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Full-Text Articles in Life Sciences

African Elephants Change Gaits When Walking Downhill, Robert H.I. Dale, Robert Warren, Brock Ward, Eric Noble Oct 2011

African Elephants Change Gaits When Walking Downhill, Robert H.I. Dale, Robert Warren, Brock Ward, Eric Noble

Scholarship and Professional Work - LAS

Abstract from the International Elephant and Rhino Conservation and Research Symposium, Rotterdam, NL, October 10-14, 2011.


Birth Statistics For African (Loxodonta Africana) And Asian (Elephas Maximus) Elephants In Human Care: History And Implications For Elephant Welfare, Robert H.I. Dale Mar 2010

Birth Statistics For African (Loxodonta Africana) And Asian (Elephas Maximus) Elephants In Human Care: History And Implications For Elephant Welfare, Robert H.I. Dale

Scholarship and Professional Work - LAS

African (Loxodonta africana) and Asian elephants (Elephas maximus) have lived in the care of humans for many years, yet there is no consensus concerning some basic parameters describing their newborn calves. This study provides a broad empirical basis for generalizations about the birth heights, birth weights, birth times and gestation periods of elephant calves born in captivity. I obtained data concerning at least one of these four characteristics for 218 newborn calves from 74 institutions. Over the past 30 years, newborn Asian elephants have been taller and heavier than newborn African elephants. Neonatal African elephants exhibited sex differences in both ...


A Survey Of The Management And Development Of Captive African Elephant (Loxodonta Africana) Calves: Birth To Three Months Of Age, Nicole L. Kowalski, Robert H.I. Dale, Christa L. H. Mazur Mar 2010

A Survey Of The Management And Development Of Captive African Elephant (Loxodonta Africana) Calves: Birth To Three Months Of Age, Nicole L. Kowalski, Robert H.I. Dale, Christa L. H. Mazur

Scholarship and Professional Work - LAS

We used four surveys to collect information about the birth, physical growth, and behavioral development of 12 African elephant calves born in captivity. The management of the birth process and neonatal care involved a variety of standard procedures. All of the calves were born at night, between 7PM and 7AM. The calves showed a systematic progression in behavioral and physical development, attaining developmental milestones at least a quickly as calves in situ. This study emphasized birth-related events, changes in the ways that calves used their trunks, first instances of behaviors, and interactions of the calves with other, usually adult, elephants ...


Initial Findings On Visual Acuity Thresholds In An African Elephant (Loxodonta Africana), Melissa R. Shyan-Norwalt, Jeff Peterson, Barbara Milankow King, Timothy E. Staggs, Robert H.I. Dale Feb 2010

Initial Findings On Visual Acuity Thresholds In An African Elephant (Loxodonta Africana), Melissa R. Shyan-Norwalt, Jeff Peterson, Barbara Milankow King, Timothy E. Staggs, Robert H.I. Dale

Scholarship and Professional Work - LAS

There are only a few published examinations of elephant visual acuity. All involved Asian elephants (Elephas maximus) and found visual acuity to be between 8′ and 11′ of arc for a stimulus near the tip of the trunk, equivalent to a 0.50 cm gap, at a distance of about 2 m from the eyes. We predicted that African elephants (Loxodonta africana) would have similarly high visual acuity, necessary to facilitate eye-trunk coordination for feeding, drinking and social interactions. When tested on a discrimination task using Landolt-C stimuli, one African elephant cow demonstrated a visual acuity of 48′ of arc ...


The Spatial Memory Of African Elephants (Loxodonta Africana): Durability, Interference, And Response Biases, Robert H.I. Dale May 2008

The Spatial Memory Of African Elephants (Loxodonta Africana): Durability, Interference, And Response Biases, Robert H.I. Dale

Scholarship and Professional Work - LAS

Women and elephants never forget an injury.

-Saki (H. H. Munro), "Reginald on besetting sins," in Reginald (1904)

I am not sure whether the satirist H. H. Munro believed Saki's claim, although it may well be true (at least with regard to elephants). This chapter will examine some characteristics of elephant memory more systematically than did Saki.

In general, it is to an animal's advantage to remember some aspects (usually the stable features) of a situation for long periods and to remember other aspects (usually the unstable features) only temporarily. Consistent with recent arguments questioning the value of ...


