues of the Website: www.xenarthrans.org menting comprehensive action plans and securing protection of their habitat. Capacity ASASG Newsletter; (2) increase awareness building through training courses will allow us to through campaigns at zoos and other institu- increase the number of researchers dedicated tions; (3) increase awareness for Xenarthra.
    [Show full text]
  • Palaeoproteomics Resolves Sloth Relationships
    ARTICLES https://doi.org/10.1038/s41559-019-0909-z Palaeoproteomics resolves sloth relationships Samantha Presslee1,2,3,24, Graham J. Slater4,24, François Pujos5, Analía M. Forasiepi5, Roman Fischer 6, Kelly Molloy7, Meaghan Mackie3,8, Jesper V. Olsen 8, Alejandro Kramarz9, Matías Taglioretti10, Fernando Scaglia10, Maximiliano Lezcano11, José Luis Lanata 11, John Southon12, Robert Feranec13, Jonathan Bloch14, Adam Hajduk15, Fabiana M. Martin16, Rodolfo Salas Gismondi 17, Marcelo Reguero18, Christian de Muizon19, Alex Greenwood20,21, Brian T. Chait 7, Kirsty Penkman22, Matthew Collins3,23 and Ross D. E. MacPhee2* The living tree sloths Choloepus and Bradypus are the only remaining members of Folivora, a major xenarthran radiation that occupied a wide range of habitats in many parts of the western hemisphere during the Cenozoic, including both continents and the West Indies. Ancient DNA evidence has played only a minor role in folivoran systematics, as most sloths lived in places not conducive to genomic preservation. Here we utilize collagen sequence information, both separately and in combination with published mitochondrial DNA evidence, to assess the relationships of tree sloths and their extinct relatives. Results from phylo- genetic analysis of these datasets differ substantially from morphology-based concepts: Choloepus groups with Mylodontidae, not Megalonychidae; Bradypus and Megalonyx pair together as megatherioids, while monophyletic Antillean sloths may be sister to all other folivorans. Divergence estimates are consistent with fossil evidence for mid-Cenozoic presence of sloths in the West Indies and an early Miocene radiation in South America. he sloths (Xenarthra, Folivora), nowadays a taxonomically consensus8–10,16,17 in morphology-based phylogenetic treatments is narrow (six species in two genera) component of the fauna of to place the three-toed sloth as sister to all other folivorans (Fig.
    [Show full text]
  • Informes Individuales IUCN 2018.Indd
    IUCN SSC Anteater, Sloth and Armadillo Specialist Group 2018 Report Mariella Superina Chair Mission statement Three-banded Armadillo and the Pygmy Mariella Superina (1) The mission of the IUCN SSC Anteater, Sloth and Three-toed Sloth. Armadillo Specialist Group is to promote the Act Red List Authority Coordinator long-term conservation of the extant species of Conservation actions: effective protection for Agustín M. Abba (2) xenarthrans (anteaters, sloths and armadillos) the Brazilian Three-banded Armadillo and the and their habitats. Pygmy Three-toed Sloth. Location/Affiliation Network Projected impact for the 2017-2020 (1) IMBECU - CCT CONICET Mendoza, Mendoza, Capacity building: (1) five training courses quadrennium Argentina taught; (2) train Argentinean mammalogists in (2) CEPAVE, La Plata, Argentina By the end of 2020, we envision the Anteater, Sloth Red List assessments. and Armadillo Specialist Group (ASASG) will have Proposal development and funding: secure Number of members achieved increased protection for our priority funding to replenish the Xenarthra Conserva- 25 species, the Critically Endangered Pygmy Three- tion Fund. toed Sloth (Bradypus pygmaeus) and the Vulner- Synergy: enter into partnership with zoological able Brazilian Three-banded Armadillo (Tolypeutes Social networks institutions. tricinctus). We aim to reach this goal by increasing Facebook: Communicate IUCN/SSC Anteater, Sloth and Armadillo Special- scientific knowledge, raising awareness, devel- Communication: (1) four issues of the ASASG ist Group oping and implementing comprehensive action Newsletter published; (2) increase awareness. Website: plans and securing protection of their habitat. www.xenarthrans.org Capacity building through training courses will allow us to increase the number of researchers Activities and results 2018 dedicated to conservation-relevant research on Assess armadillos, sloths and anteaters.
