George Uetz - Academia.edu (original) (raw)

Papers by George Uetz

Animal Behaviour, Apr 1, 1999

Behavioral Ecology and Sociobiology, Mar 23, 2000

Springer eBooks, 1991

Habitat structure and spider foraging. GW Uetz POPUL. COMMUNITY BIOL. SER., 325-348, 1991. D 0466... more Habitat structure and spider foraging. GW Uetz POPUL. COMMUNITY BIOL. SER., 325-348, 1991. D 04660 Arachnids; Z 05199 Feeding; Y 25492 Invertebrates(excluding insects).

Journal of the Acoustical Society of America, Apr 1, 2015

Vibration is an important part of the sensory world in spiders, and many species have adapted vib... more Vibration is an important part of the sensory world in spiders, and many species have adapted vibration as a major part of their conspecific communication. While nearly all male wolf spiders produce vibrations during courtship, the “purring” wolf spider, Gladicosa gulosa, also produces an acoustic signal in conjunction with its vibratory display. However, with limited previous research on this species, the evolutionary significance of this component remains unknown. Given that spiders are not known to possess sensory structures for directly perceiving airborne sound, this raises a number of questions about the production, reception, and possible role of the signal. We measured male signal production and male/female responses to isolated acoustic signals on both vibrating (paper) and non-vibrating (granite) substrates. We found that male signals, both vibratory and acoustic, are only present in vibrating substrates. We also found significant differences in phonotaxis based on sex of the focal individual, stimulus type, and substrate type. These results suggest that the substrate plays an important role in both production and reception of the acoustic signal, and that under certain conditions, acoustic signaling may have a role in the communication network in this species.

Springer eBooks, 1986

Environmental and Genetic Influences on the Social Grouping Tendency of a Communal Spider George ... more Environmental and Genetic Influences on the Social Grouping Tendency of a Communal Spider George W. Uetz Thomas C. Kane Gail E. Stratton* Michael J. Benton* Department of Biological Sciences University of Cincinnati Cincinnati. Ohio 45221 Introduction Within the study of ...

Ecoscience, Sep 1, 2009

Abstract: Animals subject to environmental stress often exhibit higher levels of developmental in... more Abstract: Animals subject to environmental stress often exhibit higher levels of developmental instability, frequently measured as Fluctuating Asymmetry (FA), small, random deviations from perfect left-right symmetry in bilaterally symmetrical animals. We used FA measurement as a means of determining the impact of a catastrophic ecosystem disturbance (a major Class F3 tornado) on populations of Schizocosa ocreata, a common forest-dwelling wolf spider. As FA in sexually selected ornamental traits in males has been shown in some (but not all) species studied to be a sensitive indicator of environmental stress, we measured FA of foreleg tufts in male S. ocreata. Spiders from the first post-disturbance generation were collected by pitfall trapping in the spring of 2000, and preserved specimens were photographed and measured using digital imaging. Spiders from disturbed and undisturbed areas within the forest did not differ significantly in body size parameters, although body condition varied significantly between sites. Signed (R-L) FA of male tuft area was normally distributed with a mean of zero, indicating “ideal” or “true” FA, a reflection of Developmental Instability (DI). Although tuft area was not significantly different between sites, tuft area FA in male S. ocreata was significantly higher in the disturbed site, suggesting that ecosystem-level stress may produce higher levels of developmental instability in arthropod populations. Results of our study indicate that FA in this secondary sexual character (male leg tufts) is a more sensitive indicator of putative environmental stress than a non-sexual trait (femur length). To our knowledge, this is the first study of FA in invertebrates associated with environmental stress from a catastrophic natural disturbance. Nomenclature: Dondale & Redner, 1990.

