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As clear as mud: Turbidity induces behavioral changes in the African cichlid Pseudocrenilabrus multicolor
Suzanne M. GRAY, Laura H. McDONNELL, Fabio G. CINQUEMANI,Lauren J. CHAPMAN
Current Zoology , 2012,
Abstract: Aquatic biodiversity is being lost at an unprecedented rate. One factor driving this loss is increased turbidity, an environmental stressor that can impose behavioral, morphological, and/or physiological costs on fishes. Here we describe the behavioral response of a widespread African cichlid, Pseudocrenilabrus multicolor victoriae, to turbidity. We used a split-brood rearing design to test if F1 offspring reared in turbid water, originating from river (turbid) and swamp (clear) populations, behave differently than full-sibs reared in clear water. We examined two facets of behavior: (1) behaviors of fish in full sib groups, including activity level and social dynamics collected during the rearing period; and (2) male aggressive behavior directed at potential male competitors after fish had reached maturity; this was done in an experimental set-up independent of the rearing aquaria. Regardless of population of origin, fish reared in turbid water were marginally less active and performed fewer social behaviors than those reared in clear water. On the other hand, when tested against a competitor in turbid water, males performed more aggressive behaviors, regardless of population of origin or rearing environment. Our results suggest a plastic behavioral response to turbidity that may allow P. multicolor to persist over a range of turbidity levels in nature by decreasing activity and general social behaviors and intensifying reproductive behaviors to ensure reproductive success [Current Zoology 58 (1): 146–157, 2012].
Evolution and maintenance of sexual size dimorphism: aligning phylogenetic and experimental evidence
Matja？ Kuntner,Mark A. Elgar
Frontiers in Ecology and Evolution , 2014, DOI: 10.3389/fevo.2014.00026
Abstract: Integrating the insights derived from both phylogenetic and experimental approaches offers a more complete understanding of evolutionary patterns and processes, yet it is rarely a feature of investigations of the evolutionary significance of trait variation. We combine these approaches to reinterpret the patterns and processes in the evolution of female biased sexual size dimorphism in Nephilidae, a spider lineage characterized by the most extreme sexual size dimorphism among terrestrial animals. We use a molecular phylogeny to reconstruct the size evolution for each sex and reveal a case of “sexually dimorphic gigantism”: both sexes steadily outgrow their ancestral sizes, but the female and male slopes differ, and hence sexual size dimorphism steadily increases. A review of the experimental evidence reveals a predominant net selection for large size in both sexes, consistent with the phylogenetic pattern for females but not for males. Thus, while sexual size dimorphism in spiders most likely originates and is maintained by fecundity selection on females, it is unclear what selection pressures prevent males from becoming as large as females. This integrated approach highlights the dangers of inferring evolutionary significance from experimental studies that isolate the effects of single selection pressures.
The dynamics of male-male competition in Cardiocondyla obscurior ants
Sylvia Cremer, Masaki Suefuji, Alexandra Schrempf, Juergen Heinze
BMC Ecology , 2012, DOI: 10.1186/1472-6785-12-7
Abstract: We found that old ergatoid males consistently won fights against ergatoid males younger than two days. Old males did not differentiate between different types of unpigmented pupae several days before emergence, but had more frequent contact to ready-to-eclose pupae of female sexuals and winged males than of workers and ergatoid males. In rare cases, old ergatoid males displayed alleviated biting of pigmented ergatoid male pupae shortly before adult eclosion, as well as copulation attempts to dark pupae of female sexuals and winged males. Ergatoid male behaviour may be promoted by a closer similarity of the chemical profile of ready-to-eclose pupae to the profile of adults than that of young pupae several days prior to emergence.Young ergatoid males of C. obscurior would benefit greatly by hiding their identity from older, resident males, as they are highly vulnerable during the first two days of their adult lives. In contrast to the winged males of the same species, which are able to prevent ergatoid male attacks by chemical female mimicry, young ergatoids do not seem to be able to produce a protective chemical profile. Conflicts in male-male competition between ergatoid males of different age thus seem to be resolved in favour of the older males. This might represent selection at the colony level rather than the individual level.
