Parthenogenesis as a life strategy among mites of the suborder Uropodina (Acari: Mesostigmata)

This paper presents the results of observations concerning the phenomenon of parthenogenesis among European mites of the suborder Uropodina. An analysis of the sex ratios of 66 Polish species revealed that 18 of them (more than one fourth of the examined species) consisted only of females. The authors observed no significant relationship between geographical distribution and the lack of males in the population. Populations consisting entirely of females were observed among widely distributed species as well as among species characterized by narrow geographical ranges. Nonetheless, an increase in the number of parthenogenetic species, especially as a percentage of Middle European and Scandinavian fauna, was also discernible. Species that reproduced without males were associated with forest litter and soil, whereas bisexual species "eagerly" inhabited various relatively unstable and temporary micro environ ments (for instance, dead wood, birds' or small mammals' nests). The authors aim to define the biological role of occasionally appearing males for the species consisting almost entirely of females and discuss ecological and evolutionary aspects of parthenogenesis in mites of the suborder Uropodina.

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Demosponge fauna of Ormonde and Gettysburg Seamounts (Gorringe Bank, north-east Atlantic): diversity and zoogeographical affinities

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315407058584 ◽

2007 ◽

Vol 87 (6) ◽

pp. 1643-1653 ◽

Cited By ~ 20

Author(s):

Joana Xavier ◽

Rob van Soest

Keyword(s):

Shallow Water ◽

Geographical Distribution ◽

Marine Biota ◽

East Atlantic ◽

North East ◽

The North ◽

Gorringe Bank ◽

High Level ◽

Evolutionary Aspects

Seamounts, although abundant features of the world's oceans, constitute one of the least studied marine ecosystems. In the present work we assessed the diversity and zoogeographical affinities of the demosponge assemblages of Gettysburg and Ormonde Seamounts (Gorringe Bank, north-east Atlantic). Twenty-three demosponge species were identified adding to the thirteen previously reported for Gorringe shallow-water. Gorringe's demosponge assemblage was found to be mainly composed of species with a wide Atlanto–Mediterranean distribution (61%) and a group of species (28%) that are endemic to this Bank or have a restricted geographical distribution. This high level of endemism suggests the Gorringe Bank as a hotspot for demosponge fauna in the north-east Atlantic. Gorringe demosponge fauna was found to present an overall moderate similarity to the Mediterranean, Iberian coasts and Macaronesian archipelagos. We compare our findings with patterns reported for fish and molluscan faunas for this Bank and discuss some evolutionary aspects on the role of these ecosystems for the north-east Atlantic marine biota.

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New records and geographic distribution of the sympatric zones of unisexual and bisexual rock lizards of the genus Darevskia in Armenia and adjacent territories

Biodiversity Data Journal ◽

10.3897/bdj.8.e56030 ◽

2020 ◽

Vol 8 ◽

Author(s):

Varos Petrosyan ◽

Fedor Osipov ◽

Vladimir Bobrov ◽

Natalia Dergunova ◽

Ivan Kropachev ◽

...

Keyword(s):

New Records ◽

Parental Species ◽

Reticulate Evolution ◽

Interspecific Hybridisation ◽

Altitudinal Distribution ◽

Bisexual Species ◽

Parthenogenetic Species ◽

Natural Hybridisation ◽

And Bisexual

Caucasian rock lizards of the genus is a unique taxa, including both bisexual and parthenogenetic species. The parthenogenetic species have originated as a result of natural hybridisation between females and males of different bisexual species. The species involved in interspecific hybridisation are called parental. However, sympatric zones (SZ) of unisexual and bisexual rock lizards of the Caucasus are still poorly studied, although they are very important for understanding the role of hybrid individuals of different origin in reticulate evolution. This paper presents the location of the SZs of parthenogenetic and their parental bisexual rock lizards of the genus Darevskia in Armenia and adjacent territories of Georgia and Nagorno-Karabakh. We summarised the locations of the SZs identified from 1957 to the present, based on our field survey data gathered in 2018-2019 and records from publications and museum collections. This dataset includes 39 SZs of three types: SZ of parental bisexual species, SZ of parental species with unisexual species and SZ of the parthenogenetic species. For each zone, species composition, geographical and altitudinal distribution are presented. New records expand our knowledge of the geographical and altitudinal distribution of SZs in these species and provide additional data for understanding the mechanisms of reticulate evolution and hybridogeneous speciation in the past, present and future. The new records, including geographical and altitudinal distributions of three types of SZs, are presented, which expand the previously-known list to 39 locations of contact zones for parthenogenetic and its bisexual parental species of rock lizards of the genus Darevskia in Armenia and the adjacent territories of Georgia and Nagorno-Karabakh.

