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are only poorly resolved and there are still lively debates about the status of certain taxa (e.g., Wronski et al., unpublished).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)

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

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

Neumann’s enigmatic gazelle (Gazella erlangeri) Threatened taxon or domesticated gazelle?

One of the most challenging questions in regard to Arabian gazelles is the status of G. erlangeri Neumann, 1906 (Fig. 1). Gazelles currently kept in captivity at King Khalid Wildlife Research Centre in Saudi Arabia and Al Wabra Wildlife Preservation in Qatar (Fig. 2) show the described combination of diagnostic features, and thus, were considered to represent G. erlangeri, even though the exact provenance of these gazelles remains obscure. However, captive ‘G. erlangeri’ may have also originated from eastern Oman and could be therefore assigned to G. muscatensis (Fig. 3). Both taxa are considered ‘extinct in the wild’ by the IUCN Red List. Past conservation efforts have been plagued by confusion about the phylogenetic relationship among various—phenotypically discernable—populations (e.g., G. erlangeri, G. muscatensis), and even the question of species boundaries was far from being certain. This lack of knowledge had a direct impact on conservation measures, especially ex situ breeding programmes, hampering the assignment of captive stocks to potential conservation units

Rigid clumps in the <em>MercuryDPM</em> particle dynamics code

Discrete particle simulations have become the standard in science and industrial applications exploring the properties of particulate systems. Most of such simulations rely on the concept of interacting spherical particles to describe the properties of particulates, although, the correct representation of the nonspherical particle shape is crucial for a number of applications. In this work we describe the implementation of clumps, i.e. assemblies of rigidly connected spherical particles, which can approximate given nonspherical shapes, within the MercuryDPM particle dynamics code. MercuryDPM contact detection algorithm is particularly efficient for polydisperse particle systems, which is essential for multilevel clumps approximating complex surfaces. We employ the existing open-source CLUMP library to generate clump particles. We detail the pre-processing tools providing necessary initial data, as well as the necessary adjustments of the algorithms of contact detection, collision/migration and numerical time integration. The capabilities of our implementation are illustrated for a variety of examples

Dark grey gazelles Gazella (Cetartiodactyla: Bovidae) in Arabia: Threatened species or domestic pet?

True gazelles (genus Gazella) are a prime example of a mammalian group with considerable taxonomic confusion. This includes the descriptions of several dark grey taxa of questionable validity. Here, we examined captive dark grey putative Neumann’s gazelle Gazella erlangeri. Our concerted efforts to retrieve mitochondrial sequence information from old museum specimens of two dark grey gazelles, putative G. erlangeri and putative Muscat gazelle G. muscatensis, were unsuccessful. We did, however, find the mtDNA haplotypes of extant putative G. erlangeri to be nested within the haplotype variation of the Arabian gazelle G. arabica. The observed population genetic divergence between G. arabica and putative G. erlangeri (based on 11 nuclear microsatellites) was driven by genetic impoverishment of putative G. erlangeri. These results, along with morphological signatures of domestication (e.g., reduced brain case size), suggest genetic bottle necks and domestication effects as a consequence of prolonged captive breeding. Three hypotheses are discussed: (a) G. erlangeri and/or G. muscatensis are valid species but are now extinct; (b) one or both taxa represent phenotypic variation within G. arabica and, therefore, are synonyms of G. arabica; and (c) captive stocks, exhibiting the effects of domestication and inbreeding, are the sources for the descriptions of G. erlangeri and G. muscatensis. As concerns the conservation of gazelles, based on current knowledge, we strongly advise against using putative G. erlangeri for any introduction initiative but recommend the continued captive management of putative G. erlangeri

Recovery of Ungulate Populations in Post-Civil War Akagera National Park, Rwanda

Following the 1991–1995 civil war in Rwanda, large parts of Akagera National Park (NP) and the adjacent Mutara Game Reserve were endowed by government to returning war refugees for cattle grazing. In 1997, official degazettement reduced the area covered by these two protected areas by 60% (from 2800 km2 to 1120 km2). This study reports trends in population sizes and densities of ungulates in modern Akagera NP (1120 km2), with a focus on the more common ungulates (impala, topi, zebra, buffalo, waterbuck, and warthog). Data from previous surveys are compared with our 2010–2014 road strip counts using distance sampling. A decline of ungulate populations during the civil war, followed by recovery several years after reduction of the size of the Park, is evident. The ungulate populations show different trends in size in recent years, suggesting that the carrying capacity has been reached for some species

Predator-induced changes of female mating preferences: innate and experiential effects

Background: In many species males face a higher predation risk than females because males display elaborate traits that evolved under sexual selection, which may attract not only females but also predators. Females are, therefore, predicted to avoid such conspicuous males under predation risk. The present study was designed to investigate predator-induced changes of female mating preferences in Atlantic mollies (Poecilia mexicana). Males of this species show a pronounced polymorphism in body size and coloration, and females prefer large, colorful males in the absence of predators. Results: In dichotomous choice tests predator-naïve (lab-reared) females altered their initial preference for larger males in the presence of the cichlid Cichlasoma salvini, a natural predator of P. mexicana, and preferred small males instead. This effect was considerably weaker when females were confronted visually with the non-piscivorous cichlid Vieja bifasciata or the introduced non-piscivorous Nile tilapia (Oreochromis niloticus). In contrast, predator experienced (wild-caught) females did not respond to the same extent to the presence of a predator, most likely due to a learned ability to evaluate their predators' motivation to prey. Conclusions: Our study highlights that (a) predatory fish can have a profound influence on the expression of mating preferences of their prey (thus potentially affecting the strength of sexual selection), and females may alter their mate choice behavior strategically to reduce their own exposure to predators. (b) Prey species can evolve visual predator recognition mechanisms and alter their mate choice only when a natural predator is present. (c) Finally, experiential effects can play an important role, and prey species may learn to evaluate the motivational state of their predators. Keywords: Sexual selection; female choice; non-independent mate choice; predator recognition; Poecilia mexican