DOCSLIB.ORG

Virginia Opossum Didelphis Virginiana

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Virginia Opossum Didelphis Virginiana MAMMALS OF MISSISSIPPI 1:1-8 Virginia Opossum (Didelphis virginiana) BRITTANY L. WILEMON Department of Wildlife and Fisheries, Mississippi State University, Mississippi State, Mississippi, 39762, USA Abstract.—Didelphis virginiana is a small marsupial more commonly known as the opossum. Found primarily in the eastern United States, it is a very hardy mammal that is usually gray with a lighter shade in the north and a darker shade in the south. Known for its opposable tail and its ability to feign death, this primarily nocturnal mammal prefers wooded and moist areas. Didelphis virginiana is a species of little concern, with populations expanding to the north and west. Published 5 December 2008 by the Department of Wildlife and Fisheries, Mississippi State University Virginia opossum spectrum. Weight ranges from 1.9 to 2.8 kg Didelphis virginiana (Kerr, 1792) (McManus 1974). Average life expectancy is approximately 1.5 years. The length of the CONTEXT AND CONTENT tail is relatively large compared to the body Order Didelphimorphia, Family Didelphidae, length. The tail is usually around 90 percent of Subfamily Didelphinae, Genus Didelphis. Four the body length (McManus 1974). The tail is subspecies are recognized. hairless and scale like. The ears are hairless • Subspecies virginiana and are dark gray or black in coloration. The • Subspecies californica adult dental formula (Fig. 2) of the Virginia • Subspecies pigra opossum is i 5/4, c 1/1, p 3/3, m 4/4, 50 total • Subspecies yucatanensis (McManus 1974). • GENERAL CHARACTERS DISTRIBUTION The Virginia opossum ranges in color from The Virginia opossum has been noted as one a light gray in the north to a dark gray in of the most successful mammal species in the southern part of the range. Males are history. This is due to the recent expansion relatively larger than females (McManus of the species northern and western range 1974). Body length ranges from 38 to 51 cm (Weber and O’Conner 2000). The Virginia with males occupying the larger end of the opossum is found in the south and northeastern Fig. 2. Dorsal and lateral view of adult Didelphis Fig. 1. Virginia opossum. Photograph by Karen. virginiana. Average length of skull is 11 cm. Courtesy of www.fl ickr.com Photograph courtesy of Skulls Unlimited. overall appearance (McManus 1974). Sweat glands have proved to be nonfunctional and skin glands are located on the ventral side of males. Female teat numbers can range from ten to seventeen, but thirteen is most common. The Virginia opossum has a relatively small brain case, and the corpus callosum is absent in this species. Vertebral numbers remain fi xed throughout growth and maturation – 7 cervical, 13 thoracic, 6 lumbar, 2 sacral, and 26 to 29 caudal (McManus 1974). The species possesses an opposable hallux on the hind feet. This hallux does not bear a claw, unlike the other digits. Each of the opossum’s feet is covered by ridges used for friction in climbing (McManus 1974). The reproductive system of the male is composed of a scrotum and a hemipenis. The female reproductive system is composed of three vagina, two vagina, which receive the sperm and are laterally placed, and Fig. 3. Geographic distribution of Didelphis virginiana. Photo courtesy of the Smithsonian Book a centrally placed median vagina, which serves of North American Mammals. the purpose of a birth canal (McManus 1974). regions of the United States. The species is Function.—The Virginia opossum has a widely distributed through all of Mississippi. much lower amount of expanded energy due This species is found as far south as Central to thermoregulation than any other placental America and has recently expanded as far mammal (Weber and O’Conner 2000). It north as southern Canada (Kanda 2005). is a homeotherm that can maintain its body The only limitation is the climatic limitation of temperature at ambient temperatures that are temperature. The northern boundary of the lower than zero degrees Celsius (McManus opossums region is limited by the low winter 1969). Many thermoregulatory measures are temperatures (Kanda et al. 2005). It is very taken by the opossum in low temperatures; common for species to experience frostbite or this species has been known to use shivering, mortality due to starvation at the northern edge vasoconstriction, piloerection, and even of their boundaries (Kanda 2005). avoidance of the low temperatures (McManus 1974). Signs of temperature regulation were FORM AND FUNCTION fi rst noted in young at the age of 55 to 60 Form.