scholarly journals Rapoport effect in South American Carnivora (Mammalia): null models under geometric and phylogenetic constraints

2002 ◽  
Vol 62 (3) ◽  
pp. 437-444 ◽  
Author(s):  
J. A. F. DINIZ-FILHO ◽  
N. M. TÔRRES

Rapoport effect predicts that species geographic range sizes will increase toward higher latitudes, probably reflecting adaptations to extreme climatic conditions that increase species tolerance. Recently, studies about spatial patterns in species richness and geographic range size may be associated with the geometry of species' ranges. In this context, null models can be used to search for the causal mechanisms associated with these patterns. In this paper, we analyzed Rapoport effect using a null model to evaluate how phylogenetic structure and geometric constraints simultaneously affect latitudinal extents of 40 species of South American terrestrial Carnivora. The latitudinal extents of Carnivora tended to decrease toward Southern latitudes, in the opposite direction expected under a simple Rapoport effect, but in accordance to geometric expectations of position of midpoints in the continent. Using 5000 simulations, it was possible to show that the null regression coefficients of latitudinal extents against midpoints are positively biased, reflecting the geometric constraints in the latitudinal extents. The results were equivalent in phylogenetic and non-phylogenetic analyses. The observed regression coefficient was significantly smaller (line is less inclined) than expected by chance alone, demonstrating that the geometric constraints in the latitudinal extents exist even after controlling for phylogenetic structure in data using eigenvector regressions. This suggests that the "spirit" of Rapoport effect (sensu Lyons & Willig, 1997) could be maintained, i.e., that latitudinal extents in Southern region of the continent are relatively larger than those in Northern regions, even after controlling for phylogenetic effects.

Parasitology ◽  
2018 ◽  
Vol 145 (12) ◽  
pp. 1623-1632
Author(s):  
Boris R. Krasnov ◽  
Georgy I. Shenbrot ◽  
Luther van der Mescht ◽  
Elizabeth M. Warburton ◽  
Irina S. Khokhlova

AbstractTo understand existence, patterns and mechanisms behind phylogenetic heritability in the geographic range size (GRS) of parasites, we measured phylogenetic signal (PS) in the sizes of both regional (within a region) and continental (within a continent) geographic ranges of fleas in five regions. We asked whether (a) GRS is phylogenetically heritable and (b) the manifestation of PS varies between regions. We also asked whether geographic variation in PS reflects the effects of the environment's spatiotemporal stability (e.g. glaciation disrupting geographic ranges) or is associated with time since divergence (accumulation differences among species over time). Support for the former hypothesis would be indicated by stronger PS in southern than in northern regions, whereas support for the latter hypothesis would be shown by stronger PS in regions with a large proportion of species belonging to the derived lineages than in regions with a large proportion of species belonging to the basal lineages. We detected significant PS in both regional and continental GRSs of fleas from Canada and in continental GRS of fleas from Mongolia. No PS was found in the GRS of fleas from Australia and Southern Africa. Venezuelan fleas demonstrated significant PS in regional GRS only. Local Indicators of Phylogenetic Association detected significant local positive autocorrelations of GRS in some clades even in regions in which PS has not been detected across the entire phylogeny. This was mainly characteristic of younger taxa.


2021 ◽  
Author(s):  
Daniel P. Cariveau ◽  
Michael Roswell ◽  
Tina Harrison ◽  
Mark A. Genung ◽  
Jason Gibbs ◽  
...  

Installing pollinator habitat is a ubiquitous conservation tool, but little is known about which pollinator taxa require support, or which benefit from habitat installations. We studied the response of rare and common bees to pollinator habitat enhancement. We used independent regional datasets to designate bee species as common or rare based on their rank according to one of three metrics: a) site occurrence frequency, b) local relative abundance, and c) geographic range size. We asked whether the abundance or richness of rare and common bees were greater in pollinator habitat, relative to old-field controls. Because we used an arbitrary, quantile-based cutoff to categorize species rarity, we conducted sensitivity analysis and controlled for rarity classification errors with a null model. With this null model, we determined whether rare and/or common species responded to pollinator habitat disproportionately, compared to the expectation for "typical" bee species. We found that the number of individuals and of species designated as rare based on local relative abundance was greater in pollinator habitat enhancements. The number of individuals from bee species designated as rare based on site occurrence was lower in pollinator habitat enhancements, but the number of species was not clearly different between habitat types. We did not find a clear positive nor negative effect of habitat enhancement for species designated rare based on geographic range size. For all three rarity metrics, common species increased in abundance and richness in pollinator habitat relative to controls. Null models indicated that in most cases, neither rare nor common species disproportionately benefited from pollinator habitat. Synthesis and Applications: Our results suggest that pollinator habitat can lead to an increase in the abundance and richness of bees, including species that are rare and that are common. However, rare species appeared to respond differently than typical species, and depending on how species were classified as rare, could display muted or even negative responses to habitat enhancement. Targeting rare species with specific floral resources or unique habitat types may lead to better outcomes for rare and threatened species.


