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David A Taggart - One of the best experts on this subject based on the ideXlab platform.
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activity patterns of the southern hairy nosed wombat lasiorhinus latifrons marsupialia Vombatidae in the south australian murraylands
Australian Mammalogy, 2010Co-Authors: G R Finlayson, G A Shimmin, Ron Dibben, Craig R White, David A TaggartAbstract:The southern hairy-nosed wombat (Lasiorhinus latifrons) is a large, semifossorial, herbivorous marsupial, adapted to a harsh and unpredictable environment in semi-arid Australia. Limited information is available on the biology and general behaviour of the species. The present study examines monthly variability in ‘nocturnal’ activity patterns. Data-loggers were used to investigate the effect of climate on 57 months of activity patterns of 18 wombats between 1999 and 2004. The average period of activity across the study was 6.27 ± 0.24 h in duration across the study. Multiple excursions above ground were more common in September and significantly correlated with both available water and median temperature. Periods of activity were strongly correlated with temperature across the entire study.
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growth and development of the southern hairy nosed wombat lasiorhinus latifrons Vombatidae
Australian Journal of Zoology, 2007Co-Authors: David A Taggart, Vernon R Steele, G R Finlayson, G A Shimmin, Clare Gover, Ron Dibben, Craig R White, Peter TemplesmithAbstract:There are few published studies on breeding and reproduction in hairy-nosed wombats and little information available on growth and development of pouch young. At a field site near Swan Reach in the Murraylands of South Australia morphometric measurements of 353 young southern hairy-nosed wombats and notes on their development were recorded. These data were combined with growth data collected from repeat measures of 10 mother-reared and 5 hand-reared joeys in order to establish information for aging young of this species and to plot developmental changes. Young weighed ~0.4 g at birth and had a head length (HL) of ~5.2 mm. Head length was the most accurate body parameter from which to assess age. Growth of pouch young was linear between birth and ~Day 310 with head length growing at ~0.4 mm HL per day. After Day 300 growth slowed, represented by a polynomial equation. Eyes were open at 5 months and pouch young started to develop fur at 5–6 months of age. Most young were permanently out of pouch at 9 months of age, and were weaned between 11 and 13 months, when they weighed 6–7 kg. Young remained in the burrow for 1–2 months following pouch exit before venturing above ground at night.
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seasonal changes in the testis accessory glands and ejaculate characteristics of the southern hairy nosed wombat lasiorhinus latifrons marsupialia Vombatidae
Journal of Zoology, 2005Co-Authors: Vernon R Steele, David A Taggart, G A Shimmin, Ron Dibben, Craig R White, J R Ratcliff, J Dibben, Peter TemplesmithAbstract:Most mammals exhibit seasonal variation in the reproductive capacity of one or both sexes. While the female southern hairy-nosed wombat Lasiorhinus latifrons is a known seasonal breeder, the extent of seasonality in the male has not been documented. To examine this, gross body measurements including scrotal diameter and the dimensions of the accessory gland bulge were recorded and male reproductive tracts were examined between 1993 and 2000. Testes, epididymides and accessory glands from all males were dissected free of connective tissue and weighed. In addition, matched semen samples were collected over four time points in 2000 corresponding to the breeding season (September), immediately post-breeding season (November), during the non-breeding season (January), and immediately before the onset of the next breeding season (June) as determined from female reproductive status. Semen was collected by electro-ejaculation and analysed for volume, sperm number and motility characteristics. Ejaculate volume, total ejaculate sperm number, percentage motile sperm, and the sperm motility rating and index were all significantly elevated in September and significantly lower in November and January. This correlated with a significant increase in body weight, peri-cloacal gland width, and the weights of the prostate, Cowper's glands, urethral bulb and crus penis. The data confirm that male reproduction in the southern hairy-nosed wombat, like that of the female, is highly seasonal with a peak in reproductive capacity occurring in August-September and a reduction by November.
Philippa Brewer - One of the best experts on this subject based on the ideXlab platform.