—The Virginia opossum is a relatively days old, at which the young are still living hardy and stout individual. Males, at 2.8 kg, in the pouch of the female (McManus 1969). are slightly larger than females, which usually At 95 days of age young Virginia opossums reach a weight of about 1.9kg. Species in the were found to be able to hold a deep body north tend to have a denser underfur, which temperature constant at ambient temperatures serves a thermoregulatory function. The as low as fi ve degrees Celsius for a time period underfur tends to be white in the northern of two hours. The average heart rate of a regions and may have dark coloring on the normal Virginia opossum is approximately 200 tips. The species also has guard hairs. beats per minute. After ten days of age, young Opossum populations in the south tend to have develop the means to fi ght infection (McManus a thinner underfur and the guard hairs tend 1974). to be darker. This gives the animal a darker ONTOGENY AND REPRODUCTION particular study to be approximately four miles The mating season of the Virginia opossum per year (Long and Copes 1968). The sex ratio begins in January or February and lasts is slightly preferential to males at 52 percent through June or July in southern states that compared to females at 48 percent. Of the 106 have been studied such as Florida, Georgia, adults examined, 56 were males and 50 were and Texas (McManus 1974). The reproduction females (Llewellyn and Dale 1964). rate of the Virginia opossum was found to be approximately 5.5 (Llewellyn and Dale 1964). Space use.—The Virginia opossum uses a Reproduction yields the highest percentages wide range of habitats. These habitats can be during late January through late March and arid, dry environments, but the species usually May through early June. The estrous cycle prefers wet areas, near a stream or other body averages about 30 days (McManus 1974). of water. It is very diffi cult to estimate home The female is receptive for no longer than range due to the excessive movement of a 36-hour period. Receptiveness ends with opossums. One study provided a home range copulation (McManus 1967). Each of the of approximately 11.5 acres but that is only an two ovaries releases on average 11 ova. estimation. The opossum’s home ranges are Fertilization actually occurs in the fallopian more often a longer course rather than a circle tubes, and the fertilized ovary reaches the shaped course (McManus 1974). One study uterus approximately 24 hours after fertilization. showed that one in every four dens in the range Parturition or birth usually takes place 13 days was occupied by the opossum. The fact that after copulation. Even though the female more dens were always available than were in may posses as many as 13 teats the average use proves that den factors place no limitation litter size is approximately 7 to 9 due to death on the opossum. The preferred dens were of some of the neonates. A female usually usually covered with woody cover or another produces two litters per year with young usually type of protection (Lay 1942). weighing approximately 0.15 grams at the time of birth. The young are considered to be Diet.—The Virginia opossum is omnivorous, altricial at the time of birth (McManus 1974). but the opossums’ diet is mainly composed In the southern distribution range two litter per of insects when they are available. Insects year are most common even though a very low consumed ranged from different species of percentage of females may produce three (Lay crickets to caterpillars. Opossums will also 1942). The further north the opossum lives, consume a wide range of larvae. The diet of the less likely they are to produce two litters the opossum is also comprised of vegetation, per year, but on average the same amount grasses, and fruit. Most of the fruit that is of young are produced in the southern and consumed has fallen from the tree or bush and northern regions (Kanda and Fuller 2004). is readily eaten off of the ground (Hamilton The young remain in the pouch, attached to 1953). The species has also been known the nipple up to 65 days of age. Mortality to consume amphibians, snakes, and birds may occur in the females pouch. The young on occasion. The stomach contents of an are then weaned from the mother at 95 days. opossum population were examined and the Estrus can be resumed after the young or contents proved that the species will consume weaned (McManus 1974). small mammals such as cottontail rabbits, squirrels, and mice. It was also found that the ECOLOGY species will consume other members of the Population characteristics.—Young begin species (Taube 1947). In one particular study, to disperse and forage alone around 90 days the Virginia opossum was found to heavily of age, but they still occasionally return to the rely on earthworms during the winter season mothers den during the day (Gillete 1980). The (Dexter 1951). dispersion rate for this species was noted in a Diseases and Parasites.—Opossums can BEHAVIOR become infected with protozoa’s such as a Grouping behavior.—The Virginia opossum trypanosome.
