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452. Masai Mara. I. Jedna z legend africké přírody
- Creator:
- Miloš Anděra
- Format:
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, savci, národní parky, ekologie, mammals, national parks, ecology, Afrika, Africa, 2, and 59
- Language:
- Czech
- Description:
- Keňská národní rezervace Masai Mara (též Maasai Mara) o rozloze 1 510 km2 se nachází ve Velké příkopové propadlině a přímo navazuje na národní park Serengeti v severní Tanzanii. Většinu jejího území pokrývají mírně zvlněné travnaté savany živené četnými srážkami v několika obdobích dešťů od listopadu do dubna. Pouze území v blízkém okolí řeky Mary a jejích přítoků jsou zalesněná. Rezervace je celosvětově proslulá mimořádně početnými migrujícími stády velkých kopytníků a jejich predátorů. V posledních desetiletích však populace některých druhů výrazně ubývají, za hlavní rizikové faktory se považuje rozšiřující se pastva skotu a nekontrolovaný rozvoj cestovního ruchu., Kenya’s Masai Mara National Reserve, covering an area of 1,510 km2, is situated in the Rift Valley with Tanzania’s Serengeti Plains running along its southern end. Most of the reserve is made up of hilly grassland, fed by plentiful rain, especially during the wet months between November and April. Only the areas near the Mara river and its tributaries are forested. The reserve is famous for its exceptional migrating populations of larger ungulates and its predators. However, the last decades have seen a considerable decrease in abundance of some species - the main causes are expanding livestock grazing and uncontrolled development of tourism., and Miloš Anděra.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
453. Masai Mara. II. Dvojí velké stěhování
- Creator:
- Miloš Anděra
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, zoologie, savci, národní parky, zoology, mammals, national parks, Keňa, Kenya, Národní park Serengeti (Tanzanie), Serengeti National Park (Tanzania), 2, and 59
- Language:
- Czech
- Description:
- Rezervaci Masai Mara proslavila především každoroční masová migrace pakoňů žíhaných (Connochaetes taurinus) a dalších kopytníků ze Serengeti (Tanzanie). Primární příčinou stěhování je střídání srážkového cyklu v rovníkové východní Africe a s tím související nabídka zelené potravy. Je ovšem obtížné určit přesný začátek či konec velkého stěhování – jde o neustále běžící cyklus, jehož jednotlivé fáze přecházejí plynule jedna v druhou. Navíc načasování migrací se rok od roku liší podle počasí i v řádu měsíců. Celá migrační trasa o délce zhruba 800 km má podobu nepravidelného oválu. Pohyb mnohatisícových až milionových stád přitahuje množství turistů z celého světa (druhé stěhování)., The Masai Mara reservation is famous for its annual mass migration of the Wildebeest (Connochaetes taurinus) and other hoofed animals from the Serengeti (Tanzania). Its primary cause is the changing precipitation cycle in equatorial east Africa, and the related supply of green food. It is difficult to determine exactly the beginning and the end of the Great Migration – it is a constantly running cycle, and its timing varies from year to year depending on weather conditions over a span of months. The entire route has a length of about 800 km. The movement of herds with hundreds of thousands to millions of animals attracts an ever-increasing number of tourists from around the world annually (the second migration)., and Miloš Anděra.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
454. Mating advantage of short-winged over long-winged adult males in the cricket Velarifictorus ornatus (Orthoptera: Gryllidae)
- Creator:
- Zhao, Lv-Quan, Chai, Huai-Lin, Wu, Hong-Jun, and Zhu, Dao-Hong
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, rovnokřídlí, cvrčkovití, Orthoptera, Gryllidae, Velarifictorus ornatus, mating competition, sing song, trade-off, wing polymorphism, 2, and 59
- Language:
- English
- Description:
- The trade-off between flight capability and reproduction is well known in adult males of insects with wing dimorphism but the reproductive advantage of short-winged (SW) males over long-winged (LW) males appears to vary across insect taxa. In the present study, we determined the difference in the mating ability of SW and LW males of Velarifictorus ornatus (Orthoptera: Gryllidae) in order to evaluate whether the SW male morph has a reproductive advantage. We found that the choice of a mate depended on the female. Compared with LW males, SW males had an obvious mating advantage when both SW and LW males courted females simultaneously, and that dealation significantly enhanced the mating ability of LW males. Losing the ability to produce songs reduced the mating advantage of SW males, thereby indicating that the greater mating advantage of SW males was related to the attractiveness of the song. In addition, the difference in the mating ability of LW and SW males was not related to body size or age. These results indicate that SW males of V. ornatus have a mating advantage over their LW counterparts because their underdeveloped flight muscles allow them to devote more resources to reproduction., Lv-Quan Zhao, Huai-Lin Chai, Hong-Jun Wu, Dao-Hong ZhuU., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
455. Mating alters the rate of development of ovarioles in the ladybird, Propylea dissecta (Coleoptera: Coccinellidae)
- Creator:
- Shahid, Mhd, Siddiqui, Arshi, Omkar, and Mishra, Geetanjali
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, věk, beetles, Coccinellidae, age, Coleoptera, Propylea dissecta, mating status, ovariole development, egg maturation, egg load, 2, and 59
- Language:
- English
- Description:
