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Author Gallistel, C.R.; Cramer, A.E. openurl 
  Title Computations on metric maps in mammals: getting oriented and choosing a multi-destination route Type Journal Article
  Year 1996 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol  
  Volume (up) 199 Issue Pt 1 Pages 211-217  
  Keywords Animals; Brain/physiology; Cercopithecus aethiops; Cognition/*physiology; Humans; Mammals/*physiology; Movement; Orientation/*physiology; Rats; Space Perception; Visual Pathways/*physiology  
  Abstract The capacity to construct a cognitive map is hypothesized to rest on two foundations: (1) dead reckoning (path integration); (2) the perception of the direction and distance of terrain features relative to the animal. A map may be constructed by combining these two sources of positional information, with the result that the positions of all terrain features are represented in the coordinate framework used for dead reckoning. When animals need to become reoriented in a mapped space, results from rats and human toddlers indicate that they focus exclusively on the shape of the perceived environment, ignoring non-geometric features such as surface colors. As a result, in a rectangular space, they are misoriented half the time even when the two ends of the space differ strikingly in their appearance. In searching for a hidden object after becoming reoriented, both kinds of subjects search on the basis of the object's mapped position in the space rather than on the basis of its relationship to a goal sign (e.g. a distinctive container or nearby marker), even though they have demonstrably noted the relationship between the goal and the goal sign. When choosing a multidestination foraging route, vervet monkeys look at least three destinations ahead, even though they are only capable of keeping a maximum of six destinations in mind at once.  
  Address Department of Psychology, University of California, Los Angeles 90095, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8576692 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2757  
Permanent link to this record
 

 
Author Etienne, A.S.; Maurer, R.; Seguinot, V. openurl 
  Title Path integration in mammals and its interaction with visual landmarks Type Journal Article
  Year 1996 Publication The Journal of Experimental Biology Abbreviated Journal J Exp Biol  
  Volume (up) 199 Issue Pt 1 Pages 201-209  
  Keywords Animals; Cognition/physiology; Cricetinae; Gerbillinae; Humans; Locomotion/*physiology; Mammals/*physiology; Mesocricetus; Mice; Proprioception/physiology; Rats; Visual Pathways/*physiology; Visual Perception/*physiology  
  Abstract During locomotion, mammals update their position with respect to a fixed point of reference, such as their point of departure, by processing inertial cues, proprioceptive feedback and stored motor commands generated during locomotion. This so-called path integration system (dead reckoning) allows the animal to return to its home, or to a familiar feeding place, even when external cues are absent or novel. However, without the use of external cues, the path integration process leads to rapid accumulation of errors involving both the direction and distance of the goal. Therefore, even nocturnal species such as hamsters and mice rely more on previously learned visual references than on the path integration system when the two types of information are in conflict. Recent studies investigate the extent to which path integration and familiar visual cues cooperate to optimize the navigational performance.  
  Address Laboratoire d'Ethologie, FPSE, Universite de Geneve, Carouge, Switzerland  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0949 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:8576691 Approved no  
  Call Number Equine Behaviour @ team @ Serial 2758  
Permanent link to this record
 

 
Author Cameron, E.Z. doi  openurl
  Title Facultative adjustment of mammalian sex ratios in support of the Trivers-Willard hypothesis: evidence for a mechanism Type Journal Article
  Year 2004 Publication Proceedings. Biological sciences / The Royal Society Abbreviated Journal Proc Biol Sci  
  Volume (up) 271 Issue 1549 Pages 1723-1728  
  Keywords Age Factors; Animals; Body Constitution; *Evolution; Female; Glucose/metabolism/physiology; Litter Size; Male; Mammals/*physiology; *Models, Biological; Reproduction/physiology; Seasons; Sex Factors; *Sex Ratio; Time Factors  
  Abstract Evolutionary theory predicts that mothers of different condition should adjust the birth sex ratio of their offspring in relation to future reproductive benefits. Published studies addressing variation in mammalian sex ratios have produced surprisingly contradictory results. Explaining the source of such variation has been a challenge for sex-ratio theory, not least because no mechanism for sex-ratio adjustment is known. I conducted a meta-analysis of previous mammalian sex-ratio studies to determine if there are any overall patterns in sex-ratio variation. The contradictory nature of previous results was confirmed. However, studies that investigated indices of condition around conception show almost unanimous support for the prediction that mothers in good condition bias their litters towards sons. Recent research on the role of glucose in reproductive functioning have shown that excess glucose favours the development of male blastocysts, providing a potential mechanism for sex-ratio variation in relation to maternal condition around conception. Furthermore, many of the conflicting results from studies on sex-ratio adjustment would be explained if glucose levels in utero during early cell division contributed to the determination of offspring sex ratios.  
  Address Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria 0002, South Africa. ezcameron@zoology.up.ac.za  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-8452 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15306293 Approved no  
  Call Number refbase @ user @ Serial 413  
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Author Novacek, M.J. doi  openurl
  Title Mammalian phylogeny: shaking the tree Type Journal Article
  Year 1992 Publication Nature Abbreviated Journal Nature  
  Volume (up) 356 Issue 6365 Pages 121-125  
  Keywords Animals; Evolution; Fossils; Mammals/classification/*genetics; *Phylogeny  
  Abstract Recent palaeontological discoveries and the correspondence between molecular and morphological results provide fresh insight on the deep structure of mammalian phylogeny. This new wave of research, however, has yet to resolve some important issues.  
  Address American Museum of Natural History, New York 10024  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:1545862 Approved no  
  Call Number Equine Behaviour @ team @ Serial 3546  
Permanent link to this record
 

