@article {1393,
	title = {Effect of vagility potential on dispersal and speciation in rainforest insects},
	journal = {Journal of Evolutionary Biology},
	volume = {17},
	number = {5},
	year = {2004},
	pages = {994-1006},
	keywords = {biogeography, dispersal, Dung beetles, evolution, rainforest, speciation, vagility, vicariance},
	author = {Bouchard, P. and Brooks, D. R.}
}
@article {1792,
	title = {The evolution of male genitalia: patterns of genetic variation and covariation in the genital sclerites of the dung beetle Onthophagus taurus},
	journal = {Journal of Evolutionary Biology},
	volume = {18},
	year = {2005},
	pages = {1281-1292},
	abstract = {Three main hypotheses, have been invoked to explain divergent genital evolution, the lock and key, pleiotropy, and sexual selection hypotheses, each of which make different predictions about how genital traits are inherited. Here we used a half-sib breeding design to examine the patterns of genetic variation and covariation between male genital sclerites, and their covariance with general body morphology in the dung beetle Onthophagus taurus. We found CVA{\textquoteright}s and CVP{\textquoteright}s were similar for both genital and general morphological traits and that CVR{\textquoteright}s were large for both trait types. We found that male genital sclerites were negatively genetically correlated with general morphological traits. Variation in male genital morphology has direct implications for a male{\textquoteright}s fertilization success and the resulting sexual selection acting on male genitalia is predicted to maintain high levels of additive genetic variance. Contrary to this prediction, we found that individual genital sclerites all had low levels of additive genetic variance and large maternal and environmental sources of variation. Our data suggest that the genital sclerites in O. taurus are not inherited independently but as a genetically integrated unit. More import- antly, the way the different sclerites function to influence male fertilization success reflects this genetic integration. Even though levels of VA in individual genital sclerites may be low, there may still be sufficient VA in multivariate trait space for selection to generate evolutionary change in the overall morphology of male genitalia. },
	keywords = {additive genetic variation, genetic correlation, genital evolution, maternal effects, morphological integration, Onthophagus taurus, pleiotropy},
	author = {House, Clarissa M. and Simmons, Leigh W.}
}
@article {1819,
	title = {Confidence of paternity and paternal care: covariation revealed through the experimental manipulation of the mating system in the beetle Onthophagus taurus},
	journal = {Journal of Evolutionary Biology},
	volume = {15},
	year = {2002},
	pages = {784-795},
	abstract = {Theoretical models of paternal care predict that facultative reductions in male care may occur under certain conditions. One important parameter that has been shown to influence the outcome of these models is a male{\textquoteright}s confidence of paternity. In this study, we tested whether the amount of care provided by horned males in the dimorphic beetle, Onthophagus taurus, varied with his confidence of paternity. Male care results in an increased weight of dung provided in the brood masses produced by the pair. Using the sterile male technique we showed that a horned male{\textquoteright}s paternity declined with the number of sneak males in the population. The relationship was nonlinear, with paternity declining most rapidly between a frequency of one and three sneaks, and stabilizing thereafter at about 50\%. A horned male{\textquoteright}s paternity was directly related to the number of copulations with the female, relative to the number of copulations achieved by sneaks. Horned males were shown to reduce their care in relation to their declining paternity. Video analysis demonstrated that reductions in male care occurred through a combination of male desertion and a trade-off between caring and paternity assurance behaviours. The number of fights with sneak males was negatively related to the amount of care provided by a horned male. These results suggest that by gauging his expected paternity through the number of fights with sneaks, a horned male is able to assess his paternity and reduce his investment accordingly. Our data thus provide strong empirical support for the proposed link between paternity and paternal care. },
	keywords = {alternative mating tactics, confidence of paternity, Onthophagus taurus, paternal care},
	author = {Hunt, John and Simmons, Leigh W.}
}
@article {1822,
	title = {A cost of maternal care in the dung beetle Onthophagus taurus?},
