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| Author | Cameron, E.Z. | ||||
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 | 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 | ||||
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| Language | English | Summary Language | Original Title | ||
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| 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 | Bshary, R.; Wickler, W.; Fricke, H. | ||||
| Title |
Fish cognition: a primate's eye view | Type | Journal Article | ||
| Year | 2002 | Publication | Animal Cognition | Abbreviated Journal | Anim. Cogn. |
| Volume | 5 | Issue | 1 | Pages | 1-13 |
| Keywords | Animals; Cognition/*physiology; Evolution; Fishes/*physiology; Intelligence; Learning; Primates/*physiology; Social Behavior | ||||
| Abstract | We provide selected examples from the fish literature of phenomena found in fish that are currently being examined in discussions of cognitive abilities and evolution of neocortex size in primates. In the context of social intelligence, we looked at living in individualized groups and corresponding social strategies, social learning and tradition, and co-operative hunting. Regarding environmental intelligence, we searched for examples concerning special foraging skills, tool use, cognitive maps, memory, anti-predator behaviour, and the manipulation of the environment. Most phenomena of interest for primatologists are found in fish as well. We therefore conclude that more detailed studies on decision rules and mechanisms are necessary to test for differences between the cognitive abilities of primates and other taxa. Cognitive research can benefit from future fish studies in three ways: first, as fish are highly variable in their ecology, they can be used to determine the specific ecological factors that select for the evolution of specific cognitive abilities. Second, for the same reason they can be used to investigate the link between cognitive abilities and the enlargement of specific brain areas. Third, decision rules used by fish could be used as 'null-hypotheses' for primatologists looking at how monkeys might make their decisions. Finally, we propose a variety of fish species that we think are most promising as study objects. | ||||
| Address | University of Cambridge, Department of Zoology, Downing Street, Cambridge CB2 3EJ, UK. rb286@cam.ac.uk | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1435-9448 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11957395 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2617 | ||
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| Author | Czaran, T. | ||||
| Title |
Game theory and evolutionary ecology: Evolutionary Games & Population Dynamics by J. Hofbauer and K. Sigmund, and Game Theory & Animal Behaviour, edited by L.A. Dugatkin and H.K. Reeve | Type | Journal Article | ||
| Year | 1999 | Publication | Trends in Ecology & Evolution | Abbreviated Journal | Trends. Ecol. Evol |
| Volume | 14 | Issue | 6 | Pages | 246-247 |
| Keywords | Game theory; Evolutionary ecology; Population dynamics; Ethology | ||||
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| Notes | Approved | no | |||
| Call Number | refbase @ user @ | Serial | 485 | ||
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| Author | Cheng, K. | ||||
| Title |
Generalisation: mechanistic and functional explanations | Type | Journal Article | ||
| Year | 2002 | Publication | Animal Cognition | Abbreviated Journal | Anim. Cogn. |
| Volume | 5 | Issue | 1 | Pages | 33-40 |
| Keywords | Adaptation, Physiological; Animals; Bees/*physiology; Cognition; Evolution; Models, Psychological | ||||
| Abstract | An overview of mechanistic and functional accounts of stimulus generalisation is given. Mechanistic accounts rely on the process of spreading activation across units representing stimuli. Different models implement the spread in different ways, ranging from diffusion to connectionist networks. A functional account proposed by Shepard analyses the probabilistic structure of the world for invariants. A universal law based on one such invariant claims that under a suitable scaling of the stimulus dimension, generalisation gradients should be approximately exponential in shape. Data from both vertebrates and invertebrates so far uphold Shepard's law. Some data on spatial generalisation in honeybees are presented to illustrate how Shepard's law can be used to determine the metric for combining discrepancies in different stimulus dimensions. The phenomenon of peak shift is discussed. Comments on mechanistic and functional approaches to generalisation are given. | ||||
| Address | Department of Psychology, Macquarie University, Sydney, NSW 2109, Australia. kcheng@axon.bhs.mq.edu.au | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | 1435-9448 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11957400 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2612 | ||
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| Author | Bouchard, T.J.J.; Loehlin, J.C. | ||||
| Title |
Genes, evolution, and personality | Type | Journal Article | ||
| Year | 2001 | Publication | Behavior Genetics | Abbreviated Journal | Behav Genet |
| Volume | 31 | Issue | 3 | Pages | 243-273 |
| Keywords | Animals; *Evolution; Genetics, Behavioral; Humans; Individuality; Personality/*genetics; Twin Studies | ||||
