Effects of food availability on asexual reproduction and stress tolerance along the fast–slow life history continuum in freshwater hydra (Cnidaria: Hydrozoa)

Tökölyi, Jácint; Bradács, Flóra; Hóka, Nikolett; Kozma, Noémi; Miklós, Máté; Mucza, Orsolya; Lénárt, Kinga; Ősz, Zsófia; Sebestyén, Flóra; Barta, Zoltán

doi:10.1007/s10750-015-2449-0

Cited by 24 publications

(19 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Within rotifers, for instance, closely related species may show increased or decreased longevity when exposed to the same food restriction treatment (Kirk, 2001). In hydra there is no evidence so far for dietary restrictionmediated increases in self maintenance levels (Bridge et al, 2010;Tökölyi et al, 2016), although species differ in the way in which oxidative stress tolerance is maintained in the face of reduced food availability . Secondly, food shortage might signal increased future mortality risk, resulting in higher investment into reproduction and a reduction in survival, a strategy termed "terminal investment" (Clutton-Brock, 1984;Fischer et al, 2009;McNamara et al, 2009).…”

Section: Introductionmentioning

confidence: 99%

“…On the other hand, a reduction in the rate of reproduction and maintenance of somatic functions in the face of challenging conditions has been observed, e.g., in reef corals (Leuzinger et al, 2011), and is generally predicted to occur in long-lived, iteroparous animals that are expected to favor survival over current reproduction (e.g., Gaillard et al, 2000;Therrien et al, 2008;Kitaysky et al, 2010;Monteith et al, 2013). This is somewhat surprising since H. oligactis is a species with a relatively fast life history (it is characterized by a high rate of asexual reproduction and low tolerance against oxidative stress; Tökölyi et al, 2016).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Resource allocation and post-reproductive degeneration in the freshwater cnidarian Hydra oligactis (Pallas, 1766)

Tökölyi

Ősz

Sebestyén

et al. 2017

Zoology

Self Cite

View full text Add to dashboard Cite

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.

show abstract

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

Resource allocation and post-reproductive degeneration in the freshwater cnidarian Hydra oligactis (Pallas, 1766)

Tökölyi

Ősz

Sebestyén

et al. 2017

Zoology

Self Cite

View full text Add to dashboard Cite

show abstract

“…; Karntanut & Pascoe ; Tökölyi et al. ). This variation appears to be linked to reproductive strategies, because Hydra species with a higher rate of asexual reproduction showed lower resistance to experimentally induced oxidative stress (Tökölyi et al.…”

mentioning

confidence: 99%

“…This variation appears to be linked to reproductive strategies, because Hydra species with a higher rate of asexual reproduction showed lower resistance to experimentally induced oxidative stress (Tökölyi et al. ). However, little is known about variation within or between populations.…”

mentioning

confidence: 99%

Life history traits and previous exposure predict resistance to UV irradiation in the freshwater cnidarian Hydra oligactis

Tökölyi

Kozma

Sebestyén

et al. 2017

Invertebrate Biology

Self Cite

View full text Add to dashboard Cite

Abiotic stress is an important source of mortality for cnidarians and is likely to be a major factor shaping their life histories. In freshwater hydra, the ability to withstand exogenous sources of stress varies between species and populations, but little is known about the factors responsible for this variation. Here, we investigated resistance to UV irradiation in Hydra oligactis, a common temperate freshwater cnidarian. We collected polyps from 12 populations and propagated these asexually under standard conditions in the laboratory to obtain 69 laboratory clonal lines with a total of 324 polyps of different age. We measured the size of polyps and recorded their budding rate. In addition, a subset of animals was exposed to hormetic treatment, where experimental animals received a short, sublethal irradiation 2 d before testing their resistance to a higher dose. We investigated how life history traits (age, size, and budding rate), hormetic treatment, and the interaction between life history traits and hormetic treatment relate to the ability of hydra polyps to tolerate high doses of UV irradiation. In multivariate models controlling for the effect of other variables, stress tolerance was positively related to age (lower tolerance in freshly detached buds compared to adult hydra) and size (higher tolerance in polyps with a large body column). Budding rate was negatively associated with stress tolerance. Hormetic treatment increased resistance to UV irradiation, but we found no evidence for an interaction between hormetic response and any of the life history traits, suggesting that the ability to upregulate physiological defense mechanisms after exposure to mild stress does not depend on the life history background of the individuals.

show abstract

“…Correlation may be related either to phylogenetic constraints or to trade‐offs on resource allocation (Braendle, Heyland, & Flatt, ). In conditions of limited resources, the allocation of the resource to one function may restrict investment in another, resulting in trade‐offs among optimal traits for survival and reproduction (Braendle et al, ; Stearns, ; Tökölyi et al, ). For example, benthic species are larger than meroplanktonic species, which require more energy to release a medusa (Figure j).…”

Section: Discussionmentioning

confidence: 99%

Traits and depth: What do hydroids tell us about morphology and life‐history strategies in the deep sea?

Fernandez

Collins

Gittenberger

et al. 2020

Global Ecol Biogeogr

View full text Add to dashboard Cite