 
Author Palme, R.; Rettenbacher, S.; Touma, C.; El-Bahr, S.M.; Mostl, E. doi  openurl
  Title Stress hormones in mammals and birds: comparative aspects regarding metabolism, excretion, and noninvasive measurement in fecal samples Type Journal Article
  Year 2005 Publication Annals of the New York Academy of Sciences Abbreviated Journal Ann N Y Acad Sci  
  Volume (up) 1040 Issue Pages 162-171  
  Keywords Adrenal Glands/chemistry/metabolism; Animals; Birds; Catecholamines/analysis/chemistry/*metabolism; Feces/*chemistry; Glucocorticoids/analysis/chemistry/*metabolism; Hormones/analysis/metabolism; Mammals; Species Specificity; Stress/*metabolism  
  Abstract A multitude of endocrine mechanisms are involved in coping with challenges. Front-line hormones to overcome stressful situations are glucocorticoids (GCs) and catecholamines (CAs). These hormones are usually determined in plasma samples as parameters of adrenal activity and thus of disturbance. GCs (and CAs) are extensively metabolized and excreted afterwards. Therefore, the concentration of GCs (or their metabolites) can be measured in various body fluids or excreta. Above all, fecal samples offer the advantages of easy collection and a feedback-free sampling procedure. However, large differences exist among species regarding the route and time course of excretion, as well as the types of metabolites formed. Based on information gained from radiometabolism studies (reviewed in this paper), we recently developed and successfully validated different enzyme immunoassays that enable the noninvasive measurement of groups of cortisol or corticosterone metabolites in animal feces. The determination of these metabolites in fecal samples can be used as a powerful tool to monitor GC production in various species of domestic, wildlife, and laboratory animals.  
  Address Institute of Biochemistry, Department of Natural Sciences, University of Veterinary Medicine, Vienna, Austria. rupert.palme@vu-wien.ac.at  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0077-8923 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:15891021 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4083  
Permanent link to this record
 

 
Author Touma, C.; Palme, R. doi  openurl
  Title Measuring fecal glucocorticoid metabolites in mammals and birds: the importance of validation Type Journal Article
  Year 2005 Publication Annals of the New York Academy of Sciences Abbreviated Journal Ann N Y Acad Sci  
  Volume (up) 1046 Issue Pages 54-74  
  Keywords Animals; Birds/*metabolism; Circadian Rhythm; Feces/*chemistry; Glucocorticoids/*analysis; Mammals/*metabolism; Reproducibility of Results; Seasons; Sex Factors  
  Abstract In recent years, the noninvasive monitoring of steroid hormone metabolites in feces of mammals and droppings of birds has become an increasingly popular technique. It offers several advantages and has been applied to a variety of species under various settings. However, using this technique to reliably assess an animal's adrenocortical activity is not that simple and straightforward to apply. Because clear differences regarding the metabolism and excretion of glucocorticoid metabolites (GCMs) exist, a careful validation for each species and sex investigated is obligatory. In this review, general analytical issues regarding sample storage, extraction procedures, and immunoassays are briefly discussed, but the main focus lies on experiments and recommendations addressing the validation of fecal GCM measurements in mammals and birds. The crucial importance of scrutinizing the physiological and biological validity of fecal GCM analyses in a given species is stressed. In particular, the relevance of the technique to detect biologically meaningful alterations in adrenocortical activity must be shown. Furthermore, significant effects of the animals' sex, the time of day, season, and different life history stages are discussed, bringing about the necessity to seriously consider possible sex differences as well as diurnal and seasonal variations. Thus, comprehensive information on the animals' biology and stress physiology should be carefully taken into account. Together with an extensive physiological and biological validation, this will ensure that the measurement of fecal GCMs can be used as a powerful tool to assess adrenocortical activity in diverse investigations on laboratory, companion, farm, zoo, and wild animals.  
  Address Max Planck Institute of Psychiatry, Department of Behavioral Neuroendocrinology, Kraepelinstrasse 2-10, D-80804 Munich, Germany. touma@mpipsykl.mpg.de  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0077-8923 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:16055843 Approved no  
  Call Number Equine Behaviour @ team @ Serial 4073  
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