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001-es BibID:BIBFORM096003
035-os BibID:(Scopus)84999027902 (WOS)000396964700012
Első szerző:Tökölyi Jácint (biológus)
Cím:Resource allocation and post-reproductive degeneration in the freshwater cnidarian Hydra oligactis (Pallas, 1766) / Tökölyi Jácint, Ősz Zsófia, Sebestyén Flóra, Barta Zoltán
Dátum:2017
ISSN:0944-2006
Megjegyzések:Freshwater hydra are among the few animal groups that show negligible senescence and can maintain high survival and reproduction rates when kept under stable conditions in the laboratory. Yet, one species of Hydra (H. oligactis) undergoes a senescence-like process in which polyps degenerate and die after sexual reproduction. The ultimate factors responsible for this phenomenon are unclear. High mortality in reproducing animals could be the consequence of increased allocation of resources to reproduction at the expense of somatic maintenance. This hypothesis predicts that patterns of reproduction and survival are influenced by resource availability. To test this prediction we investigated survival and reproduction at different levels of food availability in 10 lineages of H. oligactis derived from a single Hungarian population. Sexual reproduction was accompanied by reduced survival, but a substantial proportion of animals regenerated after sexual reproduction and continued reproducing asexually. Polyps belonging to different lineages showed differences in their propensity to initiate sexual reproduction, gonad number and survival rate. Food availability significantly affected fecundity (number of eggs or testes produced), with the largest number of gonads being produced by animals kept on a high food regime. On the other hand, survival rate was not affected by the amount of food. These results show that survival is conserved at the expense of reproduction in this population when food is low. It remains a question still to be answered why survival is prioritized over reproduction in this population.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Cnidaria
Food availability
Life history
Senescence
Survival/reproduction trade-offs
Megjelenés:Zoology. - 120 (2017), p. 110-116. -
További szerzők:Ősz Zsófia Sebestyén Flóra (1993-) (biológus) Barta Zoltán (1967-) (biológus, zoológus)
Pályázati támogatás:NTP-EFÖ-P-15
Egyéb
János Bolyai Research Scholarship of the Hungarian Academy of Sciences
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2.

001-es BibID:BIBFORM066149
035-os BibID:(Scopus)84952637768 (WoS)000367196900009
Első szerző:Tökölyi Jácint (biológus)
Cím:Effects of food availability on asexual reproduction and stress tolerance along the fast-slow life history continuum in freshwater hydra (Cnidaria: Hydrozoa) / Jácint Tökölyi, Flóra Bradács, Nikolett Hóka, Noémi Kozma, Máté Miklós, Orsolya Mucza, Kinga Lénárt, Zsófia Ősz, Flóra Sebestyén, Zoltán Barta
Dátum:2015
ISSN:0018-8158
Megjegyzések:Life history theory predicts that reproduction and somatic maintenance are negatively related, but the strength of this relationship is expected to depend on food availability. In this study, we investigated asexual reproduction (budding rate) and oxidative stress tolerance as two opposing facets of life history trade-offs in 17 strains of five freshwater hydra species under experimentally simulated low, medium, and high food availability. Stress tolerance was quantified by exposing animals to exogenous H2O2, which mimics reactive oxygen species arising in vivo. The five species differed in life history traits (low budding rate and high stress tolerance in Hydra vulgaris and H. circumcincta and the opposite in H. oligactis and H. viridissima; low budding rate combined with relatively low stress tolerance in H. oxycnida). Stress tolerance and asexual reproduction increased with food, but there were clear interspecific differences in this relationship. Across all strains, stress tolerance and budding rate were significantly negatively related on the low and medium, but not the high food level. These results suggest that resource allocation trade-offs are involved in determining life history traits in hydra; populations/species can be broadly positioned on a fast-slow life history continuum, and response to variation in food varies along this continuum.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Dietary restriction
Food variability
Hydra
Life history evolution
Resource allocation trade-offs
Megjelenés:Hydrobiologia. - 766 : 1 (2015), p. 121-133. -
További szerzők:Bradács Flóra Hóka Nikolett Kozma Noémi Miklós Máté (1994-) (biológus) Mucza Orsolya Lénárt Kinga (1994-) (biológus) Ősz Zsófia Sebestyén Flóra (1993-) (biológus) Barta Zoltán (1967-) (biológus, zoológus)
Pályázati támogatás:SROP-4.2.2.B-15/1/KONV-2015-0001
Egyéb
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
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