Load more

Recommended publications
  • Helminths of the Common Opossum Didelphis Marsupialis
    Available online at www.sciencedirect.com Revista Mexicana de Biodiversidad Revista Mexicana de Biodiversidad 88 (2017) 560–571 www.ib.unam.mx/revista/ Taxonomy and systematics Helminths of the common opossum Didelphis marsupialis (Didelphimorphia: Didelphidae), with a checklist of helminths parasitizing marsupials from Peru Helmintos de la zarigüeya común Didelphis marsupialis (Didelphimorphia: Didelphidae), con una lista de los helmintos de marsupiales de Perú a,∗ a b c a Jhon D. Chero , Gloria Sáez , Carlos Mendoza-Vidaurre , José Iannacone , Celso L. Cruces a Laboratorio de Parasitología, Facultad de Ciencias Naturales y Matemática, Universidad Nacional Federico Villarreal, Jr. Río Chepén 290, El Agustino, 15007 Lima, Peru b Universidad Alas Peruanas, Jr. Martínez Copagnon Núm. 1056, 22202 Tarapoto, San Martín, Peru c Laboratorio de Parasitología, Facultad de Ciencias Biológicas, Universidad Ricardo Palma, Santiago de Surco, 15039 Lima, Peru Received 9 June 2016; accepted 27 March 2017 Available online 19 August 2017 Abstract Between May and November 2015, 8 specimens of Didelphis marsupialis Linnaeus, 1758 (Didelphimorphia: Didelphidae) collected in San Martín, Peru were examined for the presence of helminths. A total of 582 helminths representing 11 taxa were identified (2 digeneans and 9 nematodes). Five new host records and 4 species of nematodes [Gongylonemoides marsupialis (Vaz & Pereira, 1934) Freitas & Lent, 1937, Trichuris didelphis Babero, 1960, Viannaia hamata Travassos, 1914 and Viannaia viannaia Travassos, 1914] are added to the composition of the helminth fauna of the marsupials in this country. Further, a checklist of all available published accounts of helminth parasites reported from Peru is provided. To date, a total of 38 helminth parasites have been recorded.
    [Show full text]
  • Monodelphis Domestica in the Opossum Λ Conservation Of
    Marsupial Light Chains: Complexity and Conservation of λ in the Opossum Monodelphis domestica This information is current as Julie E. Lucero, George H. Rosenberg and Robert D. Miller of September 29, 2021. J Immunol 1998; 161:6724-6732; ; http://www.jimmunol.org/content/161/12/6724 Downloaded from References This article cites 35 articles, 10 of which you can access for free at: http://www.jimmunol.org/content/161/12/6724.full#ref-list-1 Why The JI? Submit online. http://www.jimmunol.org/ • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average by guest on September 29, 2021 Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 1998 by The American Association of Immunologists All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. Marsupial Light Chains: Complexity and Conservation of l in the Opossum Monodelphis domestica1,2 Julie E. Lucero, George H. Rosenberg, and Robert D. Miller3 The Igl chains in the South American opossum, Monodelphis domestica, were analyzed at the expressed cDNA and genomic organization level, the first described for a nonplacental mammal.
