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182. Long-term partitioning of space between two territorial species of ants (Hymenoptera: Formicidae) and their effect on subordinate species

Creator:
Wojciech Czechowski, Markó, Bálint, Radchenko, Alexander, and Slipinski, Piotr
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Formica polyctena, Hymenoptera, Formicidae, ants, Lasius fuliginosus, Myrmica, competition, conflicts, interspecific hierarchy, territoriality, 2, and 59
Language:
English
Description:
Competition is a major force organizing ant communities and results in co-occurring species evolving different strategies for foraging and use of space. Territorial species, as top dominants exclude each other, while shaping the local ant communities both qualitatively and quantitatively. In this study we examined how two territorial species, Formica polyctena and Lasius fuliginosus, can coexist in adjacent territories over long periods of time, and whether they affect co-occurring species of ants in different ways. Field observations in the absence and in the presence of baits were carried out around a L. fuliginosus nest complex surrounded by a polydomous F. polyctena colony in S Finland in 2007–2009. Both species controlled their territories, but were affected by changes in the abundance of the other species and the distance from L. fuliginosus’ main nest. They did not have the same effect on the subordinate species in the absence of baits, but the abundance of Myrmica spp. recorded at baits was negatively affected by both of the territorial species. The preferences of the different species for the artificial food sources differed: L. fuliginosus and F. polyctena preferred tuna to honey and Myrmica spp. honey to tuna. More individuals of the subordinate species were recorded in the territory of F. polyctena than of L. fuliginosus, although conflicts with this territorial species were also recorded. During the three years of the study almost no overlaps in the territories of the two territorial species were recorded, and there were mostly minor shifts in the boundaries of the territories. Differences between the two territorial species in their use of space and competitive effects ensured their coexistence at this particular site in Finland., Wojciech Czechowski ... [et al.]., and Obsahuje seznam literatury
Rights:
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183. Lstivá, prostopášná a bojechtivá koroptev podle Aristotela a raněkřesťanského Physiologu /

Creator:
Šedinová, Hana
Type:
studie
Subject:
Zoologie, Aristotelés,, Thomas Cantipratensis,, zoologie, zvířata, literatura středověká, literatura antická, prameny písemné, encyklopedie, literatura latinská, starověké Řecko, Kréta, světové dějiny středověku (do r. 1492), literatura, spisovatelé, české země 1306-1526, and vědy o živé přírodě
Language:
Czech
Description:
Cunning, lustful and truculent partridge according to Aristotle and early Christian Physiologus.
Rights:
unknown

185. Luňáci, jejich variabilita a hybridizace

Creator:
Ivan Literák, Matušík, Hynek, and Rác, Petr
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, ptáci, birds, 2, and 59
Language:
Czech
Description:
Luňáci rodu Milvus jsou v současné době objektem studia ornitologických taxonomů (v současnosti se rozlišují čtyři druhy), věnuje se jim pozornost z hlediska evoluční historie, udivováni jsme poznatky z jejich sociálního života a velké úsilí je zaměřeno na jejich ochranu. Překvapivě početné jsou případy mezidruhové hybridizace mezi sympatricky (na stejném území) se vyskytujícími luňáky červenými (M. milvus) a luňáky hnědými (M. migrans). V článku je přiblížen aktuální pohled na taxonomii luňáků v globálním kontextu a detailně popíšeme průběh hnízdění smíšených párů luňáka červeného a luňáka hnědého, které se nám poprvé v přírodě podařilo zaznamenat v letech 1995 a 1996 na Slovensku a r. 2013 také v České republice., At present, four valid species are recognized within the genus Milvus. Red Kites (M. mil­vus) and Black Kites (M. migrans migrans) occur sympatrically in Slovakia and the Czech Republic. One mixed pair of kites (a Red Kite female and Black Kite male) nested successfully in Slovakia in 1995 and 1996 (with three and two young, re­spectively). Another mixed pair of kites (a Red Kite female and Black Kite male) nested successfully in the Czech Republic in 2013. Two young fledged from the nest, the third one was killed by a Goshawk (Accipiter gentilis) during the nesting period. These reports represent the first cases of inter-specific hybridization of kites in these two countries. Moreover, an indication of cooperative nesting was observed in the Czech Republic., Ivan Literát, Hynek Matušík, Peter Rác., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