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a new species of miocene wombat marsupialia vombatiformes from riversleigh queensland australia and implications for the evolutionary history of the Vombatidae
Palaeontologia Electronica, 2018Co-Authors: Philippa Brewer, Michael Archer, Suzanne J Hand, Gilbert J PriceAbstract:A new species of wombat, Rhizophascolonus ngangaba sp. nov., is described from Miocene deposits at Riversleigh along with additional specimens of Rhizo-phascolonus crowcrofti, and some maxillary and mandibular fragments attributable to Rhizophascolonus. A phylogenetic analysis indicates that Rhizophascolonus is the next most plesiomorphic wombat after Nimbavombatus boodjamullensis. Morphological characters common to Nimbavombatus and Rhizophascolonus suggest that adaptations to high rates of tooth wear in wombats had their origin in the late Oligocene, presumably in response to climatic cooling and its effects on the vegetation. A period of climatic amelioration in the early Miocene may have led to diversification of wombats and/or to an expansion of their range into rainforest habitats. Although wombats form a significant component of Australia's open-forest and woodland habitats from the early Pliocene to Holocene, they appear to have been rare in all palaeoenvironments prior to this.
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additional specimens of the oldest wombat rhizophascolonus crowcrofti Vombatidae marsupialia from the wipajiri formation south australia an intermediate morphology
Journal of Vertebrate Paleontology, 2008Co-Authors: Philippa Brewer, Michael Archer, Suzanne J HandAbstract:Abstract The oldest described vombatid, Rhizophascolonus crowcrofti, is known from late Oligocene/early Miocene deposits in South Australia. It was described based on a single isolated tooth originally interpreted to be P3. It is also the only described vombatid known to have had tooth roots, all others being hypselodont. This paper describes two additional isolated teeth referable to this taxon from the same deposit and presents a re-interpretation of the type specimen as an M4. Possible function of the extensive, but asymmetrically distributed, molar enamel is discussed. Analysis of the structure and probable function of all three teeth leads to the hypothesis that R. crowcrofti was rhizophagous. (Parts of this abstract were presented at the London Evolutionary Research Network [LERN] 5th annual conference at the Natural History Museum in London on September 14, 2007.)
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new record of warendja wakefieldi Vombatidae marsupialia from wombeyan caves new south wales
Alcheringa, 2007Co-Authors: Philippa BrewerAbstract:Brewer, P., June, 2007. New record of Warendja wakefieldi (Vombatidae; Marsupialia) from Wombeyan Caves, New South Wales. Alcheringa 31, 153‐171. ISSN 0311-5518. The plesiomorphic wombat, Warendja wakefieldi Hope & Wilkinson, 1982, is described from Wombeyan Caves, New South Wales. The specimens are presumed to originate from a single individual and include fragments of the skull, jaw and both humeri. Warendja wakefieldi was previously known only from McEacherns Cave in Victoria and the nearby Comaum Forest Cave in South Australia, so its presence in New South Wales substantially increases its known geographic range. The morphology of the humerus of W. wakefieldi displays evidence of fossorial adaptations.
Vernon R Steele - One of the best experts on this subject based on the ideXlab platform.
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growth and development of the southern hairy nosed wombat lasiorhinus latifrons Vombatidae
Australian Journal of Zoology, 2007Co-Authors: David A Taggart, Vernon R Steele, G R Finlayson, G A Shimmin, Clare Gover, Ron Dibben, Craig R White, Peter TemplesmithAbstract:There are few published studies on breeding and reproduction in hairy-nosed wombats and little information available on growth and development of pouch young. At a field site near Swan Reach in the Murraylands of South Australia morphometric measurements of 353 young southern hairy-nosed wombats and notes on their development were recorded. These data were combined with growth data collected from repeat measures of 10 mother-reared and 5 hand-reared joeys in order to establish information for aging young of this species and to plot developmental changes. Young weighed ~0.4 g at birth and had a head length (HL) of ~5.2 mm. Head length was the most accurate body parameter from which to assess age. Growth of pouch young was linear between birth and ~Day 310 with head length growing at ~0.4 mm HL per day. After Day 300 growth slowed, represented by a polynomial equation. Eyes were open at 5 months and pouch young started to develop fur at 5–6 months of age. Most young were permanently out of pouch at 9 months of age, and were weaned between 11 and 13 months, when they weighed 6–7 kg. Young remained in the burrow for 1–2 months following pouch exit before venturing above ground at night.
