Differentiation and Interrelations of Two Representatives of <i>Laudakia stellio</i> Complex (Reptilia: Agamidae) in Israel

Field studies were conducted in Central Negev within the breeding range of Laudakia stellio brachydactyla and in NE Israel (Qyriat Shemona) in the range of an unnamed form (tentatively “Near-East Rock Agama”), during March – May 1996. Additional data have been collected in Jerusalem at a distance of ca. 110 km from the first and about 170 km from the second study sites. A total of 63 individuals were caught and examined. The animals were marked and their subsequent movements were followed. Social and signal behavior of both forms were described and compared. Lizards from Negev and Qyriat Shemona differ from each other sharply in external morphology, habitat preference, population structure, and behavior. The differences obviously exceed the subspecies level. At the same time, the lizards from Jerusalem tend to be intermediate morphologically between those from both above-named localities, which permits admitting the existence of a limited gene flow between lizard populations of Negev and northern Israel. The lizards from NE Israel apparently do not belong to the nominate subspecies of L. stellio and should be regarded as one more subspecies within the species.

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New evidence corroborates population differentiation in Xanthoria parietina

The Lichenologist ◽

10.1017/s0024282907006780 ◽

2007 ◽

Vol 39 (3) ◽

pp. 259-271 ◽

Cited By ~ 16

Author(s):

Louise LINDBLOM ◽

Stefan EKMAN

Keyword(s):

Population Structure ◽

Gene Flow ◽

Nuclear Ribosomal Dna ◽

Habitat Isolation ◽

Restricted Gene Flow ◽

Its2 Region ◽

Sequence Variations ◽

Xanthoria Parietina ◽

Study Sites ◽

New Evidence

Abstract:In order to examine genetic variation and population structure of the widespread lichen-forming ascomycete Xanthoria parietina from similar habitats, but different sites in Scandinavia, we investigated seven populations in Scania, southernmost Sweden, and compared the results with a corresponding study on Storfosna, central Norway. Sequence variations of the nuclear ribosomal DNA were used as molecular markers, for both a part of the IGS region and the complete ITS1-5.8S-ITS2 region. The amount of genetic variability observed was comparable in the two investigations. Divergence between populations in different habitats found in the previous study was also present in this study. Xanthoria parietina is genetically differentiated between habitats with no evidence of restricted gene flow between populations in the same habitat at the present spatial scale, at least at sites along the coast of Scandinavia. Differentiation between habitats is considerable at both study sites, which we attribute to restricted gene flow between habitats, i.e. habitat isolation.

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Are there populations suffering genetic erosion that would benefit from gene flow?

A Practical Guide for Genetic Management of Fragmented Animal and Plant Populations ◽

10.1093/oso/9780198783411.003.0007 ◽

2019 ◽

pp. 97-114

Author(s):

Richard Frankham ◽

Jonathan D. Ballou ◽

Katherine Ralls ◽

Mark D. B. Eldridge ◽

Michele R. Dudash ◽

...

Keyword(s):

Population Structure ◽

Gene Flow ◽

Genetic Differentiation ◽

Paradigm Shift ◽

Genetic Erosion ◽

Genetic Rescue ◽

Limited Gene Flow

Evidence of population structure and limited gene flow often leads to the questionable conclusion that populations should be managed as separate unit. A paradigm shift is needed where evidence of genetic differentiation among populations is followed by an assessment of whether populations are suffering genetic erosion, whether there are other populations to which they could be crossed, and whether the crosses would be beneficial, or harmful, and if beneficial, whether the benefits would be large enough to justify a genetic rescue attempt. Here we address these questions based on the principles established in the preceding chapters.

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LANDSCAPE GENOMICS OFPOPULUS TRICHOCARPA: THE ROLE OF HYBRIDIZATION, LIMITED GENE FLOW, AND NATURAL SELECTION IN SHAPING PATTERNS OF POPULATION STRUCTURE

Evolution ◽

10.1111/evo.12497 ◽

2014 ◽

Vol 68 (11) ◽

pp. 3260-3280 ◽

Cited By ~ 63

Author(s):

Armando Geraldes ◽

Nima Farzaneh ◽

Christopher J. Grassa ◽

Athena D. McKown ◽

Robert D. Guy ◽

...

