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Start Over Rights http://creativecommons.org/licenses/by-nc-sa/4.0/ Subject 59 Type články Harvested from CDK

291. Vztahy rostlin a opylovačů na louce aneb nejen botanici určují rostliny

Creator:
Janovský, Zdeněk
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, rostliny, opylovači, rostlinná společenstva, 2, and 59
Language:
Czech
Description:
The honey bee is usually thought of as a key pollinator in cultural landscapes. Our results evidence that although it may be the most abundant, its importance is lower compared to hoverflies and bumblebees both in terms of the pollinated plant species number and the spectrum of vegetation types covered. The broad spectrum of hoverfly diets suggests the cause of their high importance as pollinators. and Zdeněk Janovský.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

292. Warp-speed adaptation to novel hosts after 300 generations of enforced dietary specialisation in the seed beetle Callosobruchus maculatus (Coleoptera: Chrysomelidae: Bruchinae)

Creator:
Price, Thomas N., Leonard, Aoife, and Lancaster, Lesley T.
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, brouci, mandelinkovití, beetles, Chrysomelidae, Coleoptera, Bruchinae, Callosobruchus maculatus, emerging crop pests, host shifts, genetic variation, adaptation trajectory, evolvability, experimental evolution, quasi-natural selection, heritability, 2, and 59
Language:
English
Description:
Herbivorous insects are often highly specialised, likely due to trade-offs in fitness on alternative host species. However, some pest insects are extremely adaptable and readily adopt novel hosts, sometimes causing rapid expansion of their host range as they spread from their original host and geographic origin. The genetic basis of this phenomenon is poorly understood, limiting our ability to predict or mitigate global insect pest outbreaks. We investigated the trajectory of early adaptation to novel hosts in a regionally-specialised global crop pest species (the cowpea seed beetle Callosobruchus maculatus). After experimentally-enforced dietary specialisation for nearly 300 generations, we measured changes in fitness over the first 5 generations of adaptation to 6 novel hosts. Of these, C. maculatus reproduced successfully on all but one, with reduced fitness observed on three hosts in the first generation. Loss of fitness was followed by very rapid, decelerating increases in fitness over the first 1-5 generations, resulting in comparable levels of population fitness to that observed on the original host after 5 generations. Heritability of fitness on novel hosts was high. Adaptation occurred primarily via changes in behavioural and phenological traits, and never via changes in offspring survival to adulthood, despite high heritability for this trait. These results suggest that C. maculatus possesses ample additive genetic variation for very rapid host shifts, despite a prolonged period of enforced specialization, and also suggest that some previously-inferred environmental maternal effects on host use may in part actually represent (rapidly) evolved changes. We highlight the need to examine in more detail the genetic architecture facilitating retention of high additive genetic variation for host shifts in extremely adaptable global crop pests., Thomas N. Price, Aoife Leonard, Lesley T. Lancaster., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

293. White plant shoots, wax-producing insects and other white structures made by arthropods: a mimicry complex?

Creator:
Yamazaki, Kazuo
Format:
print, počítač, and online zdroj
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, vosky, pavouci, waxes, spiders, plant mimicry, anti-herbivore defence, cocoon, entomopathogenic fungus, spider egg sac, spittlebug froth, trichome, 2, and 59
Language:
English
Description:
Many insects masquerade as parts of plants, such as bark or leaves, or mimic poisonous organisms in order to defend themselves against predators. However, recent studies indicate that plants may mimic insects and other arthropods to deter herbivores. Here, I report visually similar white structures of plants and arthropods in Japan and suggest they are part of a mimicry complex. Young shoots covered with white trichomes or waxy substances may mimic wax-producing insects, such as woolly aphids, coccids and caterpillars, potentially resulting in reduced herbivory. Since wax-producing insects would reduce plant quality and quantity, be distasteful and attract natural enemies, herbivorous insects and mammals may avoid such white shoots. Furthermore, fungus-infected insects, gregarious braconid cocoons, spider egg sacs and froth made by froghopper nymphs or blasticotomid sawfly larvae are also conspicuously white and impose risks for herbivorous insects. Thus, these white structures may be mimicry models for white shoots and are likely to be part of a defensive mimicry complex. Although this study focuses on defence against herbivores, there are simultaneous physiological roles for white colouration that will not be discussed in depth here., Kazuo Yamazaki., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

