scholarly journals Is new spread of the European beaver in Pannonian basin an evidence of the species recovery?

2016 ◽  
Vol 2 (2) ◽  
pp. 44-63 ◽  
Author(s):  
Alexander Čanády ◽  
Peter Krišovský ◽  
Bálint Bajomi ◽  
Attila Huber ◽  
Dávid Czabán ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
New Records ◽  
Pannonian Basin ◽  
European Beaver ◽  
Potential Population ◽  
The City ◽  
Important Evidence ◽  
Exact Origin ◽  
Different Origin

Abstract Abstract: During fieldwork from 6 June to 20 July 2016, the first records of the European beaver (Castor fiber) in south-eastern Slovakia were made. Beavers are mainly nocturnal animals, and as such, they are rarely observed; therefore, our observations were based on searching for beaver presence signs: damaged trees, dams, signs of food consumption (chewed/felled trees) and footprints in the mud. The southern part of the Košická kotlina basin, from the city of Košice down to the state border and the surrounding villages in Hungary, was checked. We found two beaver locations via feeding signs in the vicinity of the Slovakia–Hungary state border, at the villages of Milhosť (Miglécnémeti) and Buzica (Buzita), in Slovakia. According to our calculations, the present total beaver population in Hungary is between 4,000 and 5,000 and 14,600–18,300 beavers with potential support. For Slovakia, we estimated the potential population size to be 7,700–9,600. Our findings in northern Pannonian lowland (Slovakia–Hungary border) are an important evidence of beaver expansion. Although we don’t know the exact origin of investigated population, these new records indicate the possibility of merging the populations of different origin, which could enable gene flow and increase the genetic diversity. This could lead to improved recovery of species and its stabilisation in nature. However, it is necessary to carry out a detailed investigation of the presence of beaver in these regions in future.

Genetic rescue by augmenting gene flow

2017 ◽  
Author(s):  
Richard Frankham ◽  
Jonathan D. Ballou ◽  
Katherine Ralls ◽  
Mark D. B. Eldridge ◽  
Michele R. Dudash ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Inbreeding Coefficient ◽  
Outbreeding Depression ◽  
Genetic Rescue ◽  
Evolutionary Potential ◽  
Beneficial Effects ◽  
The Difference ◽  
Inbred Populations ◽  
Harmful Effects

Inbreeding is reduced and genetic diversity enhanced when a small isolated inbred population is crossed to another unrelated population. Crossing can have beneficial or harmful effects on fitness, but beneficial effects predominate, and the risks of harmful ones (outbreeding depression) can be predicted and avoided. For crosses with a low risk of outbreeding depression, there are large and consistent benefits on fitness that persist across generations in outbreeding species. Benefits are greater in species that naturally outbreed than those that inbreed, and increase with the difference in inbreeding coefficient between crossed and inbred populations in mothers and zygotes. However, benefits are similar across invertebrates, vertebrates and plants. There are also important benefits for evolutionary potential of crossing between populations.

scholarly journals Mitogenomics of the endangered Mediterranean monk seal (Monachus monachus) reveals dramatic loss of diversity and supports historical gene-flow between Atlantic and eastern Mediterranean populations

2020 ◽  
Author(s):  
Alba Rey-Iglesia ◽  
Philippe Gaubert ◽  
Gonçalo Espregueira Themudo ◽  
Rosa Pires ◽  
Constanza De La Fuente ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
North Atlantic ◽  
Marine Mammals ◽  
Eastern Mediterranean ◽  
The Black Sea ◽  
Mediterranean Populations ◽  
Geographic Ranges ◽  
Western Sahara ◽  
The Mediterranean