- The influence of female mating status on ovarian development of the ladybird, Propylea dissecta (Mulsant) (Coleoptera: Coccinellidae), was investigated under laboratory conditions. We assessed the extent to which ovariole development was affected by mating and for that we initially created a base line by observing age specific ovariole development. Results show that the number of follicles in each ovariole increased with the age of both virgin and mated females up to the age of 3 days, thereafter, no increase in number of follicles was recorded. Ovariole width also increased with age in both virgin and mated females up to 4 days, thereafter, no increase in ovariole width was recorded. The ovariole width of mated females was significantly greater than that of virgin females. Egg maturation and the egg load started to increase at the age of 8 days in virgin females. Thereafter, it increased with increase in female age. While in mated females, immature eggs were recorded in their ovarioles from the age of 1 to 2 days. In mated females, however, the increase in the number of mature eggs per ovariole and egg load started when they were 3 days old. Egg load continuously increased with increasing female age., Mhd Shahid, Arshi Siddiqui, Omkar, Geetanjali Mishra., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
456. Medvěd hnědý, jeho vyhubení a návrat do naší přírody. 1
- Creator:
- Jan Andreska
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, medvěd hnědý, vyhubení, Česko, 2, and 59
- Language:
- Czech
- Description:
- Detailed knowledge of the circumstances behind the extermination of particular animal species is a key premise for their eventual return, reintroduction and ongoing preservation. Data on the presence of the Brown Bear (Ursus arctos) in the Czech landscape are usually limited to simple entries about the day and place where the last specimens in particular (usually mountainous) regions were slain. Demand for more precise data, especially regarding the last documented presence of bear cubs, has emerged in respect of the recently discovered ability of bears to migrate over long distances. The newly collected data allowed the author to present amuch more complete historical view of the process of extermination of the Brown Bear in the Czech territory. and Jan Andreska.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
457. Medvěd hnědý, jeho vyhubení a návrat do naší přírody. II
- Creator:
- Jan Andreska
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, medvěd hnědý, Česko, 2, and 59
- Language:
- Czech
- Description:
- The prolonged survival of the Brown Bear (Ursus arctos) population in the Bohemian Forest was largely possible due to the protec tion of this animal, which was considered a rare and desirable trophy. Consequently the bear was able to survive in the Bohemian Forest for a hundred years longer than in the Ore Mountains. Isolated populations in the Sudetes survived in Moravia, and the last specimens were hunted down in the 1740s. Bears hunted down during the 19th century in the Beskydy Mts. can almost certainly be considered casual migrants from the Slovak part of this mountain range. The return of bears to the territory of Moravia and Silesia corresponds with the consolidation of the Slovak population due to the protection introduced in 1932. and Jan Andreska.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
458. Měkkýši lomů v Českém krasu
- Creator:
- Kocurková, Alena and Lucie Juřičková
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, měkkýši, lomy, Český kras (Česko), 2, and 59
- Language:
- Czech
- Description:
- Large amounts of abandoned limestone quarries in the Bohemian Karst provide a great opportunity to study different stages of spontaneous succession simulta - neously. Molluscs are a suitable model group for this study –many land snail species including the rare ones occur in these quarries. Because of the large variability of habitats, quarries abandoned for around 60 years have higher species diversity. and Alena Kocurková, Lucie Juřičková.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
459. Meta temnostní - pavouk roku 2012
- Creator:
- Milan Řezáč
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, pavouci, křižákovití, 2, and 59
- Language:
- Czech
- Description:
- The elected large cave spider Meta me nar - di occurs throughout the Palaearctic re - gion. In Central Europe, it is usually found in upland regions, and is particularly common in karst areas. The spider lives in subterranean caves, cellars, mineshafts and stone runs. and Milan Řezáč.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
460. Metagenomic survey of bacteria associated with the invasive ladybird Harmonia axyridis (Coleoptera: Coccinellidae)
- Creator:
- Dudek, Krzysztof, Humińska, Kinga, Wojciechowicz, Jacek, and Piotr Tryjanowski
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, slunéčko východní, beetles, Coccinellidae, Harmonia axyridis, Coleoptera, microbiota, bacteria community, 16s RNA, insect symbionts, 2, and 59
- Language:
- English
- Description:
- The Asian ladybird Harmonia axyridis is an invasive insect in Europe and the Americas and is a great threat to the environment in invaded areas. The situation is exacerbated by the fact that non native species are resistant to many groups of parasites that attack native insects. However, very little is known about the complex microbial community associated with this insect. This study based on sequencing 16S rRNA genes in extracted metagenomic DNA is the first research on the bacterial flora associated with H. axyridis. Lady beetles were collected during hibernation from wind turbines in Poland. A mean ± SD of 114 ± 35 species of bacteria were identified. The dominant phyla of bacteria recorded associated with H. axyridis were Actinobacteria, Proteobacteria, Firmicutes and Bacteroidetes. Representatives of these phyla are common in the environment, e.g. in the soil, and are often identified as the dominant bacteria associated with arthropods. We also identified animal pathogenic bacteria, such as Burkholderia, Rhodococcus, Chlamydiae and Anaplasmataceae spp. (Neorickettsia helminthoeca and Ehrlichia ovina). We also identified Wolbachia pipientis in a single beetle. This bacterium is a causative agent of reproductive alterations in arthropods. These results support the enemy release hypothesis in the case of this ladybird invasion. Pathogenic bacteria were recorded in only a few samples. Moreover, male-killing bacteria such as Spiroplasma spp., Wolbachia spp. and Rickettsia spp. were only recorded in single insects so they cannot be responsible for the observed alterations in the sex-ratio of the ladybird population studied., Krzysztof Dudek, Kinga Humińska, Jacek Wojciechowicz, Piotr Tryjanowski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public