Dr. Maximillian Schmidt's 1884 Review Of The Growth Rates Of Asian Elephants, Robert H.I. Dale, Fred Yaniga Jan 2008

Dr. Maximillian Schmidt's 1884 Review Of The Growth Rates Of Asian Elephants, Robert H.I. Dale, Fred Yaniga

Scholarship and Professional Work - LAS

Rarely is there a scientific article of such creativity, insight and importance that it is fascinating even 125 years after it was written. The following article by Max Schmidt, translated in English for the first time, as far as we know, is one of these. As in the original article, an illustration precedes the text.

Dr. Schmidt addressed a topic of considerable interest in recent times (for example, Sukumar, 2003, Appendix 2): The growth curves of elephants. He combined data on multiple elephants from several sources to generate a table of shoulder heights from birth to the age of 34 ...


History: The Birth Of "America" In 1882, Robert H.I. Dale Jan 2008

History: The Birth Of "America" In 1882, Robert H.I. Dale

Scholarship and Professional Work - LAS

This article concerns a New York Times story about the birth of the female Asian elephant calf, named America, at the winter headquarters of the "Greatest Show on Earth" in Bridgeport, Connecticut on February 2, 1882. Phineas T. Barnum, one of the owners of the show, and one prone to self-aggrandizing bluster, claimed that America was the second elephant ever born in captivity. America was born only to months before the arrival in New York of the most famous circus elephant of all time, Jumbo, on Easter Sunday, 1882, and only two years before the origin of a small wagon ...


Tribute: In Memoriam, Jeheskel "Hezy" Shoshani, Robert H.I. Dale Jan 2008

Tribute: In Memoriam, Jeheskel "Hezy" Shoshani, Robert H.I. Dale

Scholarship and Professional Work - LAS

The elephant community has lost one of its great ambassadors, Dr. Jeheskel "Hezy" Shoshani, at the age of 65. A wave of condolences and testimonials from colleagues and friends around the world followed his death on May 21, 2008.


Calf Development: Most Births At Night, Robert H.I. Dale Jan 2008

Calf Development: Most Births At Night, Robert H.I. Dale

Scholarship and Professional Work - LAS

For many years, field researchers studying both African (Loxodonta africana) and Asian (Elephas maximas) elephants have indicated that they have observed relatively few births in situ, suggesting that most elephant dams give birth at night. For example, according to Cynthia Moss, "Possibly the majority of births occur at night and perhaps those that do take place in the daytime happen in secluded places" (1988, p. 151). Others, for example, Clive Spinage, have referred to "the old beliefs that the cows retreated to 'calving grounds' or that birth took place at night." (Spinage, 1994, p. 90). Although observers in several areas ...


The Locomotor Kinematics Of Asian And African Elephants: Changes With Speed And Size, John R. Hutchinson, Delf Schwerda, Daniel J. Famini, Robert H.I. Dale, Martin S. Fischer, Rodger Kram Oct 2006

The Locomotor Kinematics Of Asian And African Elephants: Changes With Speed And Size, John R. Hutchinson, Delf Schwerda, Daniel J. Famini, Robert H.I. Dale, Martin S. Fischer, Rodger Kram

Scholarship and Professional Work - LAS

For centuries, elephant locomotion has been a contentious and confusing challenge for locomotion scientists to understand, not only because of technical difficulties but also because elephant locomotion is in some ways atypical of more familiar quadrupedal gaits. We analyzed the locomotor kinematics of over 2400 strides from 14 African and 48 Asian elephant individuals (body mass 116-4632 kg) freely moving over ground at a 17-fold range of speeds, from slow walking at 0.40 m s-1 to the fastest reliably recorded speed for elephants, 6.8 m s-1. These data reveal that African and Asian elephants have some ...