    [Show full text]
  • Sociedad Argentina Para El Estudio De Los Mamíferos Versión On-Line ISSN 2618-4788
    Sociedad Argentina para el Estudio de los Mamíferos Versión on-line ISSN 2618-4788 http://doi.org/10.31687/saremNMS.19.0.07 Patterns of mineral lick visitation by Linnaeus’s two-toed sloth Choloepus didactylus (Pilosa, Megalonychidae) in eastern Ecuador Diego Mosquera (1), Gabriela Vinueza-Hidalgo (1) and John G. Blake (2) (1)Estación de Biodiversidad Tiputini, Colegio de Ciencias Biológicas y Ambientales, Universidad San Francisco de Quito, Quito, Ecuador. (2)Department of Wildlife Ecology and Conservation, University of Florida, Gainesville, Florida, USA. [correspondence: [email protected]] ABSTRACT Geophagy involves the consumption of soil to supplement diets and to facilitate digestive processes. We used camera traps to document the use of a salt lick by Linnaeus’s two-toed sloth Choloepus didactylus (Linnaeus, 1758) from December 2014 to November 2015 in a lowland Ecuadorian forest. We obtained 201 videos of sloths and analyzed if rain or lunar-phase infl uenced these visits. Visits were positively correlated with monthly rainfall and negatively correlated with lunar illumination, but correlations were not signifi cant. We consider three hypotheses for visiting licks: (a) to supplement their diet, (b) to help digestion, and (c ) to obtain water. RESUMEN La geofagia involucra consumo de tierra para complementar la dieta y facilitar procesos digestivos. Utilizamos cámaras para documentar el uso de un saladero por perezosos de dos dedos de Linnaeus Choloepus didactylus (Linnaeus, 1758), desde diciembre 2014 a noviembre 2015, en un bosque de tierras bajas ecuatoriano. Obtuvimos 201 videos y analizamos si la lluvia o la fase lunar infl uyeron en estas visitas. Estas se correlacionaron positivamente con precipitación mensual y negativamente con iluminación lunar, pero las correlaciones no fueron signifi cativas.
    [Show full text]
  • Hematological and Biochemical Profile of Captive Brown-Throated Sloths Bradypus Variegatus, Schinz 1825, Feeding on Ambay Pumpwood Cecropia Pachystachya Trécul 1847
    Arq. Bras. Med. Vet. Zootec., v.73, n.4, p.877-884, 2021 Hematological and biochemical profile of captive brown-throated sloths Bradypus variegatus, Schinz 1825, feeding on ambay pumpwood Cecropia pachystachya Trécul 1847 [Perfil hematológico e bioquímico da preguiça-de-garganta-marrom Bradypus variegatus, Schinz 1825, em cativeiro alimentando-se de embaúba Cecropia pachystachya Trécul 1847] M.C. Tschá1, G.P. Andrade2, P.V. Albuquerque2, A.R. Tschá3, G.S. Dimech3, C.J.F.L. Silva1, E.T.N. Farias3, M.J.A.A.L. Amorim2 1Aluno de pós-graduação – Universidade Federal Rural de Pernambuco ˗ Recife, PE 2Universidade Federal Rural de Pernambuco ˗ Recife, PE 3Centro Universitário - Facol ˗UNIFACOL Vitória de Santo Antão, PE ABSTRACT The aim of this study was to establish reference parameters for the hematological and biochemical levels of five healthy captive sloths of the species Bradypus variegatus (brown-throated sloth) feeding on Cecropia pachystachya (Ambay pumpwood), alternating with a period of free diet in the Dois Irmãos State Park (DISP) Recife, Pernambuco – Brazil. Keywords: tests, hematology, biochemistry, ambay pumpwood, sloths RESUMO O objetivo da presente pesquisa foi estabelecer parâmetros de referência para níveis hematológicos e bioquímicos, de cinco preguiças sadias, da espécie Bradypus variegatus (preguiça-de-garganta-marrom), em cativeiro, alimentando-se de Cecropia pachystachya (embaúba) em períodos alternados com dieta livre, no Parque Estadual de Dois Irmãos (PEDI) Recife, Pernambuco-Brasil. Palavras-chave: exames, hematologia, bioquímica, embaúba, bicho-preguiça INTRODUCTION (International Union for Conservation of Nature) as being of low concern (LC). This species has Sloths, like anteaters, belong to the order Pilosa an ample distribution in the Neotropical region, (Rezende et al., 2013).
    [Show full text]