Limb amputation by male Neotropical longhorn beetles during competition for females
Larsson, Folke Kustvall;
Biota Neotropica , 2010, DOI: 10.1590/S1676-06032010000100030
Abstract: the biology and mating behaviour of the spectacularly large and brightly coloured neotropical longhorn beetle schwarzerion holochlorum bates 1872 (coleoptera: cerambycidae) is largely unknown. for the first time i report and photographically document violent male-male competitions for females involving frequent amputations of competitors' legs and antennae.
Anting behavior by the White-bearded Manakin (Manacus manacus, Pipridae): an example of functional interaction in a frugivorous lekking bird
Cestari, César;
Biota Neotropica , 2010, DOI: 10.1590/S1676-06032010000400038
Abstract: behavioral studies of birds have reported several functions for active anting. maintenance of plumage and prevention from ectoparasites are some examples. in this context, anting by males may be of particular importance in a classical lek mating system, where male-male competition is common and individuals with higher fitness may be more successful at attracting of females. in the present note, i describe the anting behavior of white-bearded manakin (manacus manacus) and i relate it to lek breeding and feeding (frugivory) habits of the species. males used up to seven solenopsis sp. ants. they rubbed each small ant from 4 to 31 times on undertail feathers until the ants were degraded; ants were not eaten. males then searched for a new ant in the court. seeds discarded by males on their individual display courts attract herbivorous ants that are used for anting as a way to maintain feathers and fitness. i hypothesize that anting in white-bearded manakin may increase the probability of males to attract females to their display courts.
The role of male contest competition over mates in speciation
Anna QVARNSTR？M, Niclas VALLIN, Andreas RUDH
Current Zoology , 2012,
Abstract: Research on the role of sexual selection in the speciation process largely focuses on the diversifying role of mate choice. In particular, much attention has been drawn to the fact that population divergence in mate choice and in the male traits subject to choice directly can lead to assortative mating. However, male contest competition over mates also constitutes an important mechanism of sexual selection. We review recent empirical studies and argue that sexual selection through male contest competition can affect speciation in ways other than mate choice. For example, biases in aggression towards similar competitors can lead to disruptive and negative frequency-dependent selection on the traits used in contest competition in a similar way as competition for other types of limited resources. Moreover, male contest abilities often trade-off against other abilities such as parasite resistance, protection against predators and general stress tolerance. Populations experiencing different ecological conditions should therefore quickly diverge non-randomly in a number of traits including male contest abilities. In resource based breeding systems, a feedback loop between competitive ability and habitat use may lead to further population divergence. We discuss how population divergence in traits used in male contest competition can lead to the build up of reproductive isolation through a number of different pathways. Our main conclusion is that the role of male contest competition in speciation remains largely scientifically unexplored [Current Zoology 58 (3): 490–506, 2012].
Notes on the biology of the unidentified invasive harvestman Leiobunum sp. (Arachnida: Opiliones)
Wijnhoven, Hay
Arachnologische Mitteilungen , 2011, DOI: 10.5431/aramit4103
Abstract: Since about the year 2000 an unidentified, introduced harvestman of the genus Leiobunum has been rapidly invading Europe. The published records are from the Netherlands, Germany, Austria and Switzerland. A population of Leiobunum sp. in the Netherlands was studied frequently during the day and night. Its life cycle, hunting strategy, diet and accompanying harvestman species were recorded, and mating, male-male fights and ovipositing behaviour studied, as well as the spider species preying on this Leiobunum species. Food items were collected, indicating that its food consists of a wide range of live as well as dead invertebrates including spent spider prey scavenged for at ground level. Vegetable matter like berries, as well as bird droppings were also consumed. The mating strategy is very complex. A male guards an egg depositing female and he defends her against other advancing males, resulting in male-male fights. The guarding male frequently mates. Also courtship behaviour has been observed, including nuptial feeding with a fluid, probably originating from the accessory penal glands and delivered by the male into the female’s stomotheca via sacs located on the distal part of the penis truncus. Eggs are deposited in holes and crevices of walls.
