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1.
Saudi J Biol Sci ; 28(9): 5034-5041, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34466079

RESUMO

Many factors affect the habitat selection for animal species, which in turn may greatly affect their distribution in different ecosystems. Understanding the processes that affect habitat selection is also critical for guiding and managing conservation initiatives. Our study aimed to assess the habitat selection by free-ranging Spiny-tailed lizard (Uromastyx aegyptia) by analyzing a geospatial data connecting its burrow parameters to different habitat characteristics within selected sites in Hail region, Saudi Arabia. We examined evidence and patterns of significant spatial clustering for (366) active burrows by linking their parameters (burrow entrance size, burrow entrance width and burrow entrance height), their reference geographical locations and, two habitat characteristics defined by soil type and vegetation cover. The objective of the analysis was to increase the understanding on the burrows aggregation process in the space and, to describe its possible relation to other spatial habitat configurations. Analysis of distances based on the Nearest Neighbor Index (NNI) and hotspots detection in Nearest neighbor hierarchical clustering (Nnh) suggested twelve (12) spatial clusters located within the study area. In addition, a spatial ordinary least square (OLS) and Poisson regression models revealed significant effects of soil type and vegetation cover on burrow parameters (OLS, p < 0.05; Poisson, p < 0.001), which indicate a strong association between burrows parameters and habitats characteristics. Findings from the study also suggest that other factors such as elevations, highways, and human settlement concentration spots could possibly play a major role in defining burrow spatial aggregation and furthermore have a significant impact on habitat selection.

2.
Saudi J Biol Sci ; 28(1): 587-591, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424344

RESUMO

The Bar-tailed Lark (Ammomanes cinctura) breeds in desert and semi-desert areas of the Saharo-Sindian region, from north-west Africa through the arid plains of the Arabian Peninsula to the Sind. Despite having a wide distribution, little information is available on the breeding ecology of this species. This study was conducted in a desert in the north of Saudi Arabia, where the daytime ambient temperature may exceed 40 °C. In contrast, the night ambient temperature may reach less than 10 °C in late spring and early summer. The objectives of this study were to collect some baseline data on some aspects of the breeding ecology of this species and to record the nest attendance behavior. The study found that Bar-tailed Larks preferred to nest under shrub trunks, which may camouflage both nests and incubating parents against predators and protect eggs, nestlings and incubating parents from hostile weather conditions. Moreover, nest attendance was high, as Bar-tailed Lark parents incubated their eggs 95.97 ± 2.62% over the entire day, and they seemed to maintain the eggs at temperatures around 23-33 °C. In addition, they incubated more at night than during the daytime. Temperatures under the shrubs at night fell below 21 °C, thus parents increased the nest attendance to warm the eggs and prevent the embryos from exposure to lethal temperatures.

3.
Saudi J Biol Sci ; 27(9): 2238-2244, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32884404

RESUMO

The House mice (Mus musculus Linnaeus, 1758), play an important role in the transmission of diseases, both in humans and livestock, through ectoparasite carried on their feces, urine and hair remnants. The purpose of this study was to investigate the ectoparasites infestation, as well as their quantitative and qualitative abundance and, prevalence in the house mice captured from Hai'l region, Kingdom of Saudi Arabia (KSA). Parasitological investigations were performed on 70 house mice trapped during 2012-2013 from two localities (Hai'l City residential area and Al-Khitah agricultural farm habitats in Hai'l region). Captured mice were identified as males (34.3% and 48.6%) and females (65.7% and 51.4%) from the residential and agricultural farm habitats, respectively. The findings of the study showed that the sex ratio of the mice found in different habitats did not influence the level of ectoparasite infestation (P > 0.05). Therefore, we combined only sex-wise samples for each habitat and isolated habitats treated separately for our subsequent analyses. A total of 514 ectoparasites individuals belong to four species were recovered from the mice, which included 339 of flea (Xenopsylla cheopis Rothschild, 1903), 39 of sucking lice (Polyplax spinulosa Burmeister, 1835), 37 of sucking lice Polyplax serrata Burmeister, 1839), and 99 of mite species (Laelaps echidninus Berlese, 1887). The presence of zoonotic parasites indicates that Mus musculus as a reservoir, might represent a danger to the public health particularly in the two sampled areas. Results also suggest an increasingly need for further studies to assess the role of the ectoparasites of house mice and their possible involvment in transmission of diseases among these areas.

4.
PLoS One ; 8(4): e60998, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23613768

RESUMO

Social behaviours are highly variable between species, populations and individuals. However, it is contentious whether behavioural variations are primarily moulded by the environment, caused by genetic differences, or a combination of both. Here we establish that biparental care, a complex social behaviour that involves rearing of young by both parents, differs between closely related populations, and then test two potential sources of variation in parental behaviour between populations: ambient environment and genetic differentiation. We use 2904 hours behavioural data from 10 geographically distinct Kentish (Charadrius alexandrinus) and snowy plover (C. nivosus) populations in America, Europe, the Middle East and North Africa to test these two sources of behavioural variation. We show that local ambient temperature has a significant influence on parental care: with extreme heat (above 40 °C) total incubation (i.e. % of time the male or female incubated the nest) increased, and female share (% female share of incubation) decreased. By contrast, neither genetic differences between populations, nor geographic distances predicted total incubation or female's share of incubation. These results suggest that the local environment has a stronger influence on a social behaviour than genetic differentiation, at least between populations of closely related species.


