Casanovas are liars : behavioral syndromes, sperm competition risk, and the evolution of deceptive male mating behavior in live-bearing fishes [version 2; referees: 2 approved, 1 approved with reservations]

Male reproductive biology can by characterized through competition over mates as well as mate choice. Multiple mating and male mate choice copying, especially in internally fertilizing species, set the stage for increased sperm competition, i.e., sperm of two or more males can compete for fertilization of the female’s ova. In the internally fertilizing fish Poecilia mexicana, males respond to the presence of rivals with reduced expression of mating preferences (audience effect), thereby lowering the risk of by-standing rivals copying their mate choice. Also, males interact initially more with a non-preferred female when observed by a rival, which has been interpreted in previous studies as a strategy to mislead rivals, again reducing sperm competition risk (SCR). Nevertheless, species might differ consistently in their expression of aggressive and reproductive behaviors, possibly due to varying levels of SCR. In the current study, we present a unique data set comprising ten poeciliid species (in two cases including multiple populations) and ask whether species can be characterized through consistent differences in the expression of aggression, sexual activity and changes in mate choice under increased SCR. We found consistent species-specific differences in aggressive behavior, sexual activity as well as in the level of misleading behavior, while decreased preference expression under increased SCR was a general feature of all but one species examined. Furthermore, mean sexual activity correlated positively with the occurrence of potentially misleading behavior. An alternative explanation for audience effects would be that males attempt to avoid aggressive encounters, which would predict stronger audience effects in more aggressive species. We demonstrate a positive correlation between mean aggressiveness and sexual activity (suggesting a hormonal link as a mechanistic explanation), but did not detect a correlation between aggressiveness and audience effects. Suites of correlated behavioral tendencies are termed behavioral syndromes, and our present study provides correlational evidence for the evolutionary significance of SCR in shaping a behavioral syndrome at the species level across poeciliid taxa

Discrete dynamics by different concepts of majorization

For the description of complex dynamics of open systems an approach is given by different concepts of majorization (order structure). Discrete diffusion processes with both invariant object number and sink or source can be represented by the development of Young diagrams on lattices. As experimental example we investigated foam decay, dominated by sinks. The relevance of order structures for characterization of certain processes is discussed

The Taxonomy and Phylogeography of two Arabian gazelles

The phylogeny of the Arabian gazelles is generally not well understood (e.g., Groves 1996). Morphological traits were commonly used as a basis for classification leading to frequent misclassifications. Sister group relationships within the genus are only poorly resolved and there are still lively debates about the status of certain taxa (e.g., Wronski et al., unpublished). The aim of this project is to characterize several Arabian, African and Asian gazelle species using molecular tools while including several taxonomically unclear “species”

Endemic Farasan gazelle (Gazella gazella farasani) enhance the dispersal of invasive Prosopis juliflora on Farasan Islands, Saudi Arabia

Invasive Prosopis juliflora dispersal on Farasan Kebir (Miharraq area, Wadi Matr) was investigated in relation to endozoochory by Farasan Gazelle (Gazella gazella farasani). A germination experiment was conducted to test defecated seed viability of competing P. juliflora and Acacia ehrenbergiana. It revealed that 0.0013 ± 0.0009 Acacia seeds per gram of faeces germinated, while the rate of germinating Prosopis seeds was higher (0.0053 ± 0.0022 seeds per gram of faeces). Dung middens with a Prosopis seedling (or a young tree nearby) were distinctly closer to the putative centre of Prosopis introduction (Al-Qisar and Miharraq villages) than middens without Prosopis, suggesting that gazelles whose home ranges (mean size, females: 2.07 km2, males: 0.71 km2) encompass the gardens edging the aforementioned villages contribute to the dispersal of this invasive species. Altogether, our results suggest that gazelles on the Farasan Islands contribute to the invasion success of Prosopis; it still needs to be investigated though to what extent also domestic livestock - in particular goats - contribute to Prosopis dispersal. Based on our present data it is recommended to reduce the number of Prosopis trees in the protected area around Wadi Matr by mechanical eliminatio

Let‘s talk about… different things! Communication within and among sexes in Farasan gazelles

