Browsing by Subject "Strepsirhini"

Now showing 1 - 7 of 7
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    A comparison of activity patterns for captive Propithecus tattersalli and Propithecus coquereli.
    (Zoo Biol, 2016-03) Wallace, Gregory L; Paquette, Lisa B; Glander, Kenneth E
    The activity patterns and social interactions of two species of captive sifaka were observed during a 2-year period. Allogrooming was not observed in golden-crowned sifaka and they spent significantly more time resting than the Coquerel's sifaka. Females of both species were found to be dominant to males. The golden-crowned sifaka (Propithecus tattersalli) spent significantly less time feeding than the Coquerel's sifaka. Temperature, time of day, species, and interpair comparisons for the golden-crowned sifaka were found to affect activity and social interactions, while gender did not. Like the Coquerel's sifaka, the golden-crowned sifaka was found to be diurnal; however, they differed in that the golden-crowned sifaka did not descend to the ground.
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    A digital collection of rare and endangered lemurs and other primates from the Duke Lemur Center.
    (PloS one, 2019-01) Yapuncich, Gabriel S; Kemp, Addison D; Griffith, Darbi M; Gladman, Justin T; Ehmke, Erin; Boyer, Doug M
    Scientific study of lemurs, a group of primates found only on Madagascar, is crucial for understanding primate evolution. Unfortunately, lemurs are among the most endangered animals in the world, so there is a strong impetus to maximize as much scientific data as possible from available physical specimens. MicroCT scanning efforts at Duke University have resulted in scans of more than 100 strepsirrhine cadavers representing 18 species from the Duke Lemur Center. An error study of the microCT scanner recovered less than 0.3% error at multiple resolution levels. Scans include specimen overviews and focused, high-resolution selections of complex anatomical regions (e.g., cranium, hands, feet). Scans have been uploaded to MorphoSource, an online digital repository for 3D data. As captive (but free ranging) individuals, these specimens have a wealth of associated information that is largely unavailable for wild populations, including detailed life history data. This digital collection maximizes the information obtained from rare and endangered animals with minimal degradation of the original specimens.
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    Darwinius masillae is a strepsirrhine--a reply to Franzen et al. (2009).
    (Journal of human evolution, 2010-11) Williams, Blythe A; Kay, Richard F; Kirk, E Christopher; Ross, Callum F
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    Hand and foot pressures in the aye-aye (Daubentonia madagascariensis) reveal novel biomechanical trade-offs required for walking on gracile digits.
    (J Exp Biol, 2010-05) Kivell, Tracy L; Schmitt, Daniel; Wunderlich, Roshna E
    Arboreal animals with prehensile hands must balance the complex demands of bone strength, grasping and manipulation. An informative example of this problem is that of the aye-aye (Daubentonia madagascariensis), a rare lemuriform primate that is unusual in having exceptionally long, gracile fingers specialized for foraging. In addition, they are among the largest primates to engage in head-first descent on arboreal supports, a posture that should increase loads on their gracile digits. We test the hypothesis that aye-ayes will reduce pressure on their digits during locomotion by curling their fingers off the substrate. This hypothesis was tested using simultaneous videographic and pressure analysis of the hand, foot and digits for five adult aye-ayes during horizontal locomotion and during ascent and descent on a 30 degrees instrumented runway. Aye-ayes consistently curled their fingers during locomotion on all slopes. When the digits were in contact with the substrate, pressures were negligible and significantly less than those experienced by the palm or pedal digits. In addition, aye-ayes lifted their hands vertically off the substrate instead of 'toeing-off' and descended head-first at significantly slower speeds than on other slopes. Pressure on the hand increased during head-first descent relative to horizontal locomotion but not as much as the pressure increased on the foot during ascent. This distribution of pressure suggests that aye-ayes shift their weight posteriorly during head-first descent to reduce loads on their gracile fingers. This research demonstrates several novel biomechanical trade-offs to deal with complex functional demands on the mammalian skeleton.
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    Intake, digestibility, and passage of a commercially designed diet by two Propithecus species.
    (Am J Primatol, 1999) Campbell, JL; Eisemann, JH; Glander, KE; Crissey, SD
    The digestibility and passage of an experimental diet was used to compare the digestive physiology of two Propithecus species: P. verreauxi and P. tattersalli. Though both animals have a similar feeding ecology, the captive status of P. verreauxi is considered more stable than that of P. tattersalli. The test diet included a local tree species, Rhus copallina, at 15% of dry matter intake (DMI) and Mazuri Leafeater Primate Diet at 85% of DMI. The chemical composition of the diet (dry matter basis) was 25% crude protein, 34% neutral detergent fiber (NDF), and 22% acid detergent fiber (ADF) with a gross energy of 4.52 kcal/g. After a 6 week acclimation to the experimental diet, animals were placed in research caging. After a 7 day adjustment period, animals were dosed with chromium mordant and Co-EDTA as markers for digesta passage and all feed refusals and feces were collected at timed intervals for 7 days. Digestibility values, similar for both species, were approximately 65% for dry matter, crude protein, and energy, and 40% and 35% respectively, for NDF and ADF. Transit times (17-18.5 hr) and mean retention times (31-34 hr) were not significantly different between species, and there was no difference between the chromium mordant and Co-EDTA. Serum values for glucose, urea, and non-esterified fatty acids (NEFA) were obtained during four different time periods to monitor nutritional status. While there was no change in serum glucose, serum urea increased over time. The NEFAs increased across all four time periods for P. verreauxi and increased for the first three periods then decreased in the last period for P. tattersalli. Results obtained indicate no difference in digestibility nor digesta passage between species, and that both Propithecus species were similar to other post-gastric folivores.