    [Show full text]
  • OPOSSUM Didelphis Virginiana
    OPOSSUM Didelphis virginiana The Virginia opossum, Didelphis virginiana, is the only marsupial (pouched animal) native to North America. The opossum is not a native species to Vermont, but a population has become established here. The opossum is mostly active at night, being what is referred to as ‘nocturnal.’ They are very good climbers and capable swimmers. These two skills help the opossum avoid predators. It is well known for faking death (also called ‘playing possum’) as another means of outwitting its enemies. The opossum adapts to a wide variety of habitats which has led to its widespread distribution throughout the United States. Vermont Wildlife Fact Sheet Physical Description Opossums breed every other areas near water sources. year, having one litter every They have become very The fur of the Virginia two years. Opossums reach common in urban, suburban, opossum is grayish white in the age of sexual maturity at 6 and farming areas. The color and covers the whole to 7 months. opossum is a wanderer and body except the ears and tail. does not stick to a specific They are about the size of a Food Items territory. The opossum uses large house cat, weighing abandoned burrows, tree between 9 and 13 pounds and The opossum is an cavities, hollow logs, attics, having a body length of 24 to insectivore and an omnivore. garages, or building 40 inches. The opossum has a This means they have a foundations. prehensile tail, one which is varied diet of insects, worms, adapted for grasping and fruits, nuts, and carrion (dead hanging. animals).
    [Show full text]
  • Dominance Relationships in Captive Male Bare-Tailed Woolly Opossum (Caluromys Phiiander, Marsupialia: Didelphidae)
    DOMINANCE RELATIONSHIPS IN CAPTIVE MALE BARE-TAILED WOOLLY OPOSSUM (CALUROMYS PHIIANDER, MARSUPIALIA: DIDELPHIDAE) M.-L. GUILLEMIN*, M. ATRAMENTOWICZ* & P. CHARLES-DOMINIQUE* RÉSUMÉ Au cours de ce travail nous avons voulu tester en captivité l'importance du poids corporel dans l'établissement de relations de dominance chez les mâles Caluromysphilander, chez qui des compétitions inter-mâles ont été étudiées. Les comportements et l'évolution de différents paramètres physiologiques ont été observés durant 18 expérimentations effectuées respectivement sur 6 groupes de deux mâles et sur 12 groupes de deux mâles et une femelle. Des relations de dominance-subordination se mettent en place même en l'absence de femelle, mais la compétition est plus forte dans les groupes comprenant une femelle. Dans ces conditions expérimentales, le rang social est basé principalement sur le poids et l'âge. Lorsque la relation de dominance est mise en place, le rang social des mâles est bien défini et il reste stable jusqu'à la fin de l'expérimentation. Ces relations de dominance stables pourraient profiter aux dominants et aux dominés en minimisant les risques de blessures sérieuses. Les mâles montrent des signes typiques caractérisant un stress social : une baisse du poids et de l'hématocrite, les dominés étant plus stressés que les dominants. Chez les mâles dominants, la baisse de l'hématocrite est plus faible que chez les dominés, et la concentration de testostérone dans le sang diminue plus que chez les dominés. Au niveau comportemental, les dominants effectuent la plupart des interactions agonistiques << offensives » et plus d'investigations olfactives de leur environnement (flairage-léchage) que les dominés.
    [Show full text]
  • Moose Foraging in the Temperate Forests of Southern New England Author(S) :Edward K
    Moose Foraging in the Temperate Forests of Southern New England Author(s) :Edward K. Faison, Glenn Motzkin, David R. Foster and John E. McDonald Source: Northeastern Naturalist, 17(1):1-18. 2010. Published By: Humboldt Field Research Institute DOI: 10.1656/045.017.0101 URL: http://www.bioone.org/doi/full/10.1656/045.017.0101 BioOne (www.bioone.org) is a a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/terms_of_use. Usage of BioOne content is strictly limited to personal, educational, and non- commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder. BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. 2010 NORTHEASTERN NATURALIST 17(1):1–18 Moose Foraging in the Temperate Forests of Southern New England Edward K. Faison1,2,*, Glenn Motzkin1, David R. Foster1, and John E. McDonald3 Abstract - Moose have recently re-colonized the temperate forests of southern New England, raising questions about this herbivore’s effect on forest dynamics in the region. We quantifi ed Moose foraging selectivity and intensity on tree species in rela- tion to habitat features in central Massachusetts.