295. Za savci na poloostrov Valdés

Creator:
Suchomel, Josef
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, savci, Valdés (Argentina : poloostrov), 2, and 59
Language:
Czech
Description:
This review article describes the phylogeny of sheep in genus Ovis. Individual species of sheep, their geographic distribu tion and nomenclature are presented in the light of the latest taxonomic revision. The current understanding of sheep domestication process is also described. Numerous gaps in our knowledge of this important and only seemingly well-known group of ruminants are mentioned. and Josef Suchomel.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

296. Záhadné rozmnožování a výživa papouška kakapa sovího

Creator:
Tumová, Petra
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, ptáci, životní prostředí, ekologie, birds, environment, ecology, 2, and 59
Language:
Czech
Description:
Boj o záchranu jednoho z nejvzácnějších a nejunikátnějších ptačích druhů - Kakapa sovího (Strigops habroptilus) - trvá už několik desítek let. Veškeré snahy dlouhou dobu selhávaly, než vědci odhalili, jak úzce záhadné rozmnožování tohoto druhu souvisí s jeho výživou. Od roku 2000 se tak podařilo populaci více než zdvojnásobit. Za zachráněný však druh bude považován až ve chvíli, kdy dokáže přežít a rozmnožovat se bez pomoci člověka. Záchrana kakapa sovího je běh na dlouhou trať, čím víc ale o jeho biologii víme, tím větší máme naději, že se to podaří., The endeavour to save one of the rarest and most unique species of birds - Kakapo (Strigops habroptilus) - has been going on for decades. All efforts were unsuccessful until the scientists discovered how closely is the reproduction of this species related to its diet. Since the year of 2000 the population has doubled its original. However, the recovery of Kakapo populations is a long process, the species can only be considered salvaged when it is able to reproduce without human assistance., and Petra Tumová.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

298. Zápřednice jedovatá - opravdu nejjedovatější pavouk České republiky?

Creator:
Košulič, Ondřej, Korba, Jan, and Dolanský, Jan
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, pavouci, jedovatí živočichové, Česko, 2, and 59
Language:
Czech
Description:
The Yellow Sack Spider (Cheiracanthium punctorium) is a well-known species native to the Czech Republic. Several reports of its painful bite have gained much publicity. The species was considered to be very rare until the end of the 20th century. We provide information on the distribution, spread and ecology of this spider in the Czech Republic. Several cases of biting and its subsequent symptoms are described, and the toxicity of the spider is discussed. and Ondřej Košulič, Jan Korba, Jan Dolanský.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

299. Zateplování budov a ptáci

Creator:
Marta Heroldová and Jan Zejda
Format:
print
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, ptáci, zateplování budov, birds, heat cladding, Královo Pole (Brno, Česko), Královo Pole (Brno, Czechia), 2, and 59
Language:
Czech
Description:
V uplynulém roce (2012) máme doloženy poznatky o poškozování zateplených budov ptáky v městské části Královo Pole v Brně. Na lokalitě jsme zjistili přítomnost strakapouda velkého (Dendrocopos major), strakapouda malého (D. minor) a žluny zelené (Picus viridis). Půl roku po ukončení rekonstrukčních prací se zájem těchto tří druhů šplhavců soustředil na omítky a obložení pláště domů polystyrenem, především v prostoru těsně pod střešní římsou. Pozornost jsme soustředili na činnost největšího druhu – žluny zelené (rozměry jedince byly 30–33 cm). V článku je podrobně popsán průběh činnosti dlabání dutiny., The European Green Woodpecker (Picus viridis) excavated holes under the eaves of roof of the polystyrene-clad houses. Detailed observation in late autumn revealed a cavity with a two-litre volume hollowed out over five hours., and Marta Heroldová, Jan Zejda.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

300. Ze života potápek na našich rybnících. 1

Creator:
Sychra, Jan
Format:
print
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, ptáci, potápky, rybníky, Česko, 2, and 59
Language:
Czech
Description:
The order grebes (Podicipediformes) is an archaic group of birds, morphologically and ecologically well adapted to the aquatic life style, including breeding in floating nests in the littoral zone of water bodies. Four grebe species are breeding in fishponds in the Czech republic. Annually during the breeding season, these birds have to overcome many problems to successfully breed. In the incubation period, the most important mission for parents is to protect the eggs from predation. and Jan Sychra.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

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