Animal Behaviour, Jul 1, 2016

Ethology, Jun 1, 2008

In many species, expression of elaborate male characteristics likely represents a balance between... more In many species, expression of elaborate male characteristics likely represents a balance between sexual selection and natural selection via predation, as male traits selected to elicit rapid detection or response on the part of females also increase detection by predators. Predation costs are frequently inferred, but the underlying mechanisms associated with specific traits have rarely been directly explored. Males of the wolf spider Schizocosa ocreata (Araneae: Lycosidae) exhibit a sexually selected signaling trait (dark tufts of bristles) on their forelegs, and are sympatric with a number of visually hunting generalist predators, including cannibalistic conspecifics, that may impact spider survival. Here we use latency of orientation response of the American toad, Bufo americanus (Anura: Bufonidae), to video, ‘virtual’ courting S. ocreata male stimuli as an index of predator detection, and latency of orientation response of female S. ocreata to the same stimuli as an index of conspecific detection. When compared with stimuli representing the population average, elimination of the signal trait had no significant effect on predator detection but did increase latency to orient in conspecifics. Increasing the size of the signal trait had no effect on conspecific detection but did significantly reduce latency to orient for predatory toads. Results clearly indicate that for a courting male spider of a given size and vigor level, variation in the expression of a secondary sexual characteristic alone can incur differential direct costs and benefits by influencing latency of orientation to visual signals by predators and conspecifics.

Journal of Insect Behavior, Jul 1, 2004

Journal of Chemical Ecology, Jun 1, 2004

Chemical signals from female wolf spiders that elicit exploratory behavior and courtship in males... more Chemical signals from female wolf spiders that elicit exploratory behavior and courtship in males are often assumed to be species-specific, but males of some species court in response to silk cues deposited by closely related heterospecific females. Such is the case with the wolf spiders Schizocosa ocreata and S. rovneri, ethospecies reproductively isolated on the basis of differences in behavioral mechanisms during courtship. We explored whether male S. ocreata and S. rovneri reciprocally discriminate species-specific chemical or mechanical cues associated with female silk by using male behavioral response as an assay. Males were exposed to stimulus treatment categories including silk, washed silk, silk extract, and appropriate controls within conspecific or heterospecific female stimulus categories. Male S. ocreata and S. rovneri did not discriminate between conspecific or heterospecific female stimuli, and courtship intensity was greatest on untreated silk. There were no differences in latency to begin courtship or in rates of courtship behaviors attributed to species origin of silk. However, silk treatment (washed silk, extract) had a significant effect on display and exploratory behaviors (e.g., chemoexplore) in both species. Methanol extraction of female silk successfully removed or inactivated a component necessary to elicit active courtship, but extraction did not significantly reduce exploratory behavior, suggesting that a separate compound may be responsible for releasing this behavior. Together, these experiments support the characterization of S. ocreata and S. rovneri as ethospecies reproductively isolated only by female discrimination of species-specific male courtship, and indicate that chemical, but not mechanical cues associated with silk are critical for eliciting male courtship in both species.

American Midland Naturalist, 1984

... Succession, diversity and trophic relationship of some soil animals in decomposing leaf litte... more ... Succession, diversity and trophic relationship of some soil animals in decomposing leaf litter. ... between woodland cryptostigmata species diversity and the diversity of soil and litter microhabitats. ... The distributional ecology of spiders in the old-field succession of the Piedmont ...

Behavioral Ecology and Sociobiology, Nov 29, 2006

Individual variation in female preference for male traits may influence mate choice, especially i... more Individual variation in female preference for male traits may influence mate choice, especially if benefits and costs of choosiness vary with the range of available males or reproductive timing. We examined variation in female preference for male leg tuft size in Schizocosa ocreata (Hentz) wolf spiders with video playback. Dichotomous (simultaneous) choice test experiments included all possible combinations of four stimuli (i.e., modified versions of the same video male stimulus): average tuft size (control), reduced (−25%), enlarged (+25%), and no tufts (removed). Females exhibited a directional preference for larger tuft size independent of the nature of the choice (except for reduced tufts vs no tufts where no difference was seen). Female preference in the short term (over a period of 4 days) was also highly repeatable for control vs reduced tufts, but not for control vs enlarged tufts. Responses of females in 'no-choice' presentations of a single (control) male stimulus varied with age postmaturity; females were less receptive in weeks 1 and 2, highly receptive at week 3, and less thereafter. Mated females were least receptive and most aggressive towards a male stimulus. Females offered choices repeatedly at different ages post-maturity consistently preferred the control male vs reduced tufts over all 3 weeks but varied in their preference for enlarged tufts vs control male. In the first 2 weeks, females preferred the enlarged tuft male stimulus, but showed no preference by the third week. Females tested in week 4 showed no preference in either choice. Results suggest that the potential interaction between female preference for male traits and female reproductive timing may be a critical consideration in mate choice.