    [Show full text]
  • Mammals of the Finger Lakes ID Guide
    A Guide for FL WATCH Camera Trappers John Van Niel, Co-PI CCURI and FLCC Professor Nadia Harvieux, Muller Field Station K-12 Outreach Sasha Ewing, FLCC Conservation Department Technician Past and present students at FLCC Virginia Opossum Eastern Coyote Eastern Cottontail Domestic Dog Beaver Red Fox Muskrat Grey Fox Woodchuck Bobcat Eastern Gray Squirrel Feral Cat Red Squirrel American Black Bear Eastern Chipmunk Northern Raccoon Southern Flying Squirrel Striped Skunk Peromyscus sp. North American River Otter North American Porcupine Fisher Brown Rat American Mink Weasel sp. White-tailed Deer eMammal uses the International Union for Conservation of Nature (IUCN) for common and scientific names (with the exception of Domestic Dog) Often the “official” common name of a species is longer than we are used to such as “American Black Bear” or “Northern Raccoon” Please note that it is Grey Fox with an “e” but Eastern Gray Squirrel with an “a”. Face white, body whitish to dark gray. Typically nocturnal. Found in most habitats. About Domestic Cat size. Can climb. Ears and tail tip can show frostbite damage. Very common. Found in variety of habitats. Images are often blurred due to speed. White tail can overexpose in flash. Snowshoe Hare (not shown) is possible in higher elevations. Large, block-faced rodent. Common in aquatic habitats. Note hind feet – large and webbed. Flat tail. When swimming, can be confused with other semi-aquatic mammals. Dark, naked tail. Body brown to blackish (darker when wet). Football-sized rodent. Common in wet habitats. Usually doesn’t stray from water. Pointier face than Beaver.
    [Show full text]
  • Mammals of the Rincon Mountain District, Saguaro National Park
    National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Mammals of the Rincon Mountain District, Saguaro National Park Natural Resource Report NPS/SODN/NRR—2011/437 ON THE COVER Jaguar killed in Rincon Mountains in 1902, photographed at saloon in downtown Tucson. Photograph courtesy Arizona Historical Society. Mammals of the Rincon Mountain District, Saguaro National Park Natural Resource Report NPS/SODN/NRR—2011/437 Author Don E. Swann With contributions by Melanie Bucci, Matthew Caron, Matthew Daniels, Ronnie Sidner, Sandy A. Wolf, and Erin R. Zylstra Saguaro National Park 3693 South Old Spanish Trail Tucson, Arizona 85730-5601 Editing and Design Alice Wondrak Biel Sonoran Desert Network 7660 E. Broadway Blvd., Suite 303 Tucson, AZ 85710 August 2011 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service’s Natural Resource Stewardship and Science offi ce, in Fort Collins, Colo- rado, publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the informa- tion is scientifi cally credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner.
    [Show full text]
  • Late Dry Season Habitat Use of Common Opossum, Didelphis Marsupialis (Marsupialia: Didelphidae) in Neotropical Lower Montane Agricultural Areas
    Rev. Biol. Trop., 47(1-2): 263-269, 1999 www.ucr.ac.cr www.ots.ac.cr www.ots.duke.edu Late dry season habitat use of common opossum, Didelphis marsupialis (Marsupialia: Didelphidae) in neotropical lower montane agricultural areas Christopher S. Vaughan1,2 and L. Foster Hawkins2 1 Regional Wildlife Management Program, Universidad Nacional, Heredia, Costa Rica. Present address: Institute for Environmental Studies, University of Wisconsin, Madison, WI 53705, USA; fax: (608)-262-0014, e-mail: cvaughan- @facstaff.wisc.edu 2 Associated Colleges of the Midwest, San Pedro de M. O., San José, Costa Rica. Received 29-I-1998. Corrected 5-XI-1998. Accepted 13-XI-1998 Abstract: Three Didelphis marsupialis were radio tracked during late dry season (23 February-26 April, 1983) in agricultural area at 1500 m elevation in Central Valley, Costa Rica. All animals were nocturnally active, sig- nificantly more so between 2100-0300 h. Fifty diurnal den site locations were found, 96% inside tree cavities in living fence rows or abandoned squirrel nests in windbreaks. Two females occupied 3.4 and 3.1 ha 95% home ranges, moving an average 890 and 686 m nightly respectively. The male occupied a 5.6 ha 95% home range for 42 days overlapping 90% of females’ home ranges. Over the next 15 days, he moved 1020 m south, establishing three temporary home ranges. During nocturnal movements, windbreaks and living fence rows were used in hig- her proportion than available, while pasture, roads and cultivated lands were used less then available within 100% home ranges. Abandoned coffee and spruce plantations, fruit orchards and overgrown pastures were used in equal proportions to availability in 100% home ranges.