186. Malé cichlidy z Nového světa

Creator:
Jaroslav Eliáš
Format:
print
Type:
article, články, journal articles, model:article, and TEXT
Subject:
Zoologie, zoologie, ryby, akvaristika, zoology, fishes, aquaristics, 2, and 59
Language:
Czech
Description:
Chovu malých jihoamerických cichlid rodů Laetacara a Nannacara se mohou věnovat i akvaristé, kteří své zálibě nemohou vyčlenit ve svém domově příliš velký prostor. Velkoryse pojaté akvaristické zázemí není v tomto případu nezbytné. Tyto rybky se starají o své potomstvo velmi starostlivě, takže lze při rozmnožování pozorovat různé projevy rodičovské péče., South American cichlids of the genera Laetacara and Nannacara can be bred also by aquarists without an elaborate aquarium equipment. These little fish look after their offspring very carefully, so various displays of parent care can be observed., and Jaroslav Eliáš.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

187. Male mandible trimorphism in the stag beetle Dorcus rectus (Coleoptera: Lucanidae)

Creator:
Iguchi, Yutaka
Type:
article, články, model:article, and TEXT
Subject:
Zoologie, zoologie, entomologie, Lucanidae, Dorcus rectus, stag beetle, mandible, trimorphism, scaling relationship, discontinuous model, 2, and 59
Language:
English
Description:
Males in many beetles show horn or mandible dimorphism. The stag beetle Dorcus rectus was assumed to have dimorphic males, but in this species there are not two but three visually distinct mandibular phenotypes. The aim of this study is to determine if the three phenotypes represent an allometric trimorphism in this species by studying the scaling relationship between body length and mandible length in 148 adult males and 31 adult females. The relationship was fitted using the following four statistical models; a simple line, a logistic curve, a continuous segmented line and a discontinuous line. The best-fitting model for the males was a discontinuous line with two break points and that for the females a simple line. The male data was also well fitted by a logistic curve. The discontinuous linear model divided the males into three groups that were in good agreement with the three phenotypes. These results suggest that a subtle allometric trimorphism possibly exists in males of this species. Small males of this species have no distinct teeth on their mandibles, whereas small males of D. striatipennis and D. curvidens, which are closely related to D. rectus, have a pair of distinct teeth on their mandibles. The phylogenetic relationship of these Dorcus species suggests that the trimorphism in D. rectus may have arisen through the loss of teeth in small males., Yutaka Iguchi., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

189. 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

190. Metabolic neurohormones: release, signal transduction and physiological responses of adipokinetic hormones in insects

Creator:
Van Der Horst, Dick J., Van Marrewijk, Wil J. A., Vullings, Henk G. B., and Diederen, Jacques H. B.
Format:
print, text, and regular print
Type:
article, bibliography, model:article, and TEXT
Subject:
zoologie, entomologie, hmyz, Locusta migratoria, metabolismus, metabolické neurohormony, adipokinetické hormony, biosyntéza, vylučování, přenos signálu, mechanismus přenosu, 595.2/.7, and 591.1
Language:
English
Description:
In view of the extremely high metabolic rates involved, insect flight offers a fascinating model system for studying metabolism during exercise, including its regulation by metabolic neurohormones. In our laboratory the African migratory locust, Locusta migratoria, well-known for its long-distance flights, is used as an internationally recognized model insect. The insect is mass-reared under controlled conditions; its size permits convenient handling in vivo and in vitro, while flight activity can be easily evoked. In addition, research on this pest insect may be of economical importance. A survey of the energy metabolism during locust flight is presented in Fig. 1. Flight activity stimulates the neurosecretory adipokinetic cells in the glandular lobes of the corpus cardiacum, a neuroendocrine gland connected with the insect brain, to release peptide neurohormones, the adipokinetic hormones (AKHs). The target for these hormones is the fat body. Via signal transduction processes, the action of the hormones ultimately results in the mobilization of both carbohydrate and lipid reserves as fuels for flight. Carbohydrate (trehalose) is mobilized from glycogen reserves, implying hormonal activation of the key enzyme, fat body glycogen phosphorylase, by phosphorylation. Similarly, on the lipid side, sn-1,2-diacylglycerol (DAG) is mobilized from stored triacylglycerol (TAG), by hormonal activation of the fat body TAG lipase. The carbohydrate and lipid substrates are transported in the hemolymph to the contracting flight muscles. Carbohydrate provides most of the energy for the initial period of flight, whereas at a later stage, lipid substrate in the blood is increased and gradually takes over. The transport of DAG requires specific lipoprotein carriers (lipophorins) which differ in several respects from the lipoproteins in mammals, and act as a lipid shuttle. This review is focused on three interrelated topics, covering recent data on the biosynthesis and release of the AKHs, their signal transduction mechanisms in the fat body cells, and the changes in the lipophorin system induced by the AKHs during flight., Dick J. Van Der Horst, Wil J.A. Van Marrewijk, Henk G.B. Vullings, Jacques H.B. Diederen, and Lit
Rights:
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