scholarly journals Feeding ecology and sexual dimorphism in a speciose flower beetle clade (Hopliini: Scarabaeidae)

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4632 ◽  
Author(s):  
Jonathan F. Colville ◽  
Mike D. Picker ◽  
Richard M. Cowling
Keyword(s):  
Sexual Selection ◽  
Sexual Dimorphism ◽  
South African ◽  
Feeding Ecology ◽  
Scoring System ◽  
Feeding Guilds ◽  
Feeding Guild ◽  
Visual Signalling ◽  
Almost All ◽  
Feeding Resources

The relationship between feeding ecology and sexual dimorphism is examined in a speciose South African monkey beetle clade. We test whether feeding and mating at a fixed site (embedding guild) is associated with greater levels of sexual dimorphism and possibly sexual selection than species using unpredictable feeding resources (non-embedding guild). Sexual dimorphism was measured using a point scoring system for hind leg and colour across the two feeding guilds for >50% of the regional fauna. Quantification of hind leg dimorphism using a scoring system and allometric scaling were used to identify traits subject to sexual selection. Feeding guild had a significant effect on hind leg dimorphism, with embedders having high and non-embedders low scores. The sessile and defendable distribution of females on stable platform flowers may favour contests and associated hind leg weaponry. In contrast, degree of colour dimorphism between the sexes was not associated with any particular feeding guild, and may serve to reduce male conflict and combat. Embedder males had high proportions (∼76%) of species with positive allometric slopes for almost all hind leg traits. For male non-embedders, only ∼37% of species showed positive scaling relationships. Phylogenetic data, in conjunction with behavioural data on the function of leg weaponry and visual signalling among males is needed to better understand the link between sexual dimorphism and sexual selection in the radiation of the monkey beetles.

scholarly journals The impact of Sosnowsky’s Hogweed on feeding guilds of birds

2021 ◽  
Author(s):  
Emilia Grzędzicka ◽  
Jiří Reif
Keyword(s):  
Negative Impact ◽  
Bird Community ◽  
Plant Invasions ◽  
Bird Communities ◽  
Feeding Guilds ◽  
Guild Structure ◽  
Feeding Guild ◽  
Potential Impact ◽  
Underlying Mechanisms ◽  
The Impact

AbstractPlant invasions alter bird community composition worldwide, but the underlying mechanisms still require exploration. The investigation of feeding guild structure of bird communities can be informative in respect to the potential impact of invasion features on the availability of food for birds. For this purpose, we focused on determining the influence of the invasive Sosnowsky’s Hogweed Heracleum sosnowskyi on the abundance of birds from various feeding guilds. In spring and summer 2019, birds were counted three times on 52 pairs of sites (control + Heracleum) in southern Poland, at various stages of Sosnowsky’s Hogweed development (i.e. sprouting, full growth and flowering, all corresponding to respective bird counts). We have shown that the presence of invader negatively affected the abundance of birds from all feeding guilds. However, a closer examination of the invaded sites uncovered that responses of particular guilds differed in respect to development stages expressed by a set of characteristics of the invader. Ground and herb insectivores were more common on plots with a higher number of the invader, while the abundance of bush and tree insectivores was negatively correlated with hogweeds’ height. Granivores were not affected by the invader’s features, while the abundance of omnivores was negatively related to the number of flowering hogweeds. Besides showing the general negative impact of the invader on different feeding guilds, our research has shown that certain aspects of Sosnowsky’s Hogweed invasion may support or depress occurrence of different birds on invaded plots. Knowledge of these aspects may facilitate our capacity for coping with challenges the invasive plants put in front of bird conservationists.

scholarly journals Development of a clinical feeding assessment scale for very young infants in South Africa

2016 ◽  
Vol 63 (1) ◽  
Author(s):  
Mari Viviers ◽  
Alta Kritzinger ◽  
Bart Vinck
Keyword(s):  
South Africa ◽  
High Risk ◽  
South African ◽  
Delphi Method ◽  
Scoring System ◽  
Oropharyngeal Dysphagia ◽  
Assessment Instrument ◽  
Assessment Scale ◽  
Young Infants ◽  
Feeding Assessment