| Abstract | There is abundant evidence, some of it reviewed in this paper, that personality traits are substantially influenced by the genes. Much remains to be understood about how and why this is the case. We argue that placing the behavior genetics of personality in the context of epidemiology, evolutionary psychology, and neighboring psychological domains such as interests and attitudes should help lead to new insights. We suggest that important methodological advances, such as measuring traits from multiple viewpoints, using large samples, and analyzing data by modern multivariate techniques, have already led to major changes in our view of such perennial puzzles as the role of “unshared environment” in personality. In the long run, but not yet, approaches via molecular genetics and brain physiology may also make decisive contributions to understanding the heritability of personality traits. We conclude that the behavior genetics of personality is alive and flourishing but that there remains ample scope for new growth and that much social science research is seriously compromised if it does not incorporate genetic variation in its explanatory models. | ||||
| Address | Department of Psychology. University of Minnesota, Minneapolis 55455, USA. bouch001@tc.umn.edu | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | 0001-8244 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:11699599 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 4142 | ||
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| Author | Cilnis, M.J.; Kang, W.; Weaver, S.C. | ||||
| Title |
Genetic conservation of Highlands J viruses | Type | Journal Article | ||
| Year | 1996 | Publication | Virology | Abbreviated Journal | Virology |
| Volume | 218 | Issue | 2 | Pages | 343-351 |
| Keywords | Alphavirus/*genetics; Alphavirus Infections/transmission/veterinary/virology; Amino Acid Sequence; Animals; Base Sequence; Conserved Sequence; Disease Outbreaks; Encephalitis, Viral/veterinary/virology; *Evolution, Molecular; Horses; Molecular Sequence Data; Phylogeny; RNA, Viral/genetics; Sequence Alignment; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Turkeys; Variation (Genetics)/*genetics | ||||
| Abstract | We studied molecular evolution of the mosquito-borne alphavirus Highlands J (HJ) virus by sequencing PCR products generated from 19 strains isolated between 1952 and 1994. Sequences of 1200 nucleotides including portions of the E1 gene and the 3' untranslated region revealed a relatively slow evolutionary rate estimated at 0.9-1.6 x 10(-4) substitutions per nucleotide per year. Phylogenetic trees indicated that all HJ viruses descended from a common ancestor and suggested the presence of one dominant lineage in North America. However, two or more minor lineages probably circulated simultaneously for periods of years to a few decades. Strains isolated from a horse suffering encephalitis, and implicated in a recent turkey outbreak, were not phylogenetically distinct from strains isolated in other locations during the same time periods. Our findings are remarkably similar to those we obtained previously for another North American alphavirus, eastern equine encephalomyelitis virus, with which Highlands J shares primary mosquito and avian hosts, geographical distribution, and ecology. These results support the hypotheses that the duration of the transmission season affects arboviral evolutionary rates and vertebrate host mobility influences genetic diversity. | ||||
| Address | Department of Biology, University of California, San Diego, La Jolla 92093-0116, USA | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0042-6822 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:8610461 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 2657 | ||
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| Author | Hamilton, W.D. | ||||
| Title |
Geometry for the selfish herd | Type | Journal Article | ||
| Year | 1971 | Publication | Journal of theoretical biology | Abbreviated Journal | J. Theor. Biol. |
| Volume | 31 | Issue | 2 | Pages | 295-311 |
| Keywords | Animals; Anura; *Behavior, Animal; Breeding; Communication; Evolution; Fear; Metallurgy; *Models, Biological; Probability; Snakes; *Spatial Behavior | ||||
| Abstract | This paper presents an antithesis to the view that gregarious behaviour is evolved through benefits to the population or species. Following Galton (1871) and Williams (1964) gregarious behaviour is considered as a form of cover-seeking in which each animal tries to reduce its chance of being caught by a predator. It is easy to see how pruning of marginal individuals can maintain centripetal instincts in already gregarious species; some evidence that marginal pruning actually occurs is summarized. Besides this, simply defined models are used to show that even in non-gregarious species selection is likely to favour individuals who stay close to others. Although not universal or unipotent, cover-seeking is a widespread and important element in animal aggregation, as the literature shows. Neglect of the idea has probably followed from a general disbelief that evolution can be dysgenic for a species. Nevertheless, selection theory provides no support for such disbelief in the case of species with outbreeding or unsubdivided populations. The model for two dimensions involves a complex problem in geometrical probability which has relevance also in metallurgy and communication science. Some empirical data on this, gathered from random number plots, is presented as of possible heuristic value. |