Abstract The Mediterranean monk seal Monachus monachus is one of the most threatened marine mammals, with only 600–700 individuals restricted to three populations off the coast of Western Sahara and Madeira (North Atlantic) and between Greece and Turkey (eastern Mediterranean). Its original range was from the Black Sea (eastern Mediterranean) to Gambia (western African coast), but was drastically reduced by commercial hunting and human persecution since the early stages of marine exploitation. We here analyse 42 mitogenomes of Mediterranean monk seals, from across their present and historical geographic ranges to assess the species population dynamics over time. Our data show a decrease in genetic diversity in the last 200 years. Extant individuals presented an almost four-fold reduction in genetic diversity when compared to historical specimens. We also detect, for the first time, a clear segregation between the two North Atlantic populations, Madeira and Cabo Blanco, regardless of their geographical proximity. Moreover, we show the presence of historical gene-flow between the two water basins, the Atlantic Ocean and the Mediterranean Sea, and the presence of at least one extinct maternal lineage in the Mediterranean. Our work demonstrates the advantages of using full mitogenomes in phylogeographic and conservation genomic studies of threatened species.

Genetic diversity, population structure and gene flow pattern among populations of Lasiurus sindicus Henr. - an endemic, C4 grass of Indian Thar desert

Plant Gene ◽  
2020 ◽  
Vol 21 ◽  
pp. 100206 ◽  
Author(s):  
Bhuwnesh Goswami ◽  
Rekha Rankawat ◽  
Wahlang Daniel Regie ◽  
Bhana Ram Gadi ◽  
Satyawada Rama Rao
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Gene Flow ◽  
Flow Pattern ◽  
Thar Desert ◽  
C4 Grass

Introgression between non-sister species of honeyeaters (Aves: Meliphagidae) several million years after speciation

2019 ◽  
Vol 128 (3) ◽  
pp. 583-591
Author(s):  
Leo Joseph ◽  
Alex Drew ◽  
Ian J Mason ◽  
Jeffrey L Peters
Keyword(s):  
Gene Flow ◽  
Reproductive Isolation ◽  
Sex Chromosomes ◽  
Common Ancestor ◽  
Sister Species ◽  
Species Boundaries ◽  
North Eastern ◽  
The City

Abstract We reassessed whether two parapatric non-sister Australian honeyeater species (Aves: Meliphagidae), varied and mangrove honeyeaters (Gavicalis versicolor and G. fasciogularis, respectively), that diverged from a common ancestor c. 2.5 Mya intergrade in the Townsville area of north-eastern Queensland. Consistent with a previous specimen-based study, by using genomics methods we show one-way gene flow for autosomal but not Z-linked markers from varied into mangrove honeyeaters. Introgression barely extends south of the area of parapatry in and around the city of Townsville. While demonstrating the long-term porosity of species boundaries over several million years, our data also suggest a clear role of sex chromosomes in maintaining reproductive isolation.

Gene flow interruption in a recently human-modified landscape: The value of isolated trees for the maintenance of genetic diversity in a Mexican endemic red oak

2017 ◽  
Vol 390 ◽  
pp. 27-35 ◽  
Author(s):  
Ken Oyama ◽  
María Luisa Herrera-Arroyo ◽  
Víctor Rocha-Ramírez ◽  
Julieta Benítez-Malvido ◽  
Eduardo Ruiz-Sánchez ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Red Oak ◽  
Isolated Trees ◽  
Flow Interruption

scholarly journals Evolutionary history and genetic connectivity across highly fragmented populations of an endangered daisy

Heredity ◽  
2021 ◽  
Author(s):  
Yael S. Rodger ◽  
Alexandra Pavlova ◽  
Steve Sinclair ◽  
Melinda Pickup ◽  
Paul Sunnucks
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Differentiation ◽  
Evolutionary History ◽  
Livestock Grazing ◽  
Genetic Connectivity ◽  
Evolutionary Divergence ◽  
Common Component ◽  
A Genome ◽  
Eastern Australia