Keyword(s):

Population Structure ◽

Gene Flow ◽

Natural Selection ◽

Landscape Genomics ◽

Limited Gene Flow

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Population fragmentation causes inadequate gene flow and increases extinction risk

10.1093/oso/9780198783398.003.0005 ◽

2017 ◽

Author(s):

Richard Frankham ◽

Jonathan D. Ballou ◽

Katherine Ralls ◽

Mark D. B. Eldridge ◽

Michele R. Dudash ◽

...

Keyword(s):

Gene Flow ◽

Extinction Risk ◽

Random Mating ◽

Large Population ◽

Isolated Population ◽

Population Fragmentation ◽

Single Population ◽

Total Size ◽

Limited Gene Flow

Most species now have fragmented distributions, often with adverse genetic consequences. The genetic impacts of population fragmentation depend critically upon gene flow among fragments and their effective sizes. Fragmentation with cessation of gene flow is highly harmful in the long term, leading to greater inbreeding, increased loss of genetic diversity, decreased likelihood of evolutionary adaptation and elevated extinction risk, when compared to a single population of the same total size. The consequences of fragmentation with limited gene flow typically lie between those for a large population with random mating and isolated population fragments with no gene flow.

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Cell Cycle, Division Rate, and Feeding of the Heterotroph Phalacroma rotundatum in a Chilean Fjord

Microorganisms ◽

10.3390/microorganisms7100451 ◽

2019 ◽

Vol 7 (10) ◽

pp. 451

Author(s):

Patricio A. Díaz ◽

Iván Pérez-Santos ◽

Gonzalo Álvarez ◽

Michael Araya ◽

Francisco Álvarez ◽

...

Keyword(s):

Cell Cycle ◽

Austral Summer ◽

Field Studies ◽

Local Characteristic ◽

Reference List ◽

Shellfish Poisoning ◽

Division Rate ◽

Bottom Waters ◽

Harmful Microalgae ◽

And Behavior

Phalacroma rotundatum is a rare cosmopolitan heterotrophic dinoflagellate. This species, included in the IOC-UNESCO Taxonomic Reference List of Harmful Microalgae, may be a diarrhetic shellfish poisoning (DSP) toxin vector, but little is known about its ecophysiology and behavior. A vertical net haul collected during the austral summer of 2018 in Reloncaví Sound (Chilean Patagonia) revealed an unusually abundant population of P. rotundatum and prompted intensive 24 h sampling on 16–17 January to study the cell cycle and feeding behavior of this species. Hydrographic measurements from a buoy revealed the local characteristic estuarine circulation, with a brackish surface layer (salinity 26–28) separated from saltier, colder bottom waters by a pycnocline at a depth modulated by the tidal regime. A high proportion of P. rotundatum cells were packed with digestive vacuoles (peak of 70% at 14:00), and phased cell division (µ = 0.46 d−1) occurred 3 h after sunrise. The division time (TD) was 2 h. This is the first cell cycle study of P. rotundatum. The results here disagree with those of previous field studies that considered asynchronous division in some Dinophysis species to be related to heterotrophic feeding. They also question the very specific prey requirements, Tiarina fusus, reported for P. rotundatum in northern Europe.

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Population genetics of Aedes albopictus (Diptera: Culicidae) in its native range in Lao People’s Democratic Republic

Parasites & Vectors ◽

10.1186/s13071-019-3740-0 ◽

2019 ◽

Vol 12 (1) ◽

Author(s):

Maysa Tiemi Motoki ◽

Dina Madera Fonseca ◽

Elliott Frederic Miot ◽

Bruna Demari-Silva ◽

Phoutmany Thammavong ◽

...