Background: There is a need for validated neonatal feeding assessment instruments in South Africa. A locally developed instrument may contribute to standardised evaluation procedures of high-risk neonates and address needs in resource constrained developing settings.Objective: The aim of the study was to develop and validate the content of a clinical feeding assessment scale to diagnose oropharyngeal dysphagia (OPD) in neonates.Method: The Neonatal Feeding Assessment Scale (NFAS) was developed using the Delphi method. Five international and South African speech-language therapists (SLTs) formed the expert panel, participating in two rounds of electronic questionnaires to develop and validate the content of the NFAS.Results: All participants agreed on the need for the development of a valid clinical feeding assessment instrument to use with the neonatal population. The initial NFAS consisted of 240 items across 8 sections, and after the Delphi process was implemented, the final format was reduced to 211 items across 6 sections. The final format of the NFAS is scored using a binary scoring system guiding the clinician to diagnose the presence or absence of OPD. All members agreed on the format, the scoring system and the feeding constructs addressed in the revised final format of the NFAS.Conclusion: The Delphi method and the diverse clinical and research experience of participants could be integrated to develop the NFAS which may be used in clinical practice in South Africa or similar developing contexts. Because of demographically different work settings marked by developed versus developing contexts, participants did not have the same expectations of a clinical dysphagia assessment. The international participants contributed to evidence-based content development. Local participants considered the contextual challenges of South African SLTs entering the field with basic competencies in neonatal dysphagia management, thereby justifying a comprehensive clinical instrument. The NFAS is aimed at clinicians working in Neonatal Intensive Care Units where they manage large caseloads of high-risk neonates. Further validation of the NFAS is recommended to determine its criterion validity in comparison with a widely accepted standard such as the modified barium swallow study.

Effective Planning for Rural Development in A Democratic South Africa: The Prospects of Rural Cooperatives

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
France Khutso Lavhelani Kgobe
Keyword(s):  
South Africa ◽  
Rural Development ◽  
South African ◽  
Rural Areas ◽  
Social Capital Theory ◽  
Capital Theory ◽  
Rural Cooperatives ◽  
The Government ◽  
Almost All ◽  
Effective Planning

This paper explores the potency of rural cooperatives for the effective planning and implementation of rural strategies to address poverty. Rural cooperatives function as a participatory approach that provides the potential to equip and empower people in rural areas with various skills. Hence, rural cooperatives represent the means and strategies to unshackle rural people from the vicious circle of poverty. The contestation about a deadlock of rural development has become pertinent in the recent and ongoing political transformation in South Africa. This paper is grounded on the social capital theory and its ideals. As such, it depends on a literature review for its premise, argument, crux and purpose, as well as drawing up results and conclusions. The paper gathers information in respect of various scholars’ notions on rural cooperatives and rural development from related articles, journals and books. The paper reveals that where the South African government is confronted and characterised by some form of upheaval and service delivery challenges, so rural cooperatives are fit to capacitate citizens to avoid depending on the government for scarce resources. The paper further reveals that rural cooperatives are deemed to ameliorate the long-standing patterns of developmental backlogs in almost all South African municipalities. The conclusion that can be made from this paper is that the authentic promotion of rural development in the formulation of a well-informed legislative framework, that is clear and unambiguous, can deal effectively with the challenges of rural cooperatives.

scholarly journals Effect of Farming and Rainfall on the Species Diversity, Population Density and Community Structure of Birds Breeding in the Kalahari Woodland, NE Namibia

Zoodiversity ◽  
2021 ◽  
Vol 55 (6) ◽  
pp. 451-458
Author(s):  
G. Kopij
Keyword(s):  
Community Structure ◽  
Species Diversity ◽  
Bird Species ◽  
Diversity Indices ◽  
Annual Rainfall ◽  
Feeding Guilds ◽  
Line Transect ◽  
Population Densities ◽  
Feeding Guild ◽  
Turtle Dove

The line transect method has been employed to assess species diversity, population densities and community structure of birds breeding in a mosaic of Kalahari Woodland and farmland, NE Namibia. The transect, 4.5 km long, was surveyed in 2014 and 2015. The total annual rainfall in 2014 was much higher than in 2015 (427 mm vs. 262 mm). In total, 40 breeding species in 2014, and 46 in 2015 were recorded. Six species were dominant in 2014 (Cape Turtle Dove, Laughing Dove, Emerald-spotted Dove, Blue Waxbill, and White-browed Scrub Robin) and only three species in 2015 (Cape Turtle Dove and Blue Waxbill and Yellow-fronted Canary). Although the cumulative dominance in 2014 almost doubled that in 2015, the Community Index in both years was almost identical. Also diversity indices and evenness index were very similar in both years compared. Granivorous birds were the most numerous feeding guild. Their contribution was similar in 2014 and 2015 (46.7 % vs. 43.4 %). Two other feeding guilds, insectivores and frugivores, comprised together more than 50 % in both years. The number of bird species and species diversity were not influenced by the differential rainfall. However, contrary to expectations, population densities of most bird species (at least the more numerous ones) were higher in the year with lower than in the year with higher rainfall. The number of species and species diversity was similar in the farmland and in neighbouring Kalahari Woodland in a pristine stage. However, population densities of most species were lower in the farmland than in the pristine woodland.