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Polyketides in insects: ecological role of these widespread chemicals and evolutionary aspects of their biogenesis

Biological Reviews ◽

10.1111/j.1469-185x.2008.00040.x ◽

2008 ◽

Vol 83 (2) ◽

pp. 209-226 ◽

Cited By ~ 38

Author(s):

Florian Pankewitz ◽

Monika Hilker

Keyword(s):

Ecological Role ◽

Evolutionary Aspects

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Small Mammals as Predators of Sawflies

The Canadian Entomologist ◽

10.4039/ent87121-3 ◽

1955 ◽

Vol 87 (3) ◽

pp. 121-123 ◽

Cited By ~ 9

Author(s):

C. H. Buckner

Keyword(s):

Small Mammals ◽

Biological Control Agent ◽

Control Agent ◽

Moderate Risk ◽

Neodiprion Abietis ◽

Ample Opportunity ◽

Pristiphora Erichsonii ◽

Mammalian Predators ◽

One Year

The greatest predatory effect of small mammals is exerted upon insects that spend a portion of their life cycle on the ground or in the soil. Sawflies afford ample opportunity for mammalian predation, since they drop to the ground as mature larvae and spin cocoons in the soil. Such sawflies as Neodiprion abietis Harr., which remain within the cocoon for about three weeks, undergo only moderate risk of being preyed upon by small mammal. However, Pristiphora erichsonii (Htg.) remains within the cocoon from about mid-August until the following June, or even over more than one year, thus greatly extending the vulnerable period. Earlier investigations suggest that small mammals may comprise the largest single biological control agent acting against this insect (Graham 1928, Lejeune 1951), but the exact role of mammalian predators of forest insects has yet to be established.

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The Role of Family and Friends in Return Migration and Its Labor Market Outcomes

Population Research and Policy Review ◽

10.1007/s11113-021-09650-x ◽

2021 ◽

Author(s):

Brian Joseph Gillespie ◽

Clara H. Mulder ◽

Christiane von Reichert

Keyword(s):

Labor Market ◽

Survey Data ◽

Significant Relationship ◽

Return Migration ◽

Labor Market Outcomes ◽

Age Groups ◽

Market Outcomes ◽

Market Stability ◽

Onward Migration

AbstractDrawing on survey data on individuals’ motives for migration in Sweden (N = 2172), we examine the importance of family and friends for return versus onward migration, including their importance for different age groups and in different communities on the rural–urban spectrum. The results point to a significant relationship between the importance of family and return versus onward migration, with family importance decreasing with age among returning migrants. At the same time, the importance of friends for returning increases with age. The findings did not suggest a significant relationship between urbanicity and returning versus migration elsewhere. Based on a subset of respondents who were employed prior to migrating (n = 1056), we further examined labor market outcomes for onward versus returning migrants. The results broadly indicate that return migrations are linked to lower likelihoods of labor market deterioration and improvement, suggesting greater labor market stability for return vis-à-vis onward migrations. However, the importance of family for returning (versus moving elsewhere) is associated with higher likelihoods of labor market deterioration and improvement compared with staying the same, indicating greater volatility in labor market outcomes when the importance of family is considered.

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The Role of Emotionality and Power on Tendency to Unethical Behaviors

International Journal of Human Resource Studies ◽

10.5296/ijhrs.v2i4.2866 ◽

2012 ◽

Vol 2 (4) ◽

pp. 187

Author(s):

Hossein Safarzadeh ◽

Alireza Soloukdar ◽

Ali Alipour ◽

Seyedeh Akram Parpanchi

Keyword(s):

Correlation Coefficient ◽

Organizational Citizenship ◽

Significant Relationship ◽

Independent Variables ◽

Ethical Behaviors ◽

Two Factors ◽

Unethical Behaviors ◽

The Common ◽

Two Independent Variables

Emotion and power have been studied very deeply especially during the last decade; however, the common effects of these two factors on individuals' optional behaviors (organizational citizenship, anti-productivity, unethical behaviors) have been less focused. In the present paper, the role of individuals' emotionality, their interest in power, and their tendency to unethical behaviors will be discussed according to the model of Levine. Three questionnaires were distributed and the collected data were analyzed using Pearson’s Correlation Coefficient, Multiple Regression, and T- test. Findings indicated that there is a significant relationship between the two independent variables of emotionality and power and tendency to unethical behaviors. Moreover, according to the results of the tests, men are more emotion-oriented and power seekers than women. Keywords: Power, Emotion, Ethical Behaviors

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Arthrocladiella mougeotii. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056401371 ◽

1998 ◽

Author(s):

V. P. Heluta

Keyword(s):