Urban Ecology, Jun 1, 1985

Journal of Arachnology, Sep 30, 2020

Abstract. In many spiders, limb autotomy (self-amputation) is a common anti-predator behavior. Wh... more Abstract. In many spiders, limb autotomy (self-amputation) is a common anti-predator behavior. While many species are able to regenerate lost limbs without apparent fitness costs, there are demonstrable costs in others. Previous studies have shown males of the brush-legged wolf spider Schizocosa ocreata (Hentz, 1844) incur reduced mating success after autotomy and/or regeneration of their decorated forelimbs, which affects visual courtship displays. However, because courtship of male S. ocreata is multimodal and contains vibratory/seismic signals, communication in this channel might also be affected. We recorded female receptivity to isolated male vibratory/seismic courtship signals from: males with intact forelimbs (control), males with a regenerated forelimb, and males missing a forelimb. Females were more receptive to isolated vibratory/seismic signals of intact males over males missing a foreleg, but not males that regenerated a foreleg. Although initial size and body condition did not differ among treatments, regeneration of a limb had a significant negative impact on growth increment from penultimate instar to adult, suggesting a possible physiological cost of regeneration. To investigate the impact of autotomy and regeneration on vibratory/seismic signals, we used laser Doppler vibrometry (LDV). Analysis of overall signal amplitude across treatments revealed significantly reduced amplitude for males with regenerated limbs, despite these males having receptivity responses statistically similar to control males. Analyses of component elements of vibratory/seismic signals showed three (of four) had significantly reduced amplitude in males regenerating limbs. These results demonstrate a potential fitness impact of autotomy and regeneration on the vibratory/seismic component of male courtship signals.

Journal of Zoology, Apr 1, 1995

The theraphosid spider Theraphosa leblondi (Latreille) produces a sibilant, hissing sound during ... more The theraphosid spider Theraphosa leblondi (Latreille) produces a sibilant, hissing sound during defensive displays. This sound is produced using a previously undescribed method of stridulation: setal entanglement. The opposing surfaces of the femora of the pedipalps, ...

Animal Cognition, Aug 24, 2016

Behavioral Ecology and Sociobiology, Apr 1, 1988

Mexico were studied to test predictions of risksensitive foraging theory: 1. group foraging incre... more Mexico were studied to test predictions of risksensitive foraging theory: 1. group foraging increases prey capture/individual, and reduces prey variance; 2. spiders should be expected to exhibit risk-averse behavior (forage in groups) when the average level of prey exceeds individual needs, and exhibit risk-prone behavior (forage solitarily) when prey are scarce. Laboratory and field studies show that group foraging increases capture efficiency and reduces variability in prey captured per spider. In desert/mesquite grassland habitat, where prey availability is low, M. atascadero forage solitarily in most cases. In tropical rainforest/agriculture sites, M. incrassata forage in large colonies of thousands of webs. In intermediate habitats, M. spinipes forages solitarily or in groups, depending on prey availability. Over a range of sites with varying levels of prey, M. spinipes shifts from a risk-prone to a risk-averse group foraging strategy as prey increases. Group foraging behavior observed in colonial Metepeira fits the predictions of risk-sensitive foraging models. These findings explain why spiders tend to group webs together only in areas of superabundant prey. The role of risk-sensitivity in the evolution of coloniality in spiders is discussed.