Keyword(s):

Population Structure ◽

Gene Flow ◽

Aedes Albopictus ◽

Isolation By Distance ◽

Genetic Locus ◽

Lao Pdr ◽

Phylogenetic Network ◽

Population Expansion ◽

Recent Population Expansion ◽

The Usa

Abstract Background The Asian tiger mosquito, Aedes (Stegomyia) albopictus (Skuse) is an important worldwide invasive species and can be a locally important vector of chikungunya, dengue and, potentially, Zika. This species is native to Southeast Asia where populations thrive in both temperate and tropical climates. A better understanding of the population structure of Ae. albopictus in Lao PDR is very important in order to support the implementation of strategies for diseases prevention and vector control. In the present study, we investigated the genetic variability of Ae. albopictus across a north-south transect in Lao PDR. Methods We used variability in a 1337-bp fragment of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1), to assess the population structure of Ae. albopictus in Lao PDR. For context, we also examined variability at the same genetic locus in samples of Ae. albopictus from Thailand, China, Taiwan, Japan, Singapore, Italy and the USA. Results We observed very high levels of genetic polymorphism with 46 novel haplotypes in Ae. albopictus from 9 localities in Lao PDR and Thailand populations. Significant differences were observed between the Luangnamtha population and other locations in Lao PDR. However, we found no evidence of isolation by distance. There was overall little genetic structure indicating ongoing and frequent gene flow among populations or a recent population expansion. Indeed, the neutrality test supported population expansion in Laotian Ae. albopictus and mismatch distribution analyses showed a lack of low frequency alleles, a pattern often seen in bottlenecked populations. When samples from Lao PDR were analyzed together with samples from Thailand, China, Taiwan, Japan, Singapore, Italy and the USA, phylogenetic network and Bayesian cluster analysis showed that most populations from tropical/subtropical regions are more genetically related to each other, than populations from temperate regions. Similarly, most populations from temperate regions are more genetically related to each other, than those from tropical/subtropical regions. Conclusions Aedes albopictus in Lao PDR are genetically related to populations from tropical/subtropical regions (i.e. Thailand, Singapore, and California and Texas in the USA). The extensive gene flow among locations in Lao PDR indicates that local control is undermined by repeated introductions from untreated sites.

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Distribution and Seasonality of Macroalgae on Oyster Communities of Central Chesapeake Bay

Botanica Marina ◽

10.1515/botm-1980-1108 ◽

1980 ◽

Vol 23 (11) ◽

Cited By ~ 11

Author(s):

Judith L. Connor

Keyword(s):

Life History ◽

Sexual Reproduction ◽

Chesapeake Bay ◽

Physical Environment ◽

Algal Species ◽

Light Availability ◽

Field Studies ◽

Spatial And Temporal Distributions ◽

Red Algal ◽

Study Sites

AbstractField studies of the benthic macroalgae of fifteen selected Chesapeake Bay oyster communities were conducted over a period of a year (March 1977 to February 1978). Algal distribu tion and seasonal occurrence were studied in relation to changes in the physical environment. Salinity, temperature, and light availability were important factors in the spatial and temporal distributions of algae in these subtidal habitats.Seventeen species of Chlorophyta, Phaeophyta, and Rhodophyta were recorded from the fifteen study sites distributed over 130 kilometers within the Maryland portion of Chesapeake Bay. Species of Chlorophyta were associated with oyster communities throughout the year of study with maximum numbers of species and maximum biomass occurring in spring. Only once was a member of the Phaeophyta encountered; a single filamentous species, Ectocarpus, was collected during winter. Species of Rhodophyta were present throughout the year at the study sites.Most of the algae collected reproduced asexually by spores and/or vegetative fragments. Sexual reproduction occurred in some of the red algal species. The presence of tetrasporic and cystocarpic plants of Dasya baillouviana and Polysiphonia harveyi var. olneyi may indicate that the usual triphasic Florideophycean life history occurs in this estuary.

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