Detection of Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyticum by Multiplex PCR in Semen Sample of Infertile Men
M Golshani,G Eslami,Sh Mohhammadzadeh Ghobadloo,F Fallah
Iranian Journal of Public Health , 2007,
Abstract: Background: The aim of this study was to detect Chlamydia trachomatis, Mycoplasma hominis and Ureaplasma urealyti cum from semen samples of infertile men by Multiplex PCR and investigation of influence of bacteriospermia on semen parame ters. Methods: Semen samples of 200 infertile men were evaluated by Multiplex PCR. In addition, analysis of semen parameters was performed according to the WHO guidelines. Results: All the patients were without clinical symptoms of urogenital tract infection. Thirty three percent of cases showed at least one bacterium. We found a noticeable relation between the presence of bacteriospermia and the rate of non motile and morphologically abnormal sperms (P 0.05). Conclusion: Asymptomatic existence of Chlamydia and Mycoplasmas in urogenital tracts might play an important role in sperm impairment due to infertility. Bacteriospermia can influence sperm's motility, morphology and concentration.
Re-emergence of the leaf clip gesture during an alpha takeover affects variation in male chimpanzee loud calls
Ammie K. Kalan,Christophe Boesch
- , 2018, DOI: 10.7717/peerj.5079
Abstract: Loud calls are used by many species as long-distance signals for group defense, mate attraction, and inter- and intragroup spacing. Chimpanzee loud calls, or pant hoots, are used in a variety of contexts including group coordination and during male contests. Here, we observed an alpha male takeover in wild chimpanzees (Pan troglodytes verus) during which the leaf clipping gesture re-emerged after disappearing for almost two years in this community. Leaf clipping only occurred in males and was observed almost exclusively prior to pant hoot vocalizations, as has been observed in other chimpanzee communities of the Ta？ forest in C？te d’Ivoire. Consequently, we hypothesized that leaf clipping may be important for male-male competition by affecting variation in the acoustic properties of male chimpanzee loud calls. We therefore investigated whether pant hoots preceded by leaf clipping differed acoustically from those without, while also testing the influence of social context on pant hoot variation, namely male dominance rank and hierarchy instability, i.e., before, during and after the alpha takeover. We found that pant hoots preceded by leaf clipping were longer, contained more call elements and drum beats, and lower fundamental and peak frequencies. Moreover, during the alpha takeover pant hoots were shorter, contained fewer drum beats and higher fundamental frequencies. Additionally, pant hoot and aggression rates were also highest during the alpha takeover with leaf clipping more likely to occur on days when pant hooting rates were high. Overall social rank had limited effects on pant hoot variation. We suggest that elevated arousal and aggression during the alpha takeover triggered the re-emergence of leaf clipping and the associated acoustic changes in pant hoots. Further research should focus on the potential mechanisms by which leaf clipping is connected to variation in pant hoots and cross-population comparisons of the behaviour
Microsatellite Markers for the Chameleon Grasshopper (Kosciuscola tristis) (Orthoptera: Acrididae), an Australian Alpine Specialist
Kate D. L. Umbers,Siobhan Dennison,Czarina A. Manahan,Laurence Blondin,Christine Pagés,Ange-Marie Risterucci,Marie-Pierre Chapuis
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms130912094
Abstract: A set of polymorphic loci was characterised using an enrichment library for the Australian alpine specialist, the chameleon grasshopper ( Kosciuscola tristis), an atypical grasshopper known for its remarkable temperature-controlled colour change. The number of alleles per locus ranged from three to 20 and observed heterozygosity from 0.16 to 0.76. These are the first microsatellite markers for a non-endangered Australian alpine animal and will inform questions of gene flow across the sky islands of this unique and threatened region.
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