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seasonal changes in the testis accessory glands and ejaculate characteristics of the southern hairy nosed wombat lasiorhinus latifrons marsupialia Vombatidae
Journal of Zoology, 2005Co-Authors: Vernon R Steele, David A Taggart, G A Shimmin, Ron Dibben, Craig R White, J R Ratcliff, J Dibben, Peter TemplesmithAbstract:Most mammals exhibit seasonal variation in the reproductive capacity of one or both sexes. While the female southern hairy-nosed wombat Lasiorhinus latifrons is a known seasonal breeder, the extent of seasonality in the male has not been documented. To examine this, gross body measurements including scrotal diameter and the dimensions of the accessory gland bulge were recorded and male reproductive tracts were examined between 1993 and 2000. Testes, epididymides and accessory glands from all males were dissected free of connective tissue and weighed. In addition, matched semen samples were collected over four time points in 2000 corresponding to the breeding season (September), immediately post-breeding season (November), during the non-breeding season (January), and immediately before the onset of the next breeding season (June) as determined from female reproductive status. Semen was collected by electro-ejaculation and analysed for volume, sperm number and motility characteristics. Ejaculate volume, total ejaculate sperm number, percentage motile sperm, and the sperm motility rating and index were all significantly elevated in September and significantly lower in November and January. This correlated with a significant increase in body weight, peri-cloacal gland width, and the weights of the prostate, Cowper's glands, urethral bulb and crus penis. The data confirm that male reproduction in the southern hairy-nosed wombat, like that of the female, is highly seasonal with a peak in reproductive capacity occurring in August-September and a reduction by November.
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the palaeoecology of the Vombatidae did giant wombats burrow
Mammal Review, 2001Co-Authors: Andrew P Woolnough, Vernon R SteeleAbstract:Debate over the origins of burrowing in the Vombatidae has continued since the discovery of the remains of the largest of all wombats, Phascolonus gigas, in the nineteenth century. In this paper, we argue that the largest of the ancestors of extant wombats did not burrow due to physical and physiological limitations of burrows. Further, we suggest that the burrowing characteristics of the extant wombats were derived from an ancestor of similar body size (20–40 kg) that is presently not represented in the fossil record.
Peter Templesmith - One of the best experts on this subject based on the ideXlab platform.
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growth and development of the southern hairy nosed wombat lasiorhinus latifrons Vombatidae
Australian Journal of Zoology, 2007Co-Authors: David A Taggart, Vernon R Steele, G R Finlayson, G A Shimmin, Clare Gover, Ron Dibben, Craig R White, Peter TemplesmithAbstract:There are few published studies on breeding and reproduction in hairy-nosed wombats and little information available on growth and development of pouch young. At a field site near Swan Reach in the Murraylands of South Australia morphometric measurements of 353 young southern hairy-nosed wombats and notes on their development were recorded. These data were combined with growth data collected from repeat measures of 10 mother-reared and 5 hand-reared joeys in order to establish information for aging young of this species and to plot developmental changes. Young weighed ~0.4 g at birth and had a head length (HL) of ~5.2 mm. Head length was the most accurate body parameter from which to assess age. Growth of pouch young was linear between birth and ~Day 310 with head length growing at ~0.4 mm HL per day. After Day 300 growth slowed, represented by a polynomial equation. Eyes were open at 5 months and pouch young started to develop fur at 5–6 months of age. Most young were permanently out of pouch at 9 months of age, and were weaned between 11 and 13 months, when they weighed 6–7 kg. Young remained in the burrow for 1–2 months following pouch exit before venturing above ground at night.
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seasonal changes in the testis accessory glands and ejaculate characteristics of the southern hairy nosed wombat lasiorhinus latifrons marsupialia Vombatidae
Journal of Zoology, 2005Co-Authors: Vernon R Steele, David A Taggart, G A Shimmin, Ron Dibben, Craig R White, J R Ratcliff, J Dibben, Peter TemplesmithAbstract:Most mammals exhibit seasonal variation in the reproductive capacity of one or both sexes. While the female southern hairy-nosed wombat Lasiorhinus latifrons is a known seasonal breeder, the extent of seasonality in the male has not been documented. To examine this, gross body measurements including scrotal diameter and the dimensions of the accessory gland bulge were recorded and male reproductive tracts were examined between 1993 and 2000. Testes, epididymides and accessory glands from all males were dissected free of connective tissue and weighed. In addition, matched semen samples were collected over four time points in 2000 corresponding to the breeding season (September), immediately post-breeding season (November), during the non-breeding season (January), and immediately before the onset of the next breeding season (June) as determined from female reproductive status. Semen was collected by electro-ejaculation and analysed for volume, sperm number and motility characteristics. Ejaculate volume, total ejaculate sperm number, percentage motile sperm, and the sperm motility rating and index were all significantly elevated in September and significantly lower in November and January. This correlated with a significant increase in body weight, peri-cloacal gland width, and the weights of the prostate, Cowper's glands, urethral bulb and crus penis. The data confirm that male reproduction in the southern hairy-nosed wombat, like that of the female, is highly seasonal with a peak in reproductive capacity occurring in August-September and a reduction by November.
