Loxodonta

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Anne Savage - One of the best experts on this subject based on the ideXlab platform.

  • accelerometers in collars identify behavioral states in captive african elephants Loxodonta africana
    Endangered Species Research, 2012
    Co-Authors: Joseph Soltis, Rory P Wilson, Iain Douglashamilton, Lucy E King, Fritz Vollrath, Anne Savage
    Abstract:

    Accelerometers are motion-detection devices that, when attached to animals, are capable of detecting body orientation, overall activity levels, and specific behavior patterns. We deployed accelerometers in order to study the hypothesis that accelerometer output would allow us to distinguish between 4 behavior patterns in 3 adult female African elephants Loxodonta africana at Disney's Animal Kingdom®, Florida, USA. Tri-axial accelerometer data loggers were attached to the tops of collars worn around the elephants' necks. Behavior was documented on video while the accelerometer output was stored on the data logger. Feeding, bathing, and walk- ing behaviors were recorded in all 3 subjects, while swaying behavior could be recorded in only 1 subject. Data in the 3 physical dimensions (sway, surge, and heave) were analyzed in terms of overall magnitude of movement (dynamic acceleration) and in terms of the periodicity of move- ment. When classifying accelerometer data of unlabeled origin to the correct behavioral state, overall success ranged from 70 to 91%. Bathing was sometimes confused with feeding and walk- ing, but feeding, walking, and swaying were easily distinguished from each other. These results show that data from accelerometers can distinguish an elephant's behavioral states, and thus may be used to monitor elephant behavior remotely. Such devices could be deployed for a variety of purposes, ranging from monitoring elephant activity in zoos to an early-warning system that could alert the authorities when wild elephants are being illegally hunted.

  • the expression of affect in african elephant Loxodonta africana rumble vocalizations
    Journal of Comparative Psychology, 2009
    Co-Authors: Joseph Soltis, Katherine A Leighty, Christina M Wesolek, Anne Savage
    Abstract:

    : Affective states are thought to be expressed in the mammalian voice, but such investigations are most common in primates. Source and filter features of rumbles were analyzed from 6 adult female African elephants (Loxodonta africana) at Disney's Animal Kingdom. Rumbles produced during periods of minimal social interaction ("low affect") were compared to those produced during dominance interactions ("high affect"). Low-ranking females produced rumbles with increased and more variable fundamental frequencies, and increased durations and amplitudes during dominance interactions with superiors, compared to the low affect context. This acoustic response is consistent with the expression of affect in mammals and may signal submission to superiors. The 2 highest ranking females were codominant and competed for alpha status. They produced rumbles with decreased and less variable fundamental frequencies, increased durations and amplitudes, and a decrease in formant dispersion during dominance interactions with each other, compared to the low affect context. This response is not generally consistent with the expression of affect, but may signal large body size to competitors. These results suggest that affect can be expressed in the voiced sounds of elephants.

  • gps determination of walking rates in captive african elephants Loxodonta africana
    Zoo Biology, 2009
    Co-Authors: Katherine A Leighty, Christina M Wesolek, Jill Mellen, Joseph Soltis, Anne Savage, John Lehnhardt
    Abstract:

    The movements of elephants in captivity have been an issue of concern for animal welfare activists and zoological professionals alike in recent years. In order to fully understand how movement rates reflect animal welfare, we must first determine the exact distances these animals move in the captive environment. We outfitted seven adult female African elephants (Loxodonta africana) at Disney's Animal Kingdom with collar-mounted global positioning recording systems to document their movement rates while housed in outdoor guest viewing habitats. Further, we conducted preliminary analyses to address potential factors impacting movement rates including body size, temperature, enclosure size, and social grouping complexity. We found that our elephants moved at an average rate of 0.409±0.007 km/hr during the 9-hr data collection periods. This rate translates to an average of 3.68 km traveled during the observation periods, at a rate comparable to that observed in the wild. Although movement rate did not have a significant relationship with an individual's body size in this herd, the movements of four females demonstrated a significant positive correlation with temperature. Further, females in our largest social group demonstrated a significant increase in movement rates when residing in larger enclosures. We also present preliminary evidence suggesting that increased social group complexity, including the presence of infants in the herd, may be associated with increased walking rates, whereas factors such as reproductive and social status may constrain movements. Zoo Biol 28:16–28, 2009. © 2008 Wiley-Liss, Inc.

