Variability in sensory ecology: expanding the bridge between physiology and evolutionary biology
Sensory organs represent the interface between the central nervous system of organisms and the environment in which they live. To date, we still lack a true integration of ecological and evolutionary perspectives in our understanding of many sensory systems. We argue that scientists working in sensory ecology should expand the bridge between sensory and evolutionary […]
History and future of comparative analyses in sleep research
The comparative methods of evolutionary biology are a useful tool for investigating the functions of sleep. These techniques can help determine whether experimental results, derived from a single or few species, apply broadly across a specified group of animals. In this way, comparative analysis is a powerful complement to experimentation. The variation in the time […]
Why in earth? Dustbathing behaviour in jungle and domestic fowl reviewed from a Tinbergian and animal welfare perspective
Dustbathing has been the subject of much research in captive birds. In the present review we bring together the studies of domestic fowl (Gallus gallus domesticus) and jungle fowl (G. gallus) to provide a more complete picture of the behaviour. Dustbathing is discussed from the four aspects suggested by Tinbergen [Tinbergen, N., 1963. On aims […]
The roles of phylogeny and sociality in the evolution of social play in muroid rodents
A composite index incorporating the frequency and structure (target, type of defence, etc.) of play fighting was used to compare the complexity of such play in 13 species of muroid rodents whose behaviour has been previously described. A phylogenetic comparison of the distribution of the complexity of play fighting revealed that relatedness did not predict […]
Comparative Methods with Sampling Error and Within-Species Variation: Contrasts Revisited and Revised
Comparative methods analyses have usually assumed that the species phenotypes are the true means for those species. In most analyses, the actual values used are means of samples of modest size. The covariances of contrasts then involve both the covariance of evolutionary changes and a fraction of the within‐species phenotypic covariance, the fraction depending on […]
Phylogenies and the Comparative Method
Comparative studies of the relationship between two phenotypes, or between a phenotype and an environment, are frequently carried out by invalid statistical methods. Most regression, correlation, and contingency table methods, including nonparametric methods, assume that the points are drawn independently from a common distribution. When species are taken from a branching phylogeny, they are manifestly […]
A comparative study of white blood cell counds and disease risk in carnivores.
In primates, baseline levels of white blood cell (WBC) counts are related to mating promiscuity. It was hypothesized that differences in the primate immune system reflect pathogen risks from sexually transmitted diseases (STDs). Here, we test for the generality of this result by examining hypotheses involving behavioural, ecological and life-history factors in carnivores. Again, we […]
A comparison of four corvid species in a working and reference memory task using a radial maze
Birds were tested in an open-room radial maze with learned spatial locations that varied from trial to trial (working memory) and locations that remained spatially stable (reference memory). Three of the species, the Clark’s nutcracker (Nucifraga columbiana), pinyon jay (Gymnorhinus cyanocephalus), and Western scrub jay (Aphelocoma coerulescens) store food to varying degrees. The other species, […]
UVS is Rare in Seabirds
Ultraviolet-sensitive vision (UVS), believed to have evolved from an ancestral state of violet-sensitive vision (VS), is widespread among terrestrial birds, where it is thought to play a role in orientation, foraging, and sexual selection. Less is known, however, about the distribution and significance of UVS in seabirds. To date UVS has been definitively demonstrated only […]
D.G.M. Wood-Gush Memorial Lecture: An applied ethologist looks at the question “Why?”
The question “Why does an animal behave as it does?” can be answered in terms of ontogeny, function, phylogeny and causation. The achievements of applied ethology relative to those four approaches are reviewed, gaps in our knowledge are identified and predictions for fruitful avenues of future research are made. Ontogenic studies have been useful in […]