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001-es BibID:BIBFORM042542
Első szerző:Hargitai Rita
Cím:Variation in Plasma Oxidative Status and Testosterone Level in Relation to Egg-Eviction Effort and Age of Brood-Parasitic Common Cuckoo Nestlings / Rita Hargitai, David Costantini, Csaba Moskát, Miklós Bán, Jaime Muriel, Mark E. Hauber
Dátum:2012
ISSN:0010-5422
Megjegyzések:To avoid competition for parental care, brood-parasitic Common Cuckoo (Cuculus canorus)nestlings evict all of the host's eggs and nestlings within a few days after hatching. Little is known about the physiological effects of eviction behavior on the cuckoo nestling's oxidative balance or about age-related variation in plasma oxidative status and testosterone level of developing birds. We examined whwther the cuckoo nestling' plasma oxidative status was related to prior effort in eviction and quantified variation in the level of reactive oxygen metabolites, of nonenzymatic antioxidant capacity, and of testosterone concentration in plasma at various phases of the cuckoo's development. Levels of both reactive oxygen metabolites and antioxidant capacity were greater in older than in younger nestlings, suggesting that younger nestlings effectively counterbalance their increased production of free radicals, whereas, near fledging, levels of reactive oxygen metabolites increase despite improved antioxidant capacity. Possibly, overall energy expenditure increases with age and elevates the production of reactive oxygen species to a rate higher than what the antioxidant system could eliminate. Plasma testosterone level was the highest at nestling's intermediate phase of growth. High levels of testosterone may be required during the period of fastest growth, and when the growth rate levels off near fledging, testosterone levels may also decline. Cuckoo chicks that evicted more host eggs from steeper nests had higher plasma levels of reactive oxygen metabolites shortly after the eviction period, suggesting that eviction is costly in terms of an increased level of oxidative stress.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
antioxidant capacity
brood parasitism
eviction behavior
oxidative stress
plasma testosterone
Élettudományok - Biológiai tudományok
Megjelenés:Condor. - 114 : 4 (2012), p. 782-791. -
További szerzők:Costantini, David Moskát Csaba Bán Miklós (1975-) (biológus) Muriel, Jaime Hauber, Mark E.
Pályázati támogatás:MTA-DE Lendület
MTA
Viselkedésökológiai Kutatócsoport
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2.

001-es BibID:BIBFORM023351
Első szerző:Liker András
Cím:Male badge size predicts dominance against females in House Sparrows1 / András Liker, Zoltán Barta
Dátum:2001
Megjegyzések:We investigated dominance relationships and the use of male badge size as a status signal in a mixed-sex flock of House Sparrows (Passer domesticus). Specifically, we tested whether females differ from males in their fighting behavior or dominance status, and whether badge size predicts dominance and fighting success of males in male-female fights. We found that both sexes were involved frequently in aggressive encounters, and the mean dominance rank of males did not differ from the mean rank of females. Badge size was the only significant predictor of the dominance rank of males, and was a good predictor of their aggressiveness measured as the proportion of fights initiated. On the other hand, female dominance rank was correlated with body weight. In male-female fights, both the proportion of female-initiated aggressive interactions and the proportion of fights won by females decreased with increasing size of the opponent's badge. Large-badged males dominated more females in dyadic interactions than smaller-badged males. These correlational results suggest that male badge size may be used as a signal of dominance status between male and female House Sparrows in winter flocks.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
badge size
dominance
House Sparrow
intersexual aggression
Passer domesticus
social behavior
status signaling
Megjelenés:The Condor. - 103 : 1 (2001), p. 151-157. -
További szerzők:Barta Zoltán (1967-) (biológus, zoológus)
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
DOI
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