  • gps determination of walking rates in captive african elephants Loxodonta africana
    Zoo Biology, 2009
    Co-Authors: Katherine A Leighty, Christina M Wesolek, Jill Mellen, Joseph Soltis, Anne Savage, John Lehnhardt
    Abstract:

    The movements of elephants in captivity have been an issue of concern for animal welfare activists and zoological professionals alike in recent years. In order to fully understand how movement rates reflect animal welfare, we must first determine the exact distances these animals move in the captive environment. We outfitted seven adult female African elephants (Loxodonta africana) at Disney's Animal Kingdom with collar-mounted global positioning recording systems to document their movement rates while housed in outdoor guest viewing habitats. Further, we conducted preliminary analyses to address potential factors impacting movement rates including body size, temperature, enclosure size, and social grouping complexity. We found that our elephants moved at an average rate of 0.409+/-0.007 km/hr during the 9-hr data collection periods. This rate translates to an average of 3.68 km traveled during the observation periods, at a rate comparable to that observed in the wild. Although movement rate did not have a significant relationship with an individual's body size in this herd, the movements of four females demonstrated a significant positive correlation with temperature. Further, females in our largest social group demonstrated a significant increase in movement rates when residing in larger enclosures. We also present preliminary evidence suggesting that increased social group complexity, including the presence of infants in the herd, may be associated with increased walking rates, whereas factors such as reproductive and social status may constrain movements.

  • rumble vocalizations mediate interpartner distance in african elephants Loxodonta africana
    Animal Behaviour, 2008
    Co-Authors: Katherine A Leighty, Christina M Wesolek, Joseph Soltis, Anne Savage
    Abstract:

    The ability to utilize contact calls to facilitate reunions with social partners has been documented in a number of species showing a fission/fusion social organization. Field observations and playback experiments suggest that African elephants use low-frequency rumble vocalizations to reunite with their herd members following periods of fission. Using a digital audio and GPS recording collar system, we documented the production of rumbles and subsequent movements of five adult female African elephants at Disney's Animal Kingdom, Bay Lake, Florida, U.S.A. This recording system allowed us to identify the producer of each rumble and to document the effect of rumbles on the movements of herd members relative to the caller. Our findings provide the first empirical evidence that spontaneously produced elephant rumble vocalizations function in part to mediate the spatial relationships of group members. Overall, the production of rumbles resulted in a net decrease in distance between the caller and her social partners. This approach behaviour was enhanced if the partner was highly affiliated with the caller, if the partner replied with a rumble of her own, and if the pair was initially far apart (≥61 m). Rumble production was likely to result in avoidance behaviour only when there was no rumble reply by the partner and the dyad was close together prior to the initial call. These results suggest that a general function of elephant rumbles is to promote spatial cohesion among separated group members, but they may also mediate a variety of other close-distance social interactions.

Makoto Kato - One of the best experts on this subject based on the ideXlab platform.

Joseph Soltis - One of the best experts on this subject based on the ideXlab platform.

  • accelerometers in collars identify behavioral states in captive african elephants Loxodonta africana
    Endangered Species Research, 2012
    Co-Authors: Joseph Soltis, Rory P Wilson, Iain Douglashamilton, Lucy E King, Fritz Vollrath, Anne Savage
    Abstract:

    Accelerometers are motion-detection devices that, when attached to animals, are capable of detecting body orientation, overall activity levels, and specific behavior patterns. We deployed accelerometers in order to study the hypothesis that accelerometer output would allow us to distinguish between 4 behavior patterns in 3 adult female African elephants Loxodonta africana at Disney's Animal Kingdom®, Florida, USA. Tri-axial accelerometer data loggers were attached to the tops of collars worn around the elephants' necks. Behavior was documented on video while the accelerometer output was stored on the data logger. Feeding, bathing, and walk- ing behaviors were recorded in all 3 subjects, while swaying behavior could be recorded in only 1 subject. Data in the 3 physical dimensions (sway, surge, and heave) were analyzed in terms of overall magnitude of movement (dynamic acceleration) and in terms of the periodicity of move- ment. When classifying accelerometer data of unlabeled origin to the correct behavioral state, overall success ranged from 70 to 91%. Bathing was sometimes confused with feeding and walk- ing, but feeding, walking, and swaying were easily distinguished from each other. These results show that data from accelerometers can distinguish an elephant's behavioral states, and thus may be used to monitor elephant behavior remotely. Such devices could be deployed for a variety of purposes, ranging from monitoring elephant activity in zoos to an early-warning system that could alert the authorities when wild elephants are being illegally hunted.