	journal = {Journal of Evolutionary Biology},
	volume = {15},
	number = {1},
	year = {2002},
	note = {EnglishArticleJANJ EVOLUTION BIOL},
	pages = {57-64},
	abstract = {Parental care theory assumes that investment in current offspring will trade against future investment. A number of field studies on birds have used clutch size manipulations to demonstrate a survival cost to chick rearing. However, such studies do not account for costs accrued during earlier stages of reproduction because not all aspects of reproductive effort are manipulated by varying the number of nestlings. in this study, we investigate the effect of reproductive effort on female survival in the dung beetle, Onthophagus taurus. By experimentally manipulating mating status and dung availability, we demonstrate that virgin females survive longer than mated females and that the survival of mated females was negatively associated with the number of brood masses produced. Using a novel manipulation of the mating system, we separated the effects of egg production and maternal care on female survival. Previously, we have shown that females provisioning with the assistance of a major male provide relatively less care than unassisted females. However, paternal assistance did not alter the number of brood masses produced and hence the amount of reproductive effort that was allocated to egg production. Therefore, our finding, that female survival was increased when receiving paternal assistance provides, to our knowledge, the first definitive evidence that maternal care reduces female lifespan. These results are of major importance to theoretical models on the evolution of parental care.},
	keywords = {BREEDING BLUE TITS, BROOD-SIZE, CLUTCH-SIZE, drosophila-melanogaster, fluctuating asymmetry, LIFE-HISTORY EVOLUTION, life-history trade-off, Onthophagus taurus, PARENTAL, Parental care, reproductive cost, reproductive effort, SURVIVAL},
	author = {Hunt, J. and Simmons, L. W. and Kotiaho, J. S.}
}
@article {2033,
	title = {Proximate determination of male horn dimorphism in the beetle Onthophagus taurus (Coleoptera: Scarabaeidae)},
	journal = {Journal of Evolutionary Biology},
	volume = {12},
	number = {1},
	year = {1999},
	note = {Jan., 1999ArticleEnglish},
	pages = {27-37},
	abstract = {The existence of discrete phenotypic variation within one sex poses interesting questions regarding how such intrasexual polymorphisms are produced and modified during the course of evolution. Approaching these kinds of questions requires insights into the genetic architecture underlying a polymorphism and an understanding of the proximate mechanisms determining phenotype expression. Here we explore the genetic underpinnings and proximate factors influencing the expression of beetle horns - a dramatic sexually selected trait exhibiting intramale dimorphism in many species. Two relatively discrete male morphs are present in natural populations of the dung beetle Onthophagus taurus (Scarabaeidae, Onthophagini). Males exceeding a critical body size develop a pair of long, curved horns on their heads, while those smaller than this critical body size remain essentially hornless. We present results from laboratory breeding experiments designed to assess the relative importance of inherited and environmental factors as determinants of male morphology. Using father-son regressions, our findings demonstrate that horn length and body size of male progeny are not predicted from paternal morphology. instead, natural variation in an environmental factor, the amount of food available to larvae, determined both the body sizes exhibited by males as adults and the presence or absence of horns. The nonlinear scaling relationship between the body size and horn length of males bred in the laboratory did not differ from the pattern of variation present in natural populations, suggesting that nutritional conditions account for variation in male morphology in natural populations as well. We discuss our results by extending ideas proposed to explain the evolution of conditional expression of alternative phenotypes in physically heterogeneous environments toward incorporating facultative expression of secondary sexual traits. We use this synthesis to begin characterizing the potential origin and subsequent evolution of facultative horn expression in onthophagine beetles.},
	keywords = {allometry-, Animalia-, Animals-, Arthropoda-, Arthropods-, body-size, Coleoptera-: Insecta-, Evolution-and-Adaptation, horn-dimorphism, Insects-, Invertebrata-, Invertebrates-, mor, Onthophagus-taurus [dung-beetle] (Coleoptera-): male-, Population-Studies},
	author = {Moczek, A. P. and Emlen, D. J.}
}