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    Interspecies Papillomavirus Type Infection and a Novel Papillomavirus Type in Red Ruffed Lemurs (Varecia rubra).
    (Viruses, 2023-12) Paietta, Elise N; Kraberger, Simona; Regney, Melanie; Custer, Joy M; Ehmke, Erin; Yoder, Anne D; Varsani, Arvind
    The Papillomaviridae are a family of vertebrate-infecting viruses of oncogenic potential generally thought to be host species- and tissue-specific. Despite their phylogenetic relatedness to humans, there is a scarcity of data on papillomaviruses (PVs) in speciose non-human primate lineages, particularly the lemuriform primates. Varecia variegata (black-and-white ruffed lemurs) and Varecia rubra (red ruffed lemurs), two closely related species comprising the Varecia genus, are critically endangered with large global captive populations. Varecia variegata papillomavirus (VavPV) types -1 and -2, the first PVs in lemurs with a fully identified genome, were previously characterized from captive V. variegata saliva. To build upon this discovery, saliva samples were collected from captive V. rubra with the following aims: (1) to identify PVs shared between V. variegata and V. rubra and (2) to characterize novel PVs in V. rubra to better understand PV diversity in the lemuriform primates. Three complete PV genomes were determined from V. rubra samples. Two of these PV genomes share 98% L1 nucleotide identity with VavPV2, denoting interspecies infection of V. rubra by VavPV2. This work represents the first reported case of interspecies PV infection amongst the strepsirrhine primates. The third PV genome shares <68% L1 nucleotide identity with that of all PVs. Thus, it represents a new PV species and has been named Varecia rubra papillomavirus 1 (VarPV1). VavPV1, VavPV2, and VarPV1 form a new clade within the Papillomaviridae family, likely representing a novel genus. Future work diversifying sample collection (i.e., lemur host species from multiple genera, sample type, geographic location, and wild populations) is likely to uncover a world of diverse lemur PVs.
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    Relative growth of the limbs and trunk in sifakas: heterochronic, ecological, and functional considerations.
    (Am J Phys Anthropol, 1993-12) Ravosa, MJ; Meyers, DM; Glander, KE
    Limb, trunk, and body weight measurements were obtained for growth series of Milne-Edwards's diademed sifaka, Propithecus diadema edwardsi, and the golden-crowned sifaka, Propithecus tattersalli. Similar measures were obtained also for primarily adults of two subspecies of the western sifaka: Propithecus verreauxi coquereli, Coquerel's sifaka, and Propithecus verreauxi verreauxi, Verreaux's sifaka. Ontogenetic series for the larger-bodied P. d. edwardsi and the smaller-bodied P. tattersalli were compared to evaluate whether species-level differences in body proportions result from the differential extension of common patterns of relative growth. In bivariate plots, both subspecies of P. verreauxi were included to examine whether these taxa also lie along a growth trajectory common to all sifakas. Analyses of the data indicate that postcranial proportions for sifakas are ontogenetically scaled, much as demonstrated previously with cranial dimensions for all three species (Ravosa, 1992). As such, P. d. edwardsi apparently develops larger overall size primarily by growing at a faster rate, but not for a longer duration of time, than P. tattersalli and P. verreauxi; this is similar to results based on cranial data. A consideration of Malagasy lemur ecology suggests that regional differences in forage quality and resource availability have strongly influenced the evolutionary development of body-size variation in sifakas. On one hand, the rainforest environment of P. d. edwardsi imposes greater selective pressures for larger body size than the dry-forest environment of P. tattersalli and P. v. coquereli, or the semi-arid climate of P. v. verreauxi. On the other hand, as progressively smaller-bodied adult sifakas are located in the east, west, and northwest, this apparently supports suggestions that adult body size is set by dry-season constraints on food quality and distribution (i.e., smaller taxa are located in more seasonal habitats such as the west and northeast). Moreover, the fact that body-size differentiation occurs primarily via differences in growth rate is also due apparently to differences in resource seasonality (and juvenile mortality risk in turn) between the eastern rainforest and the more temperate northeast and west. Most scaling coefficients for both arm and leg growth range from slight negative allometry to slight positive allometry. Given the low intermembral index for sifakas, which is also an adaptation for propulsive hindlimb-dominated jumping, this suggests that differences in adult limb proportions are largely set prenatally rather than being achieved via higher rates of postnatal hindlimb growth.(ABSTRACT TRUNCATED AT 400 WORDS)