  • Vocal communication in African Elephants (Loxodonta africana)
    Zoo biology, 2010
    Co-Authors: Joseph Soltis
    Abstract:

    Research on vocal communication in African elephants has increased in recent years, both in the wild and in captivity, providing an opportunity to present a comprehensive review of research related to their vocal behavior. Current data indicate that the vocal repertoire consists of perhaps nine acoustically distinct call types, "rumbles" being the most common and acoustically variable. Large vocal production anatomy is responsible for the low-frequency nature of rumbles, with fundamental frequencies in the infrasonic range. Additionally, resonant frequencies of rumbles implicate the trunk in addition to the oral cavity in shaping the acoustic structure of rumbles. Long-distance communication is thought possible because low-frequency sounds propagate more faithfully than high-frequency sounds, and elephants respond to rumbles at distances of up to 2.5 km. Elephant ear anatomy appears designed for detecting low frequencies, and experiments demonstrate that elephants can detect infrasonic tones and discriminate small frequency differences. Two vocal communication functions in the African elephant now have reasonable empirical support. First, closely bonded but spatially separated females engage in rumble exchanges, or "contact calls," that function to coordinate movement or reunite animals. Second, both males and females produce "mate attraction" rumbles that may advertise reproductive states to the opposite sex. Additionally, there is evidence that the structural variation in rumbles reflects the individual identity, reproductive state, and emotional state of callers. Growth in knowledge about the communication system of the African elephant has occurred from a rich combination of research on wild elephants in national parks and captive elephants in zoological parks.

  • vocal communication in african elephants Loxodonta africana
    Zoo Biology, 2009
    Co-Authors: Joseph Soltis
    Abstract:

    Research on vocal communication in African elephants has increased in recent years, both in the wild and in captivity, providing an opportunity to present a comprehensive review of research related to their vocal behavior. Current data indicate that the vocal repertoire consists of perhaps nine acoustically distinct call types, "rumbles" being the most common and acoustically variable. Large vocal production anatomy is responsible for the low-frequency nature of rumbles, with fundamental frequencies in the infrasonic range. Additionally, resonant frequencies of rumbles implicate the trunk in addition to the oral cavity in shaping the acoustic structure of rumbles. Long-distance communication is thought possible because low-frequency sounds propagate more faithfully than high-frequency sounds, and elephants respond to rumbles at distances of up to 2.5 km. Elephant ear anatomy appears designed for detecting low frequencies, and experiments demonstrate that elephants can detect infrasonic tones and discriminate small frequency differences. Two vocal communication functions in the African elephant now have reasonable empirical support. First, closely bonded but spatially separated females engage in rumble exchanges, or "contact calls," that function to coordinate movement or reunite animals. Second, both males and females produce "mate attraction" rumbles that may advertise reproductive states to the opposite sex. Additionally, there is evidence that the structural variation in rumbles reflects the individual identity, reproductive state, and emotional state of callers. Growth in knowledge about the communication system of the African elephant has occurred from a rich combination of research on wild elephants in national parks and captive elephants in zoological parks.

  • the expression of affect in african elephant Loxodonta africana rumble vocalizations
    Journal of Comparative Psychology, 2009
    Co-Authors: Joseph Soltis, Katherine A Leighty, Christina M Wesolek, Anne Savage
    Abstract:

    : Affective states are thought to be expressed in the mammalian voice, but such investigations are most common in primates. Source and filter features of rumbles were analyzed from 6 adult female African elephants (Loxodonta africana) at Disney's Animal Kingdom. Rumbles produced during periods of minimal social interaction ("low affect") were compared to those produced during dominance interactions ("high affect"). Low-ranking females produced rumbles with increased and more variable fundamental frequencies, and increased durations and amplitudes during dominance interactions with superiors, compared to the low affect context. This acoustic response is consistent with the expression of affect in mammals and may signal submission to superiors. The 2 highest ranking females were codominant and competed for alpha status. They produced rumbles with decreased and less variable fundamental frequencies, increased durations and amplitudes, and a decrease in formant dispersion during dominance interactions with each other, compared to the low affect context. This response is not generally consistent with the expression of affect, but may signal large body size to competitors. These results suggest that affect can be expressed in the voiced sounds of elephants.