AbstractConservation management can be aided by knowledge of genetic diversity and evolutionary history, so that ecological and evolutionary processes can be preserved. The Button Wrinklewort daisy (Rutidosis leptorrhynchoides) was a common component of grassy ecosystems in south-eastern Australia. It is now endangered due to extensive habitat loss and the impacts of livestock grazing, and is currently restricted to a few small populations in two regions >500 km apart, one in Victoria, the other in the Australian Capital Territory and nearby New South Wales (ACT/NSW). Using a genome-wide SNP dataset, we assessed patterns of genetic structure and genetic differentiation of 12 natural diploid populations. We estimated intrapopulation genetic diversity to scope sources for genetic management. Bayesian clustering and principal coordinate analyses showed strong population genetic differentiation between the two regions, and substantial substructure within ACT/NSW. A coalescent tree-building approach implemented in SNAPP indicated evolutionary divergence between the two distant regions. Among the populations screened, the last two known remaining Victorian populations had the highest genetic diversity, despite having among the lowest recent census sizes. A maximum likelihood population tree method implemented in TreeMix suggested little or no recent gene flow except potentially between very close neighbours. Populations that were more genetically distinctive had lower genetic diversity, suggesting that drift in isolation is likely driving population differentiation though loss of diversity, hence re-establishing gene flow among them is desirable. These results provide background knowledge for evidence-based conservation and support genetic rescue within and between regions to elevate genetic diversity and alleviate inbreeding.

scholarly journals Genetic structure and diversity of the mustard hill coral Porites astreoides along the Florida Keys reef tract

2021 ◽  
Vol 51 (4) ◽  
Author(s):  
Dominique N. Gallery ◽  
Michelle L. Green ◽  
Ilsa B. Kuffner ◽  
Elizabeth A. Lenz ◽  
Lauren T. Toth
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Relatedness ◽  
Florida Keys ◽  
Genetic Population ◽  
High Genetic Diversity ◽  
Western Atlantic ◽  
Porites Astreoides ◽  
Single Well ◽  
Reef Tract

AbstractIncreases in local and global stressors have led to major declines in coral populations throughout the western Atlantic. While abundances of other species have declined, however, the relative abundance of the mustard hill coral, Porites astreoides, has increased. Porites astreoides is relatively resilient to some stressors, and because of its mixed reproductive strategies, its populations often recover quickly following disturbances. The ability for P. astreoides to continue as a potential “winner” in western Atlantic reefs relies on maintaining sufficient genetic variation within populations to support acclimatization and adaptation to current and future environmental change. Without high genetic diversity and gene flow within the population, it would have limited capacity for adaptation and the species’ competitive advantages could be short-lived. In this study, we determined the genetic relatedness of 37 P. astreoides colonies at four shallow reefs along the offshore Florida Keys Reef Tract (FKRT), a region particularly hard-hit by recent disturbances. Using previously designed microsatellite markers, we determined the genetic diversity and connectivity of individuals among and between sites. Our results suggest that the FKRT likely contains a single, well-mixed genetic population of P. astreoides, with high levels of gene flow and evidence for larval migration throughout the region. This suggests that regional populations of P. astreoides likely have a higher chance of maintaining resilience than many other western Atlantic species as they face current and future disturbances.

Excavations in the City of London: First Interim Report, 1974–1975

1977 ◽  
Vol 57 (1) ◽  
pp. 31-66 ◽  
Author(s):  
Brian Hobley ◽  
John Schofield ◽  
Tony Dyson ◽  
Peter R. V. Marsden ◽  
Charles Hill ◽  
...  
Keyword(s):  
Urban Archaeology ◽  
Interim Report ◽  
Set Up ◽  
City Of London ◽  
First Time ◽  
The City ◽  
Important Evidence

SummaryThe Department of Urban Archaeology, City of London, was set up in December 1973 as part of Guildhall Museum, now the Museum of London. Since then it has excavated sixteen sites and carried out numerous watching briefs. Most of the formal excavations have been conducted on the vital waterfront sites, made available for the first time, and on the Roman and medieval defences of the City. Important evidence of the elusive Saxon occupation is gradually coming to light, and the work is accompanied by specialist research, particularly finds, environmental and documentary.

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