2019 ◽  
Vol 44 (4) ◽  
pp. 930-942
Author(s):  
Geraldine A. Allen ◽  
Luc Brouillet ◽  
John C. Semple ◽  
Heidi J. Guest ◽  
Robert Underhill

Abstract—Doellingeria and Eucephalus form the earliest-diverging clade of the North American Astereae lineage. Phylogenetic analyses of both nuclear and plastid sequence data show that the Doellingeria-Eucephalus clade consists of two main subclades that differ from current circumscriptions of the two genera. Doellingeria is the sister group to E. elegans, and the Doellingeria + E. elegans subclade in turn is sister to the subclade containing all remaining species of Eucephalus. In the plastid phylogeny, the two subclades are deeply divergent, a pattern that is consistent with an ancient hybridization event involving ancestral species of the Doellingeria-Eucephalus clade and an ancestral taxon of a related North American or South American group. Divergence of the two Doellingeria-Eucephalus subclades may have occurred in association with northward migration from South American ancestors. We combine these two genera under the older of the two names, Doellingeria, and propose 12 new combinations (10 species and two varieties) for all species of Eucephalus.


2020 ◽  
pp. 33-36
Author(s):  
Е.Л. Макарова ◽  
Л.А. Чистякова ◽  
О.В. Бакланова ◽  
Ю.В. Борцова

Приведены экспериментальные данные оценки по хозяйственно полезным признакам одиннадцати новых партенокарпических гетерозисных гибридов огурца в условиях весенне-летнего оборота Кировской области. Проблема возделывания теплолюбивых культур в северных регионах страны формирует цели селекционных исследований. Выращивание культуры огурца в Кировской области усугубляется неблагоприятными климатическими условиями второй световой зоны (короткая продолжительность вегетационного периода, низкие положительные температуры, заморозки в третьей декаде июля и в первой декаде августа). Цель научной работы – оценка и выявление перспективных партенокарпических гетерозисных гибридов огурца для выращивания в условиях необогреваемых теплиц в весенне-летнем обороте второй световой зоны. Исследования проводили в лаборатории северного овощеводства Кировской области во Всероссийском научно – исследовательском институте овощеводства – филиале ФГБНУ «Федеральный научный центр овощеводства» в условиях поликарбонатных необогреваемых грунтовых теплиц в течение 2018-2019 годах. В результате фенологических наблюдений и оценки биометрических показателей определены раннеспелость, скороспелость и товарность испытуемых партенокарпических гетерозисных гибридов огурца селекции Агрохолдинга «Поиск» и ВНИИО – филиала ФГБНУ «Федеральный научный центр овощеводства»: F1Авоська, F1 Атос, F1 Букет для мамы, F1Малахитовая шкатулка, F1 Мультифрут, F1 Новатор, F1Пилигрим, F1 Спринтер, F1 Реванш, F1 Тонус, F1Экспресс в сравнении с районированным гибридом огурца F1 Каролина. Определено сильное негативное влияние климатических условий второй световой зоны на продолжительность периода «всходы-плодоношение», который в среднем за годы исследований в зависимости от гибрида варьировал от 47 до 55 суток. Установлено, что для получения ранней продукции огурца в условиях поликарбонатных необогреваемых грунтовых теплиц Кировской области следует выращивать гетерозисные партенокарпические гибриды огурца F1Спринтер (3,6 кг/м2), F1 Авоська (2,1 кг/м2) и F1 Атос (2,5 кг/м2). Отмечены партенокарпические гибриды огурца F1 Спринтер и F1 Атос, которые имеют наиболее высокий выход товарной продукции 95,7 и 94,0%, соответственно. Выделен самый урожайный партенокарпический гибрид огурца F1 Новатор (16,1 кг/м2). В результате исследовательской работы рекомендовано выращивать в условиях необогреваемых теплиц весенне-летнего оборота Кировской области партенокарпические гибриды огурца F1 Новатор, F1 Спринтер, F1 Атос и F1 Авоська. The article presents the experimental data on the assessment of economically useful traits of eleven new parthenocarpic heterotic cucumber hybrids under the conditions of the spring-summer turnover of the Kirov region. The problem of cultivation of thermophilic crops, which arises in the northern regions of the country, is one of the stages of breeding research. The cultivation of cucumber in the Kirov region is aggravated by unfavorable climatic conditions of the second light zone (short duration of the growing season, low positive temperatures, frosts in the third decade of July and in the first decade of August). The purpose of the scientific work is to evaluate and identify promising parthenocarpic heterotic hybrids of cucumber for growing in unheated greenhouses in the spring-summer turnover of the second light zone. The research was carried out in the laboratory of northern vegetable growing of the Kirov region at the All-Russian Research Institute of Vegetable Growing - a branch of the Federal State Budgetary Scientific Institution Federal Scientific Vegetable Centre in the conditions of polycarbonate unheated ground greenhouses during 2018-2019. As a result of phenological observations and assessment of biometric indicators, the early maturity, early maturity and marketability of the tested parthenocarpic heterotic cucumber hybrids of the selection of Agroholding Poisk and ARRIVG – a branch of the Federal Scientific Vegetable Centre were determined: F1 Avoska, F1 Atos, F1 Buket dlya mamy, F1 Multifrut, F1 Novator, F1 Piligrim, F1Sprinter, F1 Revansh, F1 Tonus, F1 Express in comparison with the zoned hybrid of cucumber F1 Carolina. A strong negative influence of climatic conditions of the second light zone on the duration of the seedling-fruiting period was determined, which on average over the years of research, depending on the hybrid, varied from 47 to 55 days. It has been established that to obtain early production of cucumber in polycarbonate unheated ground greenhouses of the Kirov region, heterotic parthenocarpic cucumber hybrids F1 Sprinter (3.6 kg/m2), F1 Avoska (2.1 kg/m2) and F1 Atos (2.5 kg/m2). Parthenocarpic cucumber hybrids F1 Sprinter and F1 Atos were noted, which have the highest yield of marketable products, 95.7 and 94.0%, respectively. The most productive parthenocarpic cucumber hybrid F1Novator (16.1 kg/m2) has been identified. As a result of the research work, it was recommended to grow parthenocarpic cucumber hybrids F1Novator, F1 Sprinter, F1 Atos and F1 Avoska under conditions of unheated greenhouses of spring-summer turnover of the Kirov region.