  • gps determination of walking rates in captive african elephants Loxodonta africana
    Zoo Biology, 2009
    Co-Authors: Katherine A Leighty, Christina M Wesolek, Jill Mellen, Joseph Soltis, Anne Savage, John Lehnhardt
    Abstract:

    The movements of elephants in captivity have been an issue of concern for animal welfare activists and zoological professionals alike in recent years. In order to fully understand how movement rates reflect animal welfare, we must first determine the exact distances these animals move in the captive environment. We outfitted seven adult female African elephants (Loxodonta africana) at Disney's Animal Kingdom with collar-mounted global positioning recording systems to document their movement rates while housed in outdoor guest viewing habitats. Further, we conducted preliminary analyses to address potential factors impacting movement rates including body size, temperature, enclosure size, and social grouping complexity. We found that our elephants moved at an average rate of 0.409±0.007 km/hr during the 9-hr data collection periods. This rate translates to an average of 3.68 km traveled during the observation periods, at a rate comparable to that observed in the wild. Although movement rate did not have a significant relationship with an individual's body size in this herd, the movements of four females demonstrated a significant positive correlation with temperature. Further, females in our largest social group demonstrated a significant increase in movement rates when residing in larger enclosures. We also present preliminary evidence suggesting that increased social group complexity, including the presence of infants in the herd, may be associated with increased walking rates, whereas factors such as reproductive and social status may constrain movements. Zoo Biol 28:16–28, 2009. © 2008 Wiley-Liss, Inc.

A P Grigorenko - One of the best experts on this subject based on the ideXlab platform.

  • complete mitochondrial genome and phylogeny of pleistocene mammoth mammuthus primigenius
    PLOS Biology, 2006
    Co-Authors: Evgeny I. Rogaev, Yuri K Moliaka, A P Grigorenko, Ilya Chumakov, B A Malyarchuk, M V Derenko, Fyodor A. Kondrashov
    Abstract:

    Phylogenetic relationships between the extinct woolly mammoth(Mammuthus primigenius), and the Asian(Elephas maximus) and African savanna(Loxodonta africana) elephants remain unresolved. Here, we report the sequence of the complete mitochondrial genome (16,842 base pairs) of a woolly mammoth extracted from permafrost-preserved remains from the Pleistocene epoch—the oldest mitochondrial genome sequence determined to date. We demonstrate that well-preserved mitochondrial genome fragments, as long as ~1,600–1700 base pairs, can be retrieved from pre-Holocene remains of an extinct species. Phylogenetic reconstruction of the Elephantinae clade suggests thatM. primigenius andE. maximus are sister species that diverged soon after their common ancestor split from theL. africana lineage. Low nucleotide diversity found between independently determined mitochondrial genomic sequences of woolly mammoths separated geographically and in time suggests that north-eastern Siberia was occupied by a relatively homogeneous population ofM. primigenius throughout the late Pleistocene.

C J Moss - One of the best experts on this subject based on the ideXlab platform.

  • enduring consequences of early experiences 40 year effects on survival and success among african elephants Loxodonta africana
    Biology Letters, 2013
    Co-Authors: Luc F Bussiere, Elizabeth C Webber, Joyce H Poole, C J Moss
    Abstract:

    Growth from conception to reproductive onset in African elephants (Loxodonta africana) provides insights into phenotypic plasticity, individual adaptive plastic responses and facultative maternal investment. Using growth for 867 and life histories for 2652 elephants over 40 years, we demonstrate that maternal inexperience plus drought in early life result in reduced growth rates for sons and higher mortality for both sexes. Slow growth during early lactation was associated with smaller adult size, later age at first reproduction, reduced lifetime survival and consequently limited reproductive output. These enduring effects of trading slow early growth against immediate survival were apparent over the very long term; delayed downstream consequences were unexpected for a species with a maximum longevity of 70þ years and unpredictable environmental experiences.