Craig R White - One of the best experts on this subject based on the ideXlab platform.
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activity patterns of the southern hairy nosed wombat lasiorhinus latifrons marsupialia Vombatidae in the south australian murraylands
Australian Mammalogy, 2010Co-Authors: G R Finlayson, G A Shimmin, Ron Dibben, Craig R White, David A TaggartAbstract:The southern hairy-nosed wombat (Lasiorhinus latifrons) is a large, semifossorial, herbivorous marsupial, adapted to a harsh and unpredictable environment in semi-arid Australia. Limited information is available on the biology and general behaviour of the species. The present study examines monthly variability in ‘nocturnal’ activity patterns. Data-loggers were used to investigate the effect of climate on 57 months of activity patterns of 18 wombats between 1999 and 2004. The average period of activity across the study was 6.27 ± 0.24 h in duration across the study. Multiple excursions above ground were more common in September and significantly correlated with both available water and median temperature. Periods of activity were strongly correlated with temperature across the entire study.
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growth and development of the southern hairy nosed wombat lasiorhinus latifrons Vombatidae
Australian Journal of Zoology, 2007Co-Authors: David A Taggart, Vernon R Steele, G R Finlayson, G A Shimmin, Clare Gover, Ron Dibben, Craig R White, Peter TemplesmithAbstract:There are few published studies on breeding and reproduction in hairy-nosed wombats and little information available on growth and development of pouch young. At a field site near Swan Reach in the Murraylands of South Australia morphometric measurements of 353 young southern hairy-nosed wombats and notes on their development were recorded. These data were combined with growth data collected from repeat measures of 10 mother-reared and 5 hand-reared joeys in order to establish information for aging young of this species and to plot developmental changes. Young weighed ~0.4 g at birth and had a head length (HL) of ~5.2 mm. Head length was the most accurate body parameter from which to assess age. Growth of pouch young was linear between birth and ~Day 310 with head length growing at ~0.4 mm HL per day. After Day 300 growth slowed, represented by a polynomial equation. Eyes were open at 5 months and pouch young started to develop fur at 5–6 months of age. Most young were permanently out of pouch at 9 months of age, and were weaned between 11 and 13 months, when they weighed 6–7 kg. Young remained in the burrow for 1–2 months following pouch exit before venturing above ground at night.
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seasonal changes in the testis accessory glands and ejaculate characteristics of the southern hairy nosed wombat lasiorhinus latifrons marsupialia Vombatidae
Journal of Zoology, 2005Co-Authors: Vernon R Steele, David A Taggart, G A Shimmin, Ron Dibben, Craig R White, J R Ratcliff, J Dibben, Peter TemplesmithAbstract:Most mammals exhibit seasonal variation in the reproductive capacity of one or both sexes. While the female southern hairy-nosed wombat Lasiorhinus latifrons is a known seasonal breeder, the extent of seasonality in the male has not been documented. To examine this, gross body measurements including scrotal diameter and the dimensions of the accessory gland bulge were recorded and male reproductive tracts were examined between 1993 and 2000. Testes, epididymides and accessory glands from all males were dissected free of connective tissue and weighed. In addition, matched semen samples were collected over four time points in 2000 corresponding to the breeding season (September), immediately post-breeding season (November), during the non-breeding season (January), and immediately before the onset of the next breeding season (June) as determined from female reproductive status. Semen was collected by electro-ejaculation and analysed for volume, sperm number and motility characteristics. Ejaculate volume, total ejaculate sperm number, percentage motile sperm, and the sperm motility rating and index were all significantly elevated in September and significantly lower in November and January. This correlated with a significant increase in body weight, peri-cloacal gland width, and the weights of the prostate, Cowper's glands, urethral bulb and crus penis. The data confirm that male reproduction in the southern hairy-nosed wombat, like that of the female, is highly seasonal with a peak in reproductive capacity occurring in August-September and a reduction by November.