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0022-5193 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:5104951 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 771 | ||
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| Author | Hampton, R.R.; Sherry, D.F.; Shettleworth, S.J.; Khurgel, M.; Ivy, G. | ||||
| Title |
Hippocampal volume and food-storing behavior are related in parids | Type | Journal Article | ||
| Year | 1995 | Publication | Brain, behavior and evolution | Abbreviated Journal | Brain Behav Evol |
| Volume | 45 | Issue | 1 | Pages | 54-61 |
| Keywords | Animals; Appetitive Behavior/*physiology; Birds/*anatomy & histology; Brain Mapping; Evolution; Food Preferences/physiology; Hippocampus/*anatomy & histology; Mental Recall/*physiology; Orientation/*physiology; Predatory Behavior/physiology; Social Environment; Species Specificity | ||||
| Abstract | The size of the hippocampus has been previously shown to reflect species differences and sex differences in reliance on spatial memory to locate ecologically important resources, such as food and mates. Black-capped chickadees (Parus atricapillus) cached more food than did either Mexican chickadees (P. sclateri) or bridled titmice (P. wollweberi) in two tests of food storing, one conducted in an aviary and another in smaller home cages. Black-capped chickadees were also found to have a larger hippocampus, relative to the size of the telencephalon, than the other two species. Differences in the frequency of food storing behavior among the three species have probably produced differences in the use of hippocampus-dependent memory and spatial information processing to recover stored food, resulting in graded selection for size of the hippocampus. | ||||
| Address | Department of Psychology, University of Toronto, Ontario, Canada | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0006-8977 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:7866771 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 379 | ||
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| Author | Hare, B.; Tomasello, M. | ||||
| Title |
Human-like social skills in dogs? | Type | Journal Article | ||
| Year | 2005 | Publication | Trends in Cognitive Sciences | Abbreviated Journal | Trends. Cognit. Sci. |
| Volume | 9 | Issue | 9 | Pages | 439-444 |
| Keywords | *Animal Communication; Animals; *Behavior, Animal; Cognition/*physiology; Dogs; *Evolution; Humans; *Social Behavior | ||||
| Abstract | Domestic dogs are unusually skilled at reading human social and communicative behavior--even more so than our nearest primate relatives. For example, they use human social and communicative behavior (e.g. a pointing gesture) to find hidden food, and they know what the human can and cannot see in various situations. Recent comparisons between canid species suggest that these unusual social skills have a heritable component and initially evolved during domestication as a result of selection on systems mediating fear and aggression towards humans. Differences in chimpanzee and human temperament suggest that a similar process may have been an important catalyst leading to the evolution of unusual social skills in our own species. The study of convergent evolution provides an exciting opportunity to gain further insights into the evolutionary processes leading to human-like forms of cooperation and communication. | ||||
| Address | Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, Germany. hare@eva.mpg.de | ||||
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| Language | English | Summary Language | Original Title | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1364-6613 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:16061417 | Approved | no | ||
| Call Number | refbase @ user @ | Serial | 546 | ||
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| Author | Berger, J. | ||||
| Title |
Induced abortion and social factors in wild horses | Type | Journal Article | ||
| Year | 1983 | Publication | Nature | Abbreviated Journal | Nature |
| Volume | 303 | Issue | 5912 | Pages | 59-61 |
| Keywords | Abortion, Induced/*veterinary; Abortion, Veterinary/*etiology; Aggression/physiology; Animals; Evolution; Female; Horses/*physiology; Humans; Pregnancy; Sexual Behavior, Animal/*physiology | ||||
| Abstract | Much evidence now suggests that the postnatal killing of young in primates and carnivores, and induced abortions in some rodents, are evolved traits exerting strong selective pressures on adult male and female behaviour. Among ungulates it is perplexing that either no species have developed convergent tactics or that these behaviours are not reported, especially as ungulates have social systems similar to those of members of the above groups. Only in captive horses (Equus caballus) has infant killing been reported. It has been estimated that 40,000 wild horses live in remote areas of the Great Basin Desert of North America (US Department of Interior (Bureau of Land Management), unpublished report), where they occur in harems (females and young) defended by males. Here I present evidence that, rather than killing infants directly, invading males induce abortions in females unprotected by their resident stallions and these females are then inseminated by the new males. | ||||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0028-0836 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | PMID:6682487 | Approved | no | ||
| Call Number | Equine Behaviour @ team @ | Serial | 4365 | ||
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