A következő címkéjű bejegyzések mutatása: fluctuating asymmetry. Összes bejegyzés megjelenítése
A következő címkéjű bejegyzések mutatása: fluctuating asymmetry. Összes bejegyzés megjelenítése

2014. december 20., szombat

Elek et al. (2014) Community Ecology

Elek Z., Lövei G.L., Bátki M. (2014): No increase in fluctuating asymmetry in ground beetles (Carabidae) as urbanisation progresses. Community Ecology 15: 131-138.

Abstract
Environmental stress can lead to a reduction in developmental homeostasis, which could be reflected in increased variability of morphological traits. Fluctuating asymmetry (FA) is one possible manifestation of such a stress, and is often taken as a proxy for individual fitness. To test the usefulness of FA in morphological traits as an indicator of environmental quality, we studied the effect of urbanisation on FA in ground beetles (Carabidae) near a Danish city. First, we performed a critical examina­tion whether morphological character traits suggested in the literature displayed true fluctuating asymmetry in three common predatory ground beetles, Carabus nemoralis, Nebria brevicollis and Pterostichus melanarius. Eight metrical (length of the second and third antennal segments, elytral length, length of the first tarsus segment, length of the first and second tibiae, length of the proximal and distal spines on the first femurs) and one meristic (the number of spines on the second tibiae) traits were examined. Most of them showed FA but not consistently. Females generally displayed a higher level of FA than males. Finally, we examined the changes in the level of FA in bilateral morphological traits along an urbanisation gradient (forest - suburban forest - forest fragments in urban park) to test whether environmental stress created by urbanisation is reflected in FA. Ground beetles common along a Danish urbanisation gradient did not seem to indicate differences in habitat quality by their level of FA.

Keywords
Developmental instability, Fluctuating asymmetry, Ground beetles, Urbanization

2012. november 29., csütörtök

Plaiasu et al. (2012) Acta Zoologica Academiae Scientiarum Hungaricae


Abstract
Hybridization can occur under natural conditions among well-differentiated species and may affect the developmental stability of hybrids. In the present study, we investigated the effect of interspecific hybridization between Bombina bombina and B. variegata on fluctuating asymmetry (FA) of forelimb, femur, tibia and foot. The hybrids did not show higher levels of FA compared to the parental populations for either investigated traits. This suggested that the effect of hybridization on FA in the analyzed traits is negligible or overwhelmed by other factors. A significantly increased FA was found in the B. bombina populations when compared to B. variegata, which can be attributed to low pressure of natural selection in these populations.


Keywords
interspecific hybridization, Bombina, fluctuating asymmetry