Assuntos
Charadriiformes/genética , Meio Ambiente , Variação Genética , Comportamento de Nidação , Animais , Cruzamento , Feminino , Estágios do Ciclo de Vida/genética , Masculino
5.
Mol Ecol ; 21(23): 5864-79, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23094674

RESUMO

Gene flow promotes genetic homogeneity of species in time and space. Gene flow can be modulated by sex-biased dispersal that links population genetics to mating systems. We investigated the phylogeography of the widely distributed Kentish plover Charadrius alexandrinus. This small shorebird has a large breeding range spanning from Western Europe to Japan and exhibits an unusually flexible mating system with high female breeding dispersal. We analysed genetic structure and gene flow using a 427-bp fragment of the mitochondrial (mtDNA) control region, 21 autosomal microsatellite markers and a Z microsatellite marker in 397 unrelated individuals from 21 locations. We found no structure or isolation-by-distance over the continental range. However, island populations had low genetic diversity and were moderately differentiated from mainland locations. Genetic differentiation based on autosomal markers was positively correlated with distance between mainland and each island. Comparisons of uniparentally and biparentally inherited markers were consistent with female-biased gene flow. Maternally inherited mtDNA was less structured, whereas the Z-chromosomal marker was more structured than autosomal microsatellites. Adult males were more related than females within genetic clusters. Taken together, our results suggest a prominent role for polyandrous females in maintaining genetic homogeneity across large geographic distances.


Assuntos
Charadriiformes/genética , Fluxo Gênico , Variação Genética , Comportamento Sexual Animal , Migração Animal , Animais , DNA Mitocondrial , Feminino , Genética Populacional , Masculino , Repetições de Microssatélites , Filogenia , Cromossomos Sexuais
6.
Saudi J Biol Sci ; 19(3): 311-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23961191

RESUMO

One of the expected effects of the global warming is changing coastal habitats by accelerating the rate of sea level rise. Coastal habitats support large number of marine and wetland species including shorebirds (plovers, sandpipers and allies). In this study, we investigate how coastal habitats may be impacted by sea level rise in the Farasan Islands, Kingdom of Saudi Arabia. We use Kentish plover Charadrius alexandrinus - a common coastal breeding shorebird - as an ecological model species to predict the influence of sea level rise. We found that any rise of sea level is likely to inundate 11% of Kentish plover nests. In addition, 5% of the coastal areas of Farasan Islands, which support 26% of Kentish plover nests, will be flooded, if sea level rises by one metre. Our results are constrained by the availability of data on both elevation and bird populations. Therefore, we recommend follow-up studies to model the impacts of sea level rise using different elevation scenarios, and the establishment of a monitoring programme for breeding shorebirds and seabirds in Farasan Islands to assess the impact of climate change on their populations.

7.
PLoS One ; 6(11): e26995, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22096515

RESUMO

Understanding and resolving conflicts between phenotypic and genetic differentiation is central to evolutionary research. While phenotypically monomorphic species may exhibit deep genetic divergences, some morphologically distinct taxa lack notable genetic differentiation. Here we conduct a molecular investigation of an enigmatic shorebird with a convoluted taxonomic history, the White-faced Plover (Charadrius alexandrinus dealbatus), widely regarded as a subspecies of the Kentish Plover (C. alexandrinus). Described as distinct in 1863, its name was consistently misapplied in subsequent decades until taxonomic clarification ensued in 2008. Using a recently proposed test of species delimitation, we reconfirm the phenotypic distinctness of dealbatus. We then compare three mitochondrial and seven nuclear DNA markers among 278 samples of dealbatus and alexandrinus from across their breeding range and four other closely related plovers. We fail to find any population genetic differentiation between dealbatus and alexandrinus, whereas the other species are deeply diverged at the study loci. Kentish Plovers join a small but growing list of species for which low levels of genetic differentiation are accompanied by the presence of strong phenotypic divergence, suggesting that diagnostic phenotypic characters may be encoded by few genes that are difficult to detect. Alternatively, gene expression differences may be crucial in producing different phenotypes whereas neutral differentiation may be lagging behind.


Assuntos
Evolução Biológica , Aves/genética , Animais , Aves/classificação , Genética Populacional , Fenótipo
8.
Front Zool ; 7: 1, 2010 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-20148101

RESUMO

BACKGROUND: Parental care often increases offspring survival, but is costly to the parents. A trade-off between the cost and benefit of care is expected, so that when care provisioning by both parents is essential for the success of young, for instance in extremely cold or hot environments, the parents should rear their young together. We investigated the latter hypothesis in a ground nesting shorebird, the Kentish plover Charadrius alexandrinus in an extremely hot environment, the Arabian Desert. Midday ground temperature was often above 50 degrees C in our study site in Abu Dhabi (United Arab Emirates), thus leaving the eggs unattended even for a few minute risks overheating and death of embryos. RESULTS: Through the use of video surveillance systems we recorded incubation routines of male and female Kentish plovers at 28 nests over a full day (24 h). We show that ambient temperature had a significant influence on incubation behaviour of both sexes, and the relationships are often non-linear. Coordinated incubation between parents was particularly strong in midday with incubation shared approximately equally between the male and the female. The enhanced biparental incubation was due to males increasing their nest attendance with ambient temperature. CONCLUSIONS: Our results suggest biparental care is essential during incubation in the Kentish plover in extremely hot environments. Shared incubation may also help the parents to cope with heat stress themselves: they can relieve each other frequently from incubation duties. We suggest that once the eggs have hatched the risks associated with hot temperature are reduced: the chicks become mobile, and they gradually develop thermoregulation. When biparental care of young is no longer essential one parent may desert the family. The relaxed demand of the offspring may contribute to the diverse breeding systems exhibited by many shorebirds.

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