  • age musth and paternity success in wild male african elephants Loxodonta africana
    Animal Behaviour, 2007
    Co-Authors: Julie A Hollistersmith, Nicholas J Georgiadis, C J Moss, Joyce H Poole, Elizabeth A. Archie, Eric A Vance, Susan C Alberts
    Abstract:

    Male African elephants experience intense intrasexual selection in gaining access to oestrous females, who represent a very scarce and highly mobile resource. An unusual combination of behavioural and physiological traits in males probably reflects this intense selection pressure. Males show prolonged growth, growing throughout much or perhaps all of their long life span (ca. 60e65 years), and they show musth, a physiological and behavioural condition exclusive to elephants, which is manifested by bouts of elevated testosterone and aggression and heightened sexual activity. Most observed matings are by males over 35 years of age and in musth, suggesting that age and musth are both important factors contributing to male reproductive success. Here we report the results of a genetic paternity analysis of a well-studied population of wild African elephants. Patterns of paternity for 119 calves born over a 22-year period showed significant effects of both age and musth on paternity success. Among males in musth, paternity success increased significantly with age until the very oldest age classes, when it modestly declined. When not in musth, males experienced relatively constant, low levels of paternity success at all ages. Thus, despite the importance of both musth and age in determining male paternity success, adult males both in and out of musth, and of all ages, produced calves. In general, however, older males had markedly elevated paternity success compared with younger males, suggesting the possibility of sexual selection for longevity in this species.

  • dominance rank relationships among wild female african elephants Loxodonta africana
    Animal Behaviour, 2006
    Co-Authors: Elizabeth A. Archie, C J Moss, Thomas A Morrison, Charles Foley, Susan C Alberts
    Abstract:

    Socioecological models of the evolution of female-bonded societies predict a relation between resource distribution and the nature of female affiliative and dominance relationships. Species that mainly rely on abundant, widely distributed resources, like African savanna elephants, are predicted to have unresolved dominance hierarchies and poorly differentiated female social relationships. Contrary to this prediction, female elephants have well-differentiated social relationships; however, little is known about the nature of their dominance rank relationships. Here we present the first quantitative analysis of dominance relationships within ‘family’ groups of adult female elephants in two wild populations: one in Amboseli National Park, Kenya, and another in Tarangire National Park, Tanzania. We tested three possibilities, that female elephants: (1) are egalitarian, (2) have linear, nepotistic hierarchies, or (3) have linear age/size-ordered hierarchies. Our results best support the third outcome: dominance rank relationships were transitive within families and highly asymmetrical within dyads, such that older, larger females consistently dominated smaller, younger females. We discuss the implications of this result for understanding the evolution of female social relationships.

  • characterization of tetranucleotide microsatellite loci in the african savannah elephant Loxodonta africana africana
    Molecular Ecology Notes, 2003
    Co-Authors: Elizabeth A. Archie, C J Moss, Susan C Alberts
    Abstract:

    Most African elephant (Loxodonta africana africana) populations are isolated and thus threatened by a loss of genetic diversity. As a consequence, genetic analysis of African elephant populations will play an increasing role in their conservation, and microsatellite loci will be an important tool in these analyses. Previously published sets of polymorphic microsatellites developed for African elephants are all dinucleotide repeats, which are prone to typing error. Here, we characterize 11 tetranucleotide microsatellite loci in the African elephant. All loci were polymorphic in 32 faecal samples and two tissue samples from 33 individual African savannah elephants.

  • the demography of an african elephant Loxodonta africana population in amboseli kenya
    Journal of Zoology, 2001
    Co-Authors: C J Moss
    Abstract:

    This paper presents basic demographic parameters of African elephants (Loxodonta africana) living in and around Amboseli National Park, Kenya. The study was conducted from 1972 to the present and results are based on the histories of 1778 individually known elephants. From 1972 to 1978, the Amboseli elephant population declined and then increased steadily from 1979 to the present. Births occurred throughout the year but over 80% occurred between November and May. Birth rate varied from year to year with a pattern of peaks and troughs at 4- to 5-year intervals. The birth sex ratio did not differ significantly from 1:1. Mean age at first birth was 14.1 years, determined from a sample of 546 known-age females. Mean birth interval (n= 732) was 4.5 years for 255 females. Fecundity and calf survival varied by age of the females. Mortality fluctuated from year to year. Sex-specific mortality rates were consistently higher for males than females at all ages.