Czech Republic ◽

Geographical Distribution ◽

Disease Transmission ◽

Russian Far East ◽

Far East ◽

Republic Of Georgia ◽

Lycium Barbarum ◽

Initial Stage ◽

High Infection

Abstract A description is provided for Arthrocladiella mougeotii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Powdery mildew of Lycium species only. The mycelium, conidiophores, conidia and ascomata form first white, then dirty-grey patches on damaged green parts of the host. Infected parts are deformed slightly and, in cases of high infection, plants can lose their ornamental qualities. Damaged leaves can fall prematurely. HOSTS: Lycium barbarum (= L. europaeum), L. chinense, L. dasystemum, L. halimifolium, L. ovatum, L. potaninii, L. rhombifolium, L. ruthenicum. [Type host - Lycium barbarum] GEOGRAPHICAL DISTRIBUTION: Africa: Canary Islands. Asia (temperate areas only): Armenia, Azerbaijan, China, Republic of Georgia, Israel, Japan, Kazakhstan, Kirghizistan, Korea, Russia (Russian far east), Tadzhikistan, Taiwan, Turkey, Turkmenistan, Uzbekistan. Australasia: New Zealand (introduced). Europe: Austria, Belgium, Bulgaria, Czech Republic, Estonia, France, Germany, Hungary, Italy, Netherlands, Norway, Poland, Rumania, Slovakia, Sweden, Switzerland, UK, Ukraine (southern), former Yugoslavia. North America: USA (introduced). TRANSMISSION: By wind-dispersed conidia. The rôle of ascospores in disease transmission is unknown, although it has been supposed that they can cause the initial stage of the disease.

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PEMBERDAYAAN PETANI PADI DALAM PEMASARAN BERAS KEMAS DI DESA KADUGENEP KECAMATAN PETIR KABUPATEN SERANG

Jurnal Inovasi Penelitian ◽

10.47492/jip.v1i3.85 ◽

2020 ◽

Vol 1 (3) ◽

pp. 317-324

Author(s):

Rizqi Maulana Syifa ◽

Wasrob Nasruddin ◽

Achdiyat Achdiyat

Keyword(s):

Data Mining ◽

Significant Relationship ◽

Rank Correlation ◽

Total Sample ◽

Agricultural Activities ◽

Validity And Reliability ◽

Rice Farmers ◽

The Government ◽

Role Of The Government

Rice commodity is one of the main commodities being cultivated by farmers in Kadugenep Village. .various kinds of agricultural activities carried out by rice farmers in Kadugenep Village, in carrying out agricultural activities not only on production activities or cultivation of plants, but how to market agricultural productsin order to generate profits that can prosper farmers in terms of the economy.the assessment activities have been carried out from March 1 to June 30, 2020, with a total sample of 32 people. Data mining is done by interviews, questionnaires that have been tested for validity and reliability, as well as direct observation. .farmer empowerment levels were analyzed descriptively, factors related to empowerment were analyzed using the Spearmean Rank Correlation, and counseling strategies were analyzed using Kendal's Wbased on the results obtained from interviews and questionnaires given to respondents, showed that 5 people (15.6%) of respondents stated helpless, while 27 people (84.4%) respondents stated helpless. factors related to the role of the government (X2.1) of 0,000 and the role of advisors (X2.2) of 0.001 have a significant relationship to the empowerment of rice farmers in marketing rice packaging. strategies that can be done in increasing the empowerment of rice farmers in marketing rice from the results of the Kendall W analysis, namely by providing counseling about the function of cooperatives as a place for marketing products and functionspackaging with lecture, discussion and demonstration methods as well as extension media used, namely the provision of videos and folders.

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Podosphaera leucotricha. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056400158 ◽

1967 ◽

Author(s):

J. N. Kapoor

Keyword(s):

South Africa ◽

New Zealand ◽

North America ◽

Powdery Mildew ◽

South America ◽

Geographical Distribution ◽

Prunus Persica ◽

Podosphaera Leucotricha

Abstract A description is provided for Podosphaera leucotricha. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Malus spp., chiefly on M. pumila (apple), peach (Prunus persica), quince (Cydonia ualgaris) and Photinia spp. also attacked (Hirata, 1966). Also reported on almond fruit (43, 2544). DISEASE: Powdery mildew of apple. GEOGRAPHICAL DISTRIBUTION: Africa (? Kenya, Rhodaia, South Africa, Tanzania); Asia (China, India, Israel, Japan, U.S.S.R.); Australia and New Zealand, Europe (widely distributed) North America (Canada and U.S.A.); South America (Argentina, Brazil, Chile, Colombia, Peru). (CMI map 118). TRANSMISSION: Overwinters on host as dormant mycdium in blossom buds. The role of deistothecia in overwintering is doubtful. Spread by wind-borne conidia (Anderson, 1956).

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