    [Show full text]
  • Marsupial in Maine: Opossum
    Maine Bureau of Parks and Lands www.parksandlands.com Marsupial in Maine: Opossum (Originally published 7/1/2020) If Australia and kangaroos come to mind when you think of marsupials, you are correct. But Maine has one - the Virginia opossum (Didelphis virginianus). Marsupials are mammals that do not give birth to fully developed young. The young are instead born when they are extremely tiny and must then crawl to the mother’s pouch. There, they will suckle milk and continue to grow for many weeks. Baby opossums, called pups or pinkies at birth, are no bigger than a honeybee. Curled up on their side, they are no larger round than a dime and weigh in at approximately .13 grams. This is less than a dime, which weighs 2.268 grams (0.080 ounces)! After a week in their mother’s pouch, their birth weight will have increased by ten times. Opossum are skilled tree climbers. Photo by Kim Chandler. After two months, they are mouse-size and will begin exploring briefly outside the pouch. In another month, they will spend more time outside the pouch and may be carried on their mother’s back. They cling tightly to her fur with their hand-like feet and grasping tails. The night-active (nocturnal) opossum is not a fussy eater. It prefers to stay close to its den but may roam up to two miles nightly in search of food. While ambling along trails near a wetland or stream, it will look for insects, worms, frogs, plants, and seeds to eat. Roads, also visited during the nighttime, are sources of dead animals that the opossum will eat.
    [Show full text]
  • Controlling Raccoon and Opossum Damage
    G1688 Controlling Raccoon and Opossum Damage Stephen Vantassel, Extension Project Coordinator-Wildlife Damage Management Scott Hygnstrom, Extension Specialist-Wildlife Damage Management Dennis Ferraro, Extension Educator—Douglas-Sarpy County Sam Wilson, Furbearer Biologist—Nebraska Game & Parks Commission a shingled roof to establish a den in an attic. Raccoons usu- This NebGuide provides information about rac- ally need only a 4- to 6-inch diameter hole to enter. Smaller coons and opossums, the damage they cause, and ways openings are often enlarged. Raccoons are very strong and to prevent and control damage problems. have tremendous dexterity in their front paws. Despite their size, raccoons are exceptional climbers, able to scale trees, chimneys, and downspouts. Raccoons and opossums are nocturnal, medium-sized Raccoons are omnivores, enjoying a diet ranging from terrestrial mammals that exist throughout Nebraska. They eggs, carrion, food scraps, corn, crayfish, bird seed, worms, can damage lawns and gardens, scatter trash, invade buildings amphibians, pet food and more. While extremely harsh and injure livestock. weather will cause them to remain in their dens, raccoons do not hibernate. Raccoon Facts Opossum Facts Raccoons, with their black bandit Opossums (Didel­ mask and black- and phis virginiana) have brown-banded tail, white to gray coloration are well known to in their fur, grow to Nebraskans (Figure the size of housecats 1). The word “rac- and weigh around 10 coon” is derived from pounds (Figure 3). Their Native American pointed face and rat-like words “arakum” or tail lead many people “aracoun,” meaning to consider them to be Figure 3. Opossum. Figure 1. Raccoon on shingled roof.