Environmental effects on the structure of polychaete feeding guilds on the beaches of Sepetiba Bay, south-eastern Brazil

2012 ◽  
Vol 93 (4) ◽  
pp. 973-980 ◽  
Author(s):  
Gustavo Mattos ◽  
Ricardo S. Cardoso ◽  
André Souza Dos Santos
Keyword(s):  
Grain Size ◽  
Sandy Beach ◽  
Sandy Beaches ◽  
Feeding Guilds ◽  
Feeding Guild ◽  
Beach Sediment ◽  
Sepetiba Bay ◽  
Importance Index ◽  
Eastern Brazil ◽  
Macrofauna Communities

Several studies have been conducted to explain patterns of the abundance, richness and diversity of sandy-beach macrofauna; however, such analyses have ignored the overall functional structure of macrofauna communities. Few studies have examined polychaete feeding guilds on sandy beach environments. To examine the effects of environmental factors on polychaete feeding guilds on sandy beaches, 12 sandy beaches from five islands in Sepetiba Bay were sampled. A total of 24 polychaete morphospecies, grouped among 21 families, were identified in these sandy beaches. The polychaete species were classified into 10 feeding guilds, and the SDT guild (suspended-deposit feeders, discretely motile, with tentacles) was the most abundant feeding guild, with 34.2% of total number of organisms. The highest trophic importance index and index of trophic diversity values were recorded on the sheltered beaches. A canonical correspondence analysis showed that the exposure rate, beach length, and grain size of the beach sediment significantly affected the polychaete feeding guild distribution and abundance. We can conclude that sheltered beaches have a higher diversity of feeding guilds than exposed beaches and that the biological descriptors of the feeding guilds are directly associated with the grain size of the sediment.

Sexual Selection and Sexual Dimorphism in Mottled Sculpins

Evolution ◽  
1983 ◽  
Vol 37 (1) ◽  
pp. 96 ◽  
Author(s):  
Jerry F. Downhower ◽  
Luther Brown ◽  
Ronald Pederson ◽  
Gloria Staples
Keyword(s):  
Sexual Selection ◽  
Sexual Dimorphism

scholarly journals Peak shifts and extinction under sex-specific selection

2021 ◽  
Author(s):  
Stephen P. De Lisle
Keyword(s):  
Sexual Selection ◽  
Sexual Dimorphism ◽  
Peak Shift ◽  
Adaptive Landscape ◽  
Population Estimates ◽  
Sexual Antagonism ◽  
Adaptive Landscapes ◽  
Quantitative Genetic ◽  
Complex Adaptive ◽  
The Face

AbstractA well-known property of sexual selection combined with a cross sex genetic correlation (rmf), is that it can facilitate a peak shift on the adaptive landscape. How do these diversifying effects of sexual selection +rmf balance with the constraints imposed by such sexual antagonism, to affect macroevolution of sexual dimorphism? Here, I extend existing quantitative genetic models of evolution on complex adaptive landscapes. Beyond recovering classical predictions for the conditions promoting a peak shift, I show that when rmf is moderate to strong, relatively weak sexual selection is required to induce a peak shift in males only. Increasing the strength of sexual leads to a sexually-concordant peak shift, suggesting that macroevolutionary rates of sexual dimorphism may be largely decoupled from the strength of within-population sexual selection. Accounting explicitly for demography further reveals that sex-specific peak shifts may be more likely to be successful than concordant shifts in the face of extinction, especially when natural selection is strong. An overarching conclusion is that macroevolutionary patterns of sexual dimorphism are unlikely to be readily explained by within-population estimates of selection or constraint alone.

Tourism Migration in South Africa

2017 ◽  
Vol 8 (1) ◽  
pp. 47-60
Author(s):  
Unathi Sonwabile Henama ◽  
Portia Pearl Siyanda Sifolo
Keyword(s):  
South Africa ◽  
South African ◽  
Critical Phenomenon ◽  
Economic Benefits ◽  
Tourism Industry ◽  
Future Prospects ◽  
Volunteer Tourism ◽  
Migration Dynamics ◽  
And Migration ◽  
Almost All

This article explores the tourism migration within the South African context, thereby focusing on the current dynamics, challenges and future prospects. Tourism and migration are significant towards globalisation. Almost all countries have jumped on the tourism bandwagon as a result of the positive economic benefits that include improving the balance of payments, attracting foreign exchange, and increasing state coffers through the taxation of non-residents. South Africa has also adopted tourism into the developmental policies. Although Africa's share of the global tourism market remains less than 10%, the continental bodies such as the African Union under the wing NEPAD recognises that tourism and migration as an important factor to societies. This paper adopts the content analysis to address the tourism migration, dynamics, challenges and future prospects as a critical phenomenon. Tourism has deep characteristics of a plantation economy that does not benefit the majority of the societies, particularly in South Africa. Despite being a geographical dispersed country, the tourism industry in South Africa faces numerous challenges such as the integration of Black South Africans as product owners; reported high rates of crimes, lack of integration of locals in the tourism industry, the lack of aviation competition, paucity of ports of entry, and most recently the cyber-crime and the visa regulations etc. However, South African tourism remains resilient as a major destination due to its fauna and flora and increasing market niches are developing such as adventure tourism, health tourism and volunteer tourism. South Africa plans to be one of the top 20 destinations by 2020; steps are in place to ensure that South Africa achieves this objective.

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