Hatching Asynchrony, Survival, And The Fitness Of Alternative Adult Morphs In Ambystoma Talpoideum, Travis J. Ryan Jan 2004

Hatching Asynchrony, Survival, And The Fitness Of Alternative Adult Morphs In Ambystoma Talpoideum, Travis J. Ryan

Scholarship and Professional Work - LAS

The mole salamander, Ambystoma talpoideum, exhibits both aquatic (gilled) and terrestrial (metamorphosed) adult morphologies. Previous studies have shown the existence of body-size advantages associated with the terrestrial morph in A. talpoideum and other polymorphic salamanders (e.g., A. tigrinum). However, aquatic adult A. talpoideum mature at a younger age and often breed earlier than terrestrial adults. We tested the hypothesis that early maturation and reproduction in aquatic adults increase fitness (irrespective of body size). We reared larval A. talpoideum in mesocosms and varied the timing of hatching, with early-hatching larvae representing the offspring from early-breeding aquatic adults, and late-hatching larvae ...


Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis J. Ryan, Raymond D. Semlitsch Jan 2003

Growth And The Expression Of Alternative Life Cycles In The Salamander Ambystoma Talpoideum (Caudata: Ambystomatidae), Travis J. Ryan, Raymond D. Semlitsch

Scholarship and Professional Work - LAS

Complex life cycles (CLCs) contain larval and adult phases that are morphologically and ecologically distinct. Simple life cycles (SLCs) have evolved from CLCs repeatedly in a wide variety of lineages but the processes that may underlie the transition have rarely been identified or investigated experimentally. We examined the influence of larval growth rate on the facultative expression of alternative life cycles (metamorphosis or maturation as gill-bearing adults [= paedomorphosis]) in the salamander Ambystoma talpoideum. We manipulated growth rates by altering the amount of food individuals received throughout larval development. The expression of alternative life cycles in A. talpoideum is influenced by ...


Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne Jan 2001

Effects Of Hydroperiod On Metamorphosis In Rana Sphenocephala, Travis J. Ryan, Christopher T. Winne

Scholarship and Professional Work - LAS

Hydroperiod, the time a temporary pond holds water, is an important factor influencing recruitment in amphibian populations and structuring amphibian communities. We conducted an experiment to test the effect of hydroperiod on metamorphic traits of the southern leopard frog (Rana sphenocephala), a common amphibian in the southeastern United States. We reared larval R. sphenocephala in artificial ponds at a density of 32 larvae per tank (initial volume = approximately 650 liter). We dried the tanks according to natural patterns, using three different hydroperiods (60, 75 and 90 d). Experimental hydroperiods had a significant effect on the number of metamorphs and the ...


The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne Jan 2000

The Global Decline Of Reptiles, Deja’ Vu Amphibians, J. Whitfield Gibbons, David E. Scott, Travis J. Ryan, Kurt A. Buhlmann, Tracey D. Tiuberville, Brian S. Metts, Judith L. Greene, Tony Mills, Yale Leiden, Sean Poppy, Christopher T. Winne

Scholarship and Professional Work - LAS

Reptile species are declining on a global scale. Six significant threats to reptile populations are habitat loss and degradation, introduced invasive species, environmental pollution, disease, unsustainable use, and global climate change.


Two Matriarchs Speak, Robert H.I. Dale Sep 1998

Two Matriarchs Speak, Robert H.I. Dale

Scholarship and Professional Work - LAS

Book review for the following titles:

Elephants. By Joyce Poole, Stillwater, MN: Voyageur Press, 1997, 72 pages. $14.95 softcover

Silent Thunder: In the Presence of Elephants. By Katharine Payne, New York: Simon & Schuster, 1998, 286 pages. $25.00 hardcover


The Elephants Of Africa, Robert H.I. Dale Jan 1998

The Elephants Of Africa, Robert H.I. Dale

Scholarship and Professional Work - LAS

Video review for the following title:

The Elephants of Africa: Nature. Produced by Scorer Associates, 1997. 55 minutes. $19.95 + $4.95 S/H.


Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch Jan 1998

Intraspecific Heterochrony And Life History Evolution: Decoupling Somatic And Sexual Development In A Facultatively Paedomorphic Salamander, Travis J. Ryan, Raymond D. Semlitsch

Scholarship and Professional Work - LAS

Morphological features such as size and shape are the most common focus in studies of heterochronic change. Frequently, these easily observed and measured features are treated as a major target of selection, potentially ignoring traits more closely related to fitness. We question the primacy of morphological data in studies of heterochrony, and instead suggest that principal sources of fitness, such as life history characteristics, are not only the chief targets of selection, but changes in them may necessitate changes in other (subordinate) elements of the organism. We use an experimental approach to investigate the timing of metamorphosis and maturation in ...


