Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Interspecific hybridization in sympatric species of Daphnia inhabiting lakes in northeastern Poland

Brzeziński T., Fronk J., Trzcińska-Danielewicz J., Dawidowicz P.

Oceanological and Hydrobiological Studies

2012

Vol. 41, No. 2

1-6

Populations of three sympatric species (Daphnia cucullata, Daphnia galeata, and Daphnia hyalina (Daphnia longispina complex)) inhabiting three lakes in northeastern Poland (Roś, Mikołajskie, Wigry) were checked for interspecific hybrids. Hybrid Daphnia coexisting with parental individuals were detected in each of the investigated lakes. Several classes of hybrids (F1, F2, backcrosses), including D. cucullata×galeata×hyalina individuals, have been detected. Hybrids constituted a substantial (13%-38%) part of the total abundance of individuals of the D. longispina complex. Deficiency of heterozygotes (hybrids) detected may indicate the existence of barriers for gene flow between the sympatric Daphnia taxa.

Phenotypic plasticity within Daphnia longispina complex : differences between parental and hybrid clones

Pijanowska J., Bernatowicz P., Fronk J.

Polish Journal of Ecology

2007

Vol. 55, nr 4

761-769

The mechanism that enables the coexistence of apparently very similar species is fundamental in understanding the diversity of natural communities. The ranges of reactions of the three Daphnia clones in the presence of toxic compounds and fish kairomones were studied in laboratory. The ranges were based on differences in body length, spine length and fecundity (number of eggs in a brood chamber) during first three reproductions. The ranges of reactions of the three clones differed dramatically. The range of D. galeata and D. hyalina hardly overlapped, while that of a D. galeata x hyalina hybrid clone was significantly broader than the ranges of either parental species. The observed diversity of ranges of reactions probably enables the coexistence of closely related species in the variable environment of natural lakes.