Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 8

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
1

Ant-aphid interaction and territorial dynamics of wood ants

100%
Vepsalainen K., Savolainen R.
Memorabilia Zoologica
|
1994
|
tom 48
251-259
2

Competition hierarchies in ant communities (Hymenoptera, Formicidae)

100%
Pisarski B., Vepsalainen K.
Annales Zoologici
|
1988-1989
|
tom 42
|
nr 13-17
A concept of competition hierarchy among ant species is presented. The hierarchy consists of three main levels, and the species are arranged in the hierarchy on the basis of social organization (mainly forager densities and recruitment efficiencies) of colonies. The concept allows testable predictions on probable and improbable species pairs in local ant species assemblages. Structure of competition hierarchy and positions of a number of North European species in it is reviewed. A schematisized map on minimal distances among nests of species belonging to various levels of the hierarchy is presented. A case study on relations among highest-level, territorial species, is described.
3

Territory size of wood ants (Hymenoptera: Formicidae): a search for limits of existence of Formica polyctena Först., an inherently polygynic and polycalic species

100%
Czechowski W., Vepsalainen K.
Annales Zoologici
|
2009
|
tom 59
|
nr 2
Wood ants are often absent on islands of the Gulf of Finland, even when seemingly suitable habitats are available. Their absence may partially be explained by the lack or rarity of ant species suitable as host during colonisation through temporary parasitism. To search for the limits of living conditions on islands, given colonisation constraints are overcome, we artificially established wood ant colonies on several islands constituting a series from suboptimal to extremely harsh living conditions. The case reported here showed that a barren < 0.2 ha islet, with aphids on its single pine tree the only permanent and relatively rich food source, has allowed the existence of an artificially introduced Formica polyctena Forst, colony for 22 years. The ambient living conditions are probably close to the limit for the species, as evidently the colony does not produce sexual offspring. Thus the sustained existence of the colony is dependent on adoption of fertile gynes originating in colonies that live in more optimal conditions. We suggest that the polygynic social mode of the inherently polycalic F. polyctena is the key for its sustained existence on the islet, as polygyny together with receptivity to new, even alien queens keeps the colony alive in a sink habitat insufficient for production of own sexual offspring.
4

Replacement of species in wood ant colonies artificially established on islands in Southern Finland

100%
Czechowski W., Vepsalainen K.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 4
Wood ants, i.e. species of the subgenus Formica s. str., are known to be temporary social parasites of ants of the subgenus Serviformica For. However, not only Serviformica colonies are used by young wood ant queens to start their own colonies. They are also able to take over colonies, at least queenless ones, of related species of the subgenus Formica s. str. This study followed five experimental colonies of wood ants – three of hybrid Formica aquilonia × F. polyctena, one of F. aquilonia-like form, and one of F. polyctena – artificially planted on islands of the Tvärminne archipelago, S Finland. After some years, the species identity of all colonies was F. polyctena, i.e. four of them had been taken over by heterospecific queens, whose offspring gradually replaced the old workers. These findings, together with already documented existence of hybrids in wood ants, partly explain the interspecific and intracolonial, until recently unaccountable, variability in wood ants of the Formica rufa group, frequently observed in southern Finland.
5

Plezjobioza Formica fusca L. z rudymi mrowkami lesnymi [Hymenoptera, Formicidae]

100%
Czechowski W., Vepsalainen K.
Przegląd Zoologiczny
|
1999
|
tom 43
|
nr 3-4
215-218
6

Formica rufa L. protects indirectly F.fusca L. against raids of F.sanguinea Latr. [Hymenoptera: Formicidae]

100%
Czechowski W., Vepsalainen K.
Annales Zoologici
|
2001
|
tom 51
|
nr 3
By protecting their territory against all territorial ants, Formica rufa L. indirectly protected F. fusca L., nesting within their territory, against F. sanguinea Latr. raids. The permanent costs to F. fusca caused by highly aggressive F. rufa within their territories were outweighed by the benefits obtained by F. rufa’s protection against periodic raids of F. sanguinea. We interprete our findings in the light of the hierarchy competitive framework as follows.
7

Plesiobiosis between Formica fusca L. and Formica aquilonia Yarr. [Hymenoptera, Formicidae]

100%
Czechowski W., Vepsalainen K.
Annales Zoologici
|
1999-2000
|
tom 49
|
nr 1-2
8

Indirect effects in boreal ant assemblages: territorial wood ants protect potential slaves against enslaving ants

81%
Vaananen S., Vepsalainen K., Savolainen R.
Annales Zoologici
|
2010
|
tom 60
|
nr 1
The facultative enslaver Formica sanguinea Latr. uses as slaves F. fusca L. and other species of the subgenus Serviformica For. Earlier observations have shown or suggested that strong territorial wood-ant species, by defending their own territories, interfere with raids by F. sanguinea such that colonies of potential slave species gain protection against raids. At the population level, such protection should be visible as higher nest densities of F. fusca within than outside wood-ant territories, when both areas are within raiding distance of F. sanguinea. Here we tested this hypothesis by mapping nest densities of F. fusca. As expected, nest densities of F. fusca were higher within than outside wood-ant territories. In contrast, nest densities of two aggressive species, Lasius platythorax Seifert and L. niger (L.), unsuitable as slaves, were as expected lower within than outside wood-ant territories. Our results concur with earlier studies based on pitfall trapping, baiting experiments, and in situ observations on raids. The results also show that the positive impact of indirect protection provided by wood ants against raids may outweigh the direct negative impact of wood ants on F. fusca nesting within their territories. We discuss the geographic and habitat cooccurrences of wood ants, enslavers and potential slave species, and coverage of efficient indirect protection of potential slaves against raids.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.