Scent marking in localized defecation sites (latrines) has often been interpreted in the context of male territory defense. Still, latrines could have different functions in both sexes, especially where territorial males monopolize groups of females with stable social alliances. We assessed the spatial distribution of latrines within home ranges of wild ranging Arabian gazelles (Gazella arabica) on Farasan Island (Red Sea, Saudi Arabia)

Phylogenetic and phylogeographic analyses of African and Arabian Dorcas gazelles (Gazella dorcas)

Once common throughout the entire Sahelo-Saharan region, population sizes of Dorcas gazelles (Gazella dorcas) are nowadays decreasing dramatically. The uncertain taxonomy of this species—with a variety of described subspecies without validated status—hampers conservation efforts. In this situation, phylogenetic and phylogeographic investigations using molecular techniques are highly warranted conservation tools. Here, we investigate sequence variation of the mitochondrial cytochrome b gene and control region of 73 dorcas (G. dorcas) and Saudi gazelles (G. saudiya) throughout the entire distribution range

Sexual harassment in live-bearing fishes (Poeciliidae): comparing courting and noncourting species

Sexual harassment by males has been reported from several live-bearing fishes (Poeciliidae) and has been shown to inflict costs on females. For example, poeciliid females have reduced feeding opportunities when accompanied by a male because females dedicate attention to avoiding male copulation attempts. Poeciliid species differ considerably in male mating behavior, such as the presence or absence of courtship. Courting males display in front of the females, but males attempting to sneak-copulate approach females from behind, that is, in the blind portion of their visual field, and force copulations, which can be viewed as a male persistence trait. We predicted that poeciliid females need to be more vigilant in the presence of noncourting males, and costs of harassment by noncourting males might be stronger. In a comparative approach we examined the costs of male sexual harassment for females as reduced feeding time in 9 species of live-bearing fishes, including courting (Poecilia latipinna, Poecilia reticulata, Xiphophorus cortezi, Xiphophorus variatus) and noncourting species (Poecilia mexicana [surface- and cave-dwelling form], Poecilia orri, Gambusia affinis, Gambusia geiseri, Heterandria formosa). In all species examined except for the cave form of P. mexicana, focal females spent significantly less time feeding in the presence of a male than when together with another female. The time females spent feeding was found to significantly decline with increasing male mating activity (sum of all sexual behaviors), but there was no support for the idea that females would spend more time feeding in the presence of courting males compared with noncourting one

A new and morphologically distinct population of cavernicolous Poecilia mexicana (Poeciliidae: Teleostei)

The cave molly, Poecilia mexicana, from the Cueva del Azufre, a sulfur cave in Tabasco, Mexico, ranks among the best-studied cave fishes worldwide, despite being known from a single population only. Here we describe a newly discovered second population of cave-dwelling P. mexicana from a nearby, but mostly non-sulfidic cave (Luna Azufre). Despite apparent similarities between the two populations (such as reduced eye diameter and reduced pigmentation), a geometric morphometric analysis revealed pronounced morphological differentiation between the two cave form

Age-dependent mating tactics in male bushbuck (Tragelaphus scriptus)

Intra-specific variation in mating behaviour has been described for a number of taxa including arthropods, fishes, amphibians, reptiles, birds and mammals. Several mechanisms have been proposed to explain the various mating behavioural variations observed in mammals. For example, an individual’s behaviour may be constrained by its condition or status (making-the- best of-a-bad-job strategy) or an alternative phenotype may be maintained by frequency-dependent selection influencing a genetic polymorphism (alternative strategies). In the majority of ungulates, variation in mating tactics is most likely maintained as a conditional strategy influenced by multiple internal factors like age, health or body size, as well as external factors such as population density, number of competitors and social dominance rank. In the present study, we investigated male mating tactics in a cryptic, bush-dwelling antelope from tropical Africa, the bushbuck, Tragelaphus scriptus (Figures.1, 2). Different mating strategies are expected to emerge, if variation in mating tactic is maintained as a conditional strategy influenced by age and / or body size: 1) Defending a territory when old and strong, what allows the owner to associating more frequently with females within the combined territory and home-range area. 2) No territory defence when young and weak, thereby associating with females less frequently and therefore sneak-mating with them