Elephant Days And Nights: Ten Years With The Indian Elephant, Robert H.I. Dale Jul 1997

Elephant Days And Nights: Ten Years With The Indian Elephant, Robert H.I. Dale

Scholarship and Professional Work - LAS

Book review for the following title:

Elephant Days and Nights. By Raman Sukumar (George B. Schaller, foreword), Oxford University Press, 1996, 200 pages.


The Asian Elephant: Ecology And Management, Robert H.I. Dale Apr 1997

The Asian Elephant: Ecology And Management, Robert H.I. Dale

Scholarship and Professional Work - LAS

Book review for the following title:

The Asian Elephant: Ecology and Management. By Raman Sukumar, Cambridge University Press, 1993, 282 pages. $34.95 hardcover


Some Children's Books About Elephants (1987-1997), Robert H.I. Dale Jan 1997

Some Children's Books About Elephants (1987-1997), Robert H.I. Dale

Scholarship and Professional Work - LAS

Literature review of children's books about elephants from the Indianapolis Public Library.


Studying Elephants: Awf Technical Handbook Series #7, Robert H.I. Dale Jan 1996

Studying Elephants: Awf Technical Handbook Series #7, Robert H.I. Dale

Scholarship and Professional Work - LAS

Book review for the following title:

Studying Elephants: AWF Technical Handbook Series #7. Edited by Kadzo Kangwana, Nairobi, Kenya: African Wildlife Foundation, 1996, 186 pages. $15 S&H.


Elephants, Robert H.I. Dale Jan 1995

Elephants, Robert H.I. Dale

Scholarship and Professional Work - LAS

Book review for the following title:

Elephants. By Clive Spinage, Kent, UK: Harcourt Brace & Co., 1994, 319 pages. £27.45.


Spatial Memory In Pigeons On A Four-Arm Radial Maze, Robert H.I. Dale Mar 1988

Spatial Memory In Pigeons On A Four-Arm Radial Maze, Robert H.I. Dale

Scholarship and Professional Work - LAS

Pigeon spatial memory was examined using a four-arm radial maze. The maze had four arms, spaced at 90° intervals, extending radially from a central choice area. Subjects were forced into three arms, then permitted two choices to enter the remaining ann. Five subjects chose accurately (90% correct) with delays of 5 min or less, their choices depended on extramaze cues, and the food in the target arm provided no essential cues. After an incorrect first choice, subjects' second choices were more accurate than chance. These data suggest that, while spatial memory has many similar characteristics in rats and pigeons, pigeon ...


Variations In Radial Maze Performance Under Different Levels Of Food And Water Deprivation, Robert H.I. Dale, William A. Roberts Mar 1986

Variations In Radial Maze Performance Under Different Levels Of Food And Water Deprivation, Robert H.I. Dale, William A. Roberts

Scholarship and Professional Work - LAS

Four groups of rats were tested on an eight-arm radial maze under a free-choice procedure. The subjects were maintained at either 80% or 100% of their preexperimental free-feeding weights through restricted access to either food or water. Water-deprived subjects received water in the maze; food-deprived subjects received food. Water-deprived subjects learned the task faster than food-deprived subjects. The four groups developed different response patterns. These were measured by the mean transition size, the average angular distance (in 45° units) between consecutively chosen arms. Rats foraging for food and water developed different search strategies, with water-deprived subjects exhibiting lower mean transition ...


Interactions Between Response Stereotypy And Memory Strategies On The Eight-Arm Radial Maze, Robert H.I. Dale, Nancy K. Innis Jan 1986

Interactions Between Response Stereotypy And Memory Strategies On The Eight-Arm Radial Maze, Robert H.I. Dale, Nancy K. Innis

Scholarship and Professional Work - LAS

Three groups of water-deprived rats collected water from the ends of the 8 arms of an 8-arm radial maze. Sighted subjects, and subjects blinded either with or without pre-enucleation experience on the radial maze, all retrieved the water efficiently. Most of the subjects exhibited the same response stereotypy, regularly choosing 8 adjacent arms of the maze, then stopping in the center of the maze. The strategies underlying this performance were analyzed by interrupting trials and rotating the maze 180° after the subject had made 3 choices. Sighted subjects depended on extramaze stimuli, naive-blind subjects depended on intramaze stimuli and experienced-blind ...


