scholarly journals Loss of genetic diversity and increased genetic structuring in response to forest area reduction in a ground dwelling insect: a case study of the flightless carabid beetleCarabus problematicus(Coleoptera, Carabidae)

2012 ◽  
Vol 6 (4) ◽  
pp. 473-482 ◽  
Author(s):  
Eva Gaublomme ◽  
Kevin Maebe ◽  
Karine Van Doninck ◽  
Hilde Dhuyvetter ◽  
Xiang Li ◽  
...  
2009 ◽  
Vol 30 (1) ◽  
pp. 127-133 ◽  
Author(s):  
Sylvain Dubey ◽  
Luca Fumagalli ◽  
Sylvain Ursenbacher ◽  
Jérôme Pellet

AbstractThe survival of threatened species as the European tree frog (Hyla arborea) is strongly dependent on the genetic variability within populations, as well as gene flow between them. In Switzerland, only two sectors in its western part still harbour metapopulations. The first is characterised by a very heterogeneous and urbanized landscape, while the second is characterised by a uninterrupted array of suitable habitats. In this study, six microsatellite loci were used to establish levels of genetic differentiation among the populations from the two different locations. The results show that the metapopulations have: (i) weak levels of genetic differentiation (FST within metapopulation ≈ 0.04), (ii) no difference in levels of genetic structuring between them, (iii) significant (p = 0.019) differences in terms of genetic diversity (Hs) and observed heterozygozity (Ho), the metapopulation located in a disturbed landscape showing lower values. Our results suggest that even if the dispersal of H. arborea among contiguous ponds seems to be efficient in areas of heterogeneous landscape, a loss of genetic diversity can occur.


2019 ◽  
Vol 67 (1) ◽  
pp. 38
Author(s):  
Peter B. S. Spencer ◽  
Karlene Bain ◽  
Matthew W. Hayward ◽  
Mia Hillyer ◽  
J. A. Tony Friend

Understanding the spatial structure of populations is important in developing effective management options for threatened species, and for managing habitat connectivity for metapopulation function, and for demographic and genetic heterogeneity. We used genetic information to investigate the structure of populations of the quokka, Setonix brachyurus, in south-west Western Australia. We hypothesised that movement between known populations would be relatively rare and result in significant genetic structuring. Genetic analyses from 412 adult individuals at 14 nuclear markers (microsatellite) from 33 sampling locations identified structure, diversity and spatial separation of quokkas across their mainland distribution and on two islands. We identified nine inferred (K = 9) populations of quokka that would be otherwise difficult to define with standard ecological techniques. The highest genetic diversity was evident in a large central population of quokka in the southern forest area and genetic diversity was lower at the peripheries of the distribution. The Rottnest Island population contained 70% of the genetic diversity of the mainland populations but the genetic diversity of animals on Bald Island was markedly lower. Populations of quokka in the northern jarrah forest were the only ones to show evidence of recent or long-term population bottlenecking. Of particular interest was the recently identified population at the Muddy Lakes area (the only remaining locality on the Swan Coastal Plain), which was identified as being genetically associated with the southern forest population. Overall, spatial and population cluster analysis showed small insular populations in the northern jarrah forest area, but in the southern forests there appears to be a large panmictic population.


Author(s):  
Richard Frankham ◽  
Jonathan D. Ballou ◽  
Katherine Ralls ◽  
Mark D. B. Eldridge ◽  
Michele R. Dudash ◽  
...  

Genetic management of fragmented populations involves the application of evolutionary genetic theory and knowledge to alleviate problems due to inbreeding and loss of genetic diversity in small population fragments. Populations evolve through the effects of mutation, natural selection, chance (genetic drift) and gene flow (migration). Large outbreeding, sexually reproducing populations typically contain substantial genetic diversity, while small populations typically contain reduced levels. Genetic impacts of small population size on inbreeding, loss of genetic diversity and population differentiation are determined by the genetically effective population size, which is usually much smaller than the number of individuals.


Diversity ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 343
Author(s):  
Luca Vecchioni ◽  
Federico Marrone ◽  
Marco Arculeo ◽  
Uwe Fritz ◽  
Melita Vamberger

The geographical pattern of genetic diversity was investigated in the endemic Sicilian pond turtle Emys trinacris across its entire distribution range, using 16 microsatellite loci. Overall, 245 specimens of E. trinacris were studied, showing high polymorphic microsatellite loci, with allele numbers ranging from 7 to 30. STRUCTURE and GENELAND analyses showed a noteworthy, geographically based structuring of the studied populations in five well-characterized clusters, supported by a moderate degree of genetic diversity (FST values between 0.075 and 0.160). Possible explanations for the genetic fragmentation observed are provided, where both natural and human-mediated habitat fragmentation of the Sicilian wetlands played a major role in this process. Finally, some conservation and management suggestions aimed at preventing the loss of genetic variability of the species are briefly reported, stressing the importance of considering the five detected clusters as independent Management Units.


2002 ◽  
Vol 78 (4) ◽  
pp. 539-549 ◽  
Author(s):  
Paul D Anderson ◽  
John C Zasada ◽  
Glen W Erickson ◽  
Zigmond A Zasada

A white pine (Pinus strobus L.) stand at the western margin of the species range, approximately 125 years of age at present, was thinned in 1953 from 33.5 m2 ha-1 to target residual basal areas of 18.4, 23.0, 27.5, and 32.1 m2 ha-1 . Repeated measurement over the following 43-years indicated that the greatest total volume production and the greatest number of large diameter trees occurred in the unit of highest residual density. Over time, the distribution of stems was predominantly random although mortality between 1979 and 1996 resulted in a tendency for clumping in the 23.0 and 27.5 m2 ha-1 treatments. DNA analysis indicated that thinning intensity had little effect on the genetic diversity of residual white pine. This study suggests that mature white pine stands in northern Minnesota may be managed at relatively high densities without loss of productivity. However, regardless of overstory density, there was little or no white pine regeneration occurring in this stand. Key words: thinning, growth, genetic diversity, molecular markers, spatial pattern, regeneration


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Agnieszka Sutkowska ◽  
Józef Mitka ◽  
Tomasz Warzecha ◽  
Jakub Bunk ◽  
Julia Rutkowska ◽  
...  

AbstractThe genetic diversity in 11 populations of Gladiolus imbricatus in five mountain ranges, including the Tatra, Pieniny, Gorce, Beskid Niski (Western Carpathians) and Bieszczady Mts (Eastern Carpathians), was studied with inter-simple sequence repeat (ISSR) markers. The species is a perennial plant occurring in open and semi-open sites of anthropogenic origin (meadows and forest margins). We checked a hypothesis on the microrefugial character of the plant populations in the Pieniny Mts, a small calcareous Carpathian range of complicated relief that has never been glaciated. Plant populations in the Tatra and Pieniny Mts had the highest genetic diversity indices, pointing to their long-term persistence. The refugial vs. the non-refugial mountain ranges accounted for a relatively high value of total genetic variation [analysis of molecular variance (AMOVA), 14.12%, p = 0.003]. One of the Pieniny populations was of hybridogenous origin and shared genetic stock with the Tatra population, indicating there is a local genetic melting pot. A weak genetic structuring of populations among particular regions was found (AMOVA, 4.5%, p > 0.05). This could be an effect of the frequent short-distance and sporadic long-distance gene flow. The dispersal of diaspores between the remote populations in the Western Carpathians and Eastern Carpathians could be affected by the historical transportation of flocks of sheep from the Tatra to Bieszczady Mts.


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