    [Show full text]
  • The Biodynamics of Arboreal Locomotion in the Gray Short
    THE BIODYNAMICS OF ARBOREAL LOCOMOTION IN THE GRAY SHORT- TAILED OPOSSUM (MONODELPHIS DOMESTICA) A dissertation presented to the faculty of the College of Arts and Sciences of Ohio University In partial fulfillment of the requirements for the degree Doctor of Philosophy Andrew R. Lammers August 2004 This dissertation entitled THE BIODYNAMICS OF ARBOREAL LOCOMOTION IN THE GRAY SHORT- TAILED OPOSSUM (MONODELPHIS DOMESTICA) BY ANDREW R. LAMMERS has been approved for the Department of Biological Sciences and the College of Arts and Sciences by Audrone R. Biknevicius Associate Professor of Biomedical Sciences Leslie A. Flemming Dean, College of Arts and Sciences LAMMERS, ANDREW R. Ph.D. August 2004. Biological Sciences The biodynamics of arboreal locomotion in the gray short-tailed opossum (Monodelphis domestica). (147 pp.) Director of Dissertation: Audrone R. Biknevicius Most studies of animal locomotor biomechanics examine movement on a level, flat trackway. However, small animals must negotiate heterogenerous terrain that includes changes in orientation and diameter. Furthermore, animals which are specialized for arboreal locomotion may solve the biomechanical problems that are inherent in substrates that are sloped and/or narrow differently from animals which are considered terrestrial. Thus I studied the effects of substrate orientation and diameter on locomotor kinetics and kinematics in the gray short-tailed opossum (Monodelphis domestica). The genus Monodelphis is considered the most terrestrially adapted member of the family Didelphidae, but nevertheless these opossums are reasonably skilled at climbing. The first study (Chapter 2) examines the biomechanics of moving up a 30° incline and down a 30° decline. Substrate reaction forces (SRFs), limb kinematics, and required coefficient of friction were measured.
    [Show full text]
  • AGILE GRACILE OPOSSUM Gracilinanus Agilis (Burmeister, 1854 )
    Smith P - Gracilinanus agilis - FAUNA Paraguay Handbook of the Mammals of Paraguay Number 35 2009 AGILE GRACILE OPOSSUM Gracilinanus agilis (Burmeister, 1854 ) FIGURE 1 - Adult, Brazil (Nilton Caceres undated). TAXONOMY: Class Mammalia; Subclass Theria; Infraclass Metatheria; Magnorder Ameridelphia; Order Didelphimorphia; Family Didelphidae; Subfamily Thylamyinae; Tribe Marmosopsini (Myers et al 2006, Gardner 2007). The genus Gracilinanus was defined by Gardner & Creighton 1989. There are six known species according to the latest revision (Gardner 2007) one of which is present in Paraguay. The generic name Gracilinanus is taken from Latin (gracilis) and Greek (nanos) meaning "slender dwarf", in reference to the slight build of this species. The species name agilis is Latin meaning "agile" referring to the nimble climbing technique of this species. (Braun & Mares 1995). The species is monotypic, but Gardner (2007) considers it to be composite and in need of revision. Furthermore its relationship to the cerrado species Gracilinanus agilis needs to be examined, with some authorities suggesting that the two may be at least in part conspecific - there appear to be no consistent cranial differences (Gardner 2007). Costa et al (2003) found the two species to be morphologically and genetically distinct and the two species have been found in sympatry in at least one locality in Minas Gerais, Brazil (Geise & Astúa 2009) where the authors found that they could be distinguished on external characters alone. Smith P 2009 - AGILE GRACILE OPOSSUM Gracilinanus agilis - Mammals of Paraguay Nº 35 Page 1 Smith P - Gracilinanus agilis - FAUNA Paraguay Handbook of the Mammals of Paraguay Number 35 2009 Patton & Costa (2003) commented that the presence of the similar Gracilinanus microtarsus at Lagoa Santa, Minas Gerais, the type locality for G.agilis , raises the possibility that the type specimen may in fact prove to be what is currently known as G.microtarsus .
    [Show full text]