Life ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 420
Author(s):  
María Eugenia Salgado Salomón ◽  
Carolina Barroetaveña ◽  
Tuula Niskanen ◽  
Kare Liimatainen ◽  
Matthew E. Smith ◽  
...  

This paper is a contribution to the current knowledge of taxonomy, ecology and distribution of South American Cortinarius (Pers.) Gray. Cortinarius is among the most widely distributed and species-rich basidiomycete genera occurring with South American Nothofagaceae and species are found in many distinct habitats, including shrublands and forests. Due to their ectomycorrhizal role, Cortinarius species are critical for nutrient cycling in forests, especially at higher latitudes. Some species have also been reported as edible fungi with high nutritional quality. Our aim is to unravel the taxonomy of selected Cortinarius belonging to phlegmacioid and myxotelamonioid species based on morphological and molecular data. After widely sampling Cortinarius specimens in Patagonian Nothofagaceae forests and comparing them to reference collections (including holotypes), we propose five new species of Cortinarius in this work. Phylogenetic analyses of concatenated rDNA ITS-LSU and RPB1 sequences failed to place these new species into known Cortinarius sections or lineages. These findings highlight our knowledge gaps regarding the fungal diversity of South American Nothofagaceae forests. Due to the high diversity of endemic Patagonian taxa, it is clear that the South American Cortinarius diversity needs to be discovered and described in order to understand the evolutionary history of Cortinarius on a global scale.


Atmosphere ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 68
Author(s):  
Arkadiusz M. Tomczyk ◽  
Ewa Bednorz ◽  
Katarzyna Szyga-Pluta

The primary objective of the paper was to characterize the climatic conditions in the winter season in Poland in the years 1966/67–2019/20. The study was based on daily values of minimum (Tmin) and maximum air temperature (Tmax), and daily values of snow cover depth. The study showed an increase in both Tmin and Tmax in winter. The most intensive changes were recorded in north-eastern and northern regions. The coldest winters were recorded in the first half of the analyzed multiannual period, exceptionally cold being winters 1969/70 and 1984/85. The warmest winters occurred in the second half of the analyzed period and among seasons with the highest mean Tmax, particularly winters 2019/20 and 1989/90 stood out. In the study period, a decrease in snow cover depth statistically significant in the majority of stations in Poland was determined, as well as its variability both within the winter season and multiannual.


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