Spatial And Temporal Response Patterns On The Eight-Arm Radial Maze, Robert H.I. Dale Jan 1986

Spatial And Temporal Response Patterns On The Eight-Arm Radial Maze, Robert H.I. Dale

Scholarship and Professional Work - LAS

Six maze-experienced hooded rats were timed during five trials on which they collected water from all arms of an eight-arm radial maze, then made five more choices. All subjects frequently exhibited a “task-completion pause:” The subjects rarely spent more than 1 sec in the center of the maze between choices until they had entered all eight arms, then stopped in the center of the maze. In contrast, the time spent in each arm gradually increased until all of the water had been obtained, then decreased slightly. Four subjects began every trial by choosing eight consecutive adjacent arms. The task-completion pause ...


The Hippocampus As Episodic Encoder: Does It Play Tag?, Robert H.I. Dale Sep 1985

The Hippocampus As Episodic Encoder: Does It Play Tag?, Robert H.I. Dale

Scholarship and Professional Work - LAS

Rawlins’s characterization of the hippocampus as a “high-capacity, immediate-term memory store” captures the essential idea in a number of previous models. For example, Gaffan (1974), Gray (1984), Hirsh (1980), Kesner (Bierley, Kesner & Novak 1983), Olton (Olton, Becker & Handelmann 1979), Solomon (1980), and Winocur (1980) all agree that hippocampal animals show memory deficits when required to identify, for whatever reason, one specific event out of a list of recent events. Although these authors disagree on a number of details, Rawlins has identified their models common ground, the core of each model. (It is only fair to note that Gaffan has considerably modified his ideas about the hippocampus; cf. Gaffan, Saunders, Gaffan, Harrison, Shields & Owen 1984.)


Limitations On Spatial Memory In Mice, Robert H.I. Dale, Martin Bedard Jan 1984

Limitations On Spatial Memory In Mice, Robert H.I. Dale, Martin Bedard

Scholarship and Professional Work - LAS

Rats have an impressive ability to remember locations they have visited. Two experiments used an eight-arm radial maze to determine whether mice showed two important characteristics of this spatial memory: its durability, and its dependence on stimuli outside the maze (extreme stimuli). In Experiment 1, food-deprived mice were allowed to eat from four of the eight arms of the maze then, after delays of 5 sec, 1 min, or 5 min, they were permitted to choose the remaining arms. Choice accuracy declined significantly with the longer delays, but always remained above chance. In Experiment 2, the maze was rotated 180 ...


Dynamic Effects Of Food Magnitude On Interim-Terminal Interaction, Alliston K. Reid, Robert H.I. Dale Jan 1983

Dynamic Effects Of Food Magnitude On Interim-Terminal Interaction, Alliston K. Reid, Robert H.I. Dale

Scholarship and Professional Work - LAS

We tested the assumption of a facilitatory relation between periodic food presentation and schedule-induced drinking by examination of (a) elicited drinking, (b) drinking in anticipation of food delivery, and (c) possible indirect effects of food delivery on drinking. We exposed rats to a fixed-time 60-second schedule in which interfood intervals ended in either one or four food pellets with equal probability. In Phases 1 and 3, a stimulus signaled the magnitude of upcoming food presentation. In Phase 2, the stimulus was eliminated. Changes in drinking and "head-in-feeder" distributions within interfood intervals demonstrated that head-in-feeder was controlled directly by food presentation ...


Parallel-Arm Maze Performance Of Sighted And Blind Rats: Spatial Memory And Maze Structure, Robert H.I. Dale Jun 1982

Parallel-Arm Maze Performance Of Sighted And Blind Rats: Spatial Memory And Maze Structure, Robert H.I. Dale

Scholarship and Professional Work - LAS

Sighted and peripherally blinded groups of rats learned to obtain a small reward from each arm of an eight-arm parallel maze, and a sighted group was similarly trained on a radial maze. The parallel-sighted and parallel-blind groups were equally slow, and much slower than the radial-sighted group, to attain criterion performance. The three groups shared several response characteristics: selectively avoiding the most recently entered arms, frequently choosing adjacent arms, and an absence of 'spatial generalization' among the arms. The findings support a simple model proposing how subjects identify and choose among the maze-arms.