Intraspecific phenotypic variation in functional traits of a generalist predator in an agricultural landscape

2019 ◽  
Vol 278 ◽  
pp. 35-42
Author(s):  
Radek Michalko ◽  
Viktoriya Dvoryankina
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Dèdéou A. Tchokponhoué ◽  
Enoch G. Achigan-Dako ◽  
Sognigbé N’Danikou ◽  
Daniel Nyadanu ◽  
Rémi Kahane ◽  
...  

Abstract The miracle plant Synsepalum dulcificum is a multipurpose natural sweetener and a promising West African orphan fruit shrub candidate for genetic improvement. Unfortunately, basic knowledge such as phenotypic variation and inheritance estimates required for implementing a breeding program are still lacking. A set of 203 accessions were sampled in two habitats from seven populations spread across the Dahomey Gap (DG) and the Upper Guinea forest (UG) in West Africa. The phenotypic diversity and allometric relationships among functional traits were analysed; the broad-sense heritability was estimated for fruit-traits, and a mini-core collection was developed in the species. Quantitative variation in tree- and fruit-traits was recorded, and multivariate analyses were performed to assess relationships among accessions, whereas heritability was estimated using the coefficient of repeatability. Tree-traits observed in S. dulcificum were more variable than fruit-traits. While habitat-type only affected tree-traits, the provenance population significantly affected both fruit- and tree-traits, with the UG populations outperforming the DG ones. Significant correlations were observed among fruit-traits on one hand, and among tree-traits on the other hand, whereas poor correlations were observed between tree- and fruit-traits. The multivariate analysis grouped accessions in three clusters. Promising individuals for high fruit mass and pulp-dense genotypes’ selection were identified within clusters. Repeatability estimates for fruit-traits ranged from 0.015 (edible ratio) to 0.88 (fruit mass). The Core Hunter algorithm enabled the extraction of 41 individuals as robust representatives of the initial set of 203 accessions, and the mapping of this core collection suggested Dahomey Gap as a centre of diversity of the species. These original findings offer opportunities, not only for the genetic improvement of S. dulcificum, but also for targeted ex-situ conservation in the species.


2021 ◽  
Author(s):  
Benjamin Yeboah Ofori ◽  
John Bosu Mensah ◽  
Roger Sigismund Anderson ◽  
Daniel Korley Attuquayefio

AbstractLand use and land cover change (LULCC) are major drivers of global biodiversity loss. The conversion of natural habitats into human-modified landscapes poses novel and multifaceted environmental stressors to organisms, influencing their ecology, physiology, life history and fitness. Although the effects of LULCC have been studied extensively at the community level, there is scant information about its effect on population and individual characteristics. We assessed the diet composition, body condition, and sexual size dimorphism of the common African toad (Amietophrynus regularis) in urban and agricultural landscape. Diet composition was evaluated using gut content analysis, while body condition was measured using residual mass index. Overall, 935 prey items comprising six classes, at least 18 orders and 31 families were obtained from toads. This broad dietary niche suggested that Amietophrynus regularis is a generalist predator. The family Formicidae was the most consumed prey item, with a frequency of occurrence above 80% at both sites. We found no sex- or habitat-biased dietary partitioning in the toads. A statistically significant positive correlation existed between snout-vent-length (SVL) and diversity of prey items (Pearson’s correlation r = 0.999, p ≤ 0.0001) for toads from farmland, which also had better body conditions. The toads showed female-biased sexual size dimorphism, but males had longer tibio-fibula, radio-ulna, foot, and distal fore limbs. This study is probably the first to assess the diet composition, body condition and sexual size dimorphism of Amietophrynus regularis simultaneously. The ecological, evolutionary and conservation implications of our findings are discussed.


2020 ◽  
Vol 35 (7) ◽  
pp. 1667-1681 ◽  
Author(s):  
Ülo Väli ◽  
Paweł Mirski ◽  
Gunnar Sein ◽  
Urmas Abel ◽  
Grete Tõnisalu ◽  
...  

2016 ◽  
Vol 553 ◽  
pp. 111-123 ◽  
Author(s):  
C Lagrue ◽  
K Heaphy ◽  
B Presswell ◽  
R Poulin

2019 ◽  
Vol 46 (1) ◽  
pp. 63-74
Author(s):  
Stefano Mattioli

The rediscovery of the original, unedited Latin manuscript of Georg Wilhelm Steller's “De bestiis marinis” (“On marine mammals”), first published in 1751, calls for a new translation into English. The main part of the treatise contains detailed descriptions of four marine mammals, but the introduction is devoted to more general issues, including innovative speculation on morphology, ecology and biogeography, anticipating arguments and concepts of modern biology. Steller noted early that climate and food have a direct influence on body size, pelage and functional traits of mammals, potentially affecting reversible changes (phenotypic plasticity). Feeding and other behavioural habits have an impact on the geographical distribution of mammals. Species with a broad diet tend to have a wide distribution, whereas animals with a narrow diet more likely have only a restricted range. According to Steller, both sea and land then still concealed countless animals unknown to science.


Diabetes ◽  
1979 ◽  
Vol 28 (10) ◽  
pp. 937-942 ◽  
Author(s):  
P. J. Savage ◽  
P. H. Bennett ◽  
R. G. Senter ◽  
M. Miller

2018 ◽  
Vol 15 (1) ◽  
Author(s):  
Nirmala Dorasamy ◽  
Olayemi Bakre

The majority of the South African rural populace is directly or indirectly engaged in agricultural practices to earn a livelihood. However, impediments such as climate change, water shortages, and inadequacy of institutional support have undermined these once thriving subsistence farming communities. Furthermore, poor leadership in hydrology, coupled with a lack of depth in skills at all government levels to facilitate the understanding of the importance of groundwater, has made it near impossible for subsistence farmers to benefit optimally from groundwater. The 2012 drought experienced in South Africa paralysed several subsistence farming communities in KwaZulu-Natal. To revamp subsistence farming and assist these farmers across South Africa, the Department of Water and Sanitation launched interventions, but despite the enormous resources expended, indicators (e.g. unsustainable farming practices, poor crop yield, pitiable living conditions, and poor standards of living) provide evidence that these interventions have not yielded the desired results. This paper seeks to suggest practicable interventions aimed at reducing the vulnerability of subsistence farmers in KwaZulu-Natal. The study pursued a qualitative approach in that it solicited the views of experts on groundwater and in related fields to gain an in-depth perspective. Some of the core challenges undermining the sustainability and growth of subsistence farming in the study area were found to be the inadequacy of experts on groundwater, water shortages, institutional deficiencies, lack of political will, and lack of coordination among stakeholders. Pragmatic recommendations are made to address these challenges, among other things to encourage a South African-Chinese partnership in the hydrology sector.


Sign in / Sign up

Export Citation Format

Share Document