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001-es BibID:	BIBFORM018141
Első szerző:	Magyari Enikő (biológus)
Cím:	Population dynamics and genetic changes of Picea abies in the South Carpathians revealed by pollen and ancient DNA analyses / Enikő K Magyari, Ágnes Major, Miklós Bálint, Judit Nédli, Mihály Braun, István Rácz, Laura Parducci
Dátum:	2011
ISSN:	1471-2148
Megjegyzések:	Background Studies on allele length polymorphism designate several glacial refugia for Norway spruce (Picea abies) in the South Carpathian Mountains, but infer only limited expansion from these refugia after the last glaciation. To better understand the genetic dynamics of a South Carpathian spruce lineage, we compared ancient DNA from 10,700 and 11,000-year-old spruce pollen and macrofossils retrieved from Holocene lake sediment in the Retezat Mountains with DNA extracted from extant material from the same site. We used eight primer pairs that amplified short and variable regions of the spruce cpDNA. In addition, from the same lake sediment we obtained a 15,000-years-long pollen accumulation rate (PAR) record for spruce that helped us to infer changes in population size at this site. Results We obtained successful amplifications for Norway spruce from 17 out of 462 pollen grains tested, while the macrofossil material provided 22 DNA sequences. Two fossil sequences were found to be unique to the ancient material. Population genetic statistics showed higher genetic diversity in the ancient individuals compared to the extant ones. Similarly, statistically significant Ks and Kst values showed a considerable level of differentiation between extant and ancient populations at the same loci. Lateglacial and Holocene PAR values suggested that population size of the ancient population was small, in the range of 1/10 or 1/5 of the extant population. PAR analysis also detected two periods of rapid population growths (from ca. 11,100 and 3900 calibrated years before present (cal yr BP)) and three bottlenecks (around 9180, 7200 and 2200 cal yr BP), likely triggered by climatic change and human impact. Conclusion Our results suggest that the paternal lineages observed today in the Retezat Mountains persisted at this site at least since the early Holocene. Combination of the results from the genetic and the PAR analyses furthermore suggests that the higher level of genetic variation found in the ancient populations and the loss of ancient allele types detected in the extant individuals were likely due to the repeated bottlenecks during the Holocene; however our limited sample size did not allow us to exclude sampling effect. This study demonstrates how past population size changes inferred from PAR records can be efficiently used in combination with ancient DNA studies. The joint application of palaeoecological and population genetics analyses proved to be a powerful tool to understand the influence of past population demographic changes on the haplotype diversity and genetic composition of forest tree species.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	BMC Evolutionary Biology. - 11 : 66 (2011), p. 1-16. -
További szerzők:	Major Ágnes Bálint Miklós Nédli Judit (1980- ) (biológus) Braun Mihály (1966-) (vegyész, analitikus) Rácz István András (1949-) (biológus) Parel, Serge P.
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM081452
035-os BibID:	(cikkazonosító)219
Első szerző:	Ouyang, Jenny Q.
Cím:	Weathering the storm : parental effort and experimental manipulation of stress hormones predict brood survival / J. Q. Ouyang, Á. Z. Lendvai, R. Dakin, A. D. Domalik, V. J. Fasanello, B. G. Vassallo, M. F. Haussmann, I. T. Moore. F. Bonier
Dátum:	2015
ISSN:	1471-2148
Megjegyzések:	Background Unpredictable and inclement weather is increasing in strength and frequency, challenging organisms to respond adaptively. One way in which animals respond to environmental challenges is through the secretion of glucocorticoid stress hormones. These hormones mobilize energy stores and suppress non-essential physiological and behavioral processes until the challenge passes. To investigate the effects of glucocorticoids on reproductive decisions, we experimentally increased corticosterone levels (the primary glucocorticoid in birds) in free-living female tree swallows, Tachycineta bicolor, during the chick-rearing stage. Due to an unprecedented cold and wet breeding season, 90 % of the nests in our study population failed, which created a unique opportunity to test how challenging environmental conditions interact with the physiological mechanisms underlying life-history trade-offs. Results We found that exogenous corticosterone influenced the regulation of parental decisions in a context-dependent manner. Control and corticosterone-treated females had similar brood failure rates under unfavorable conditions (cold and rainy weather), but corticosterone treatment hastened brood mortality under more favorable conditions. Higher female nest provisioning rates prior to implantation were associated with increased probability of brood survival for treatment and control groups. However, higher pre-treatment male provisioning rates were associated with increased survival probability in the control group, but not the corticosterone-treated group. Conclusions These findings reveal complex interactions between weather, female physiological state, and partner parental investment. Our results also demonstrate a causal relationship between corticosterone concentrations and individual reproductive behaviors, and point to a mechanism for why naturally disturbed populations, which experience multiple stressors, could be more susceptible and unable to respond adaptively to changing environmental conditions.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Corticosterone Stress Reproduction Tree swallow Tachycineta bicolor Biparental care Inclement weather Hormone implant
Megjelenés:	BMC Evolutionary Biology. - 15 : 1 (2015), p. 1-8. -
További szerzők:	Lendvai Ádám Zoltán (1977-) (biológus) Dakin, Roslyn Domalik, Alice D. Fasanello, Vincent J. Vassallo, B. G. Haussmann, Mark F. Moore, Ignacio T. Bonier, Fraces
Pályázati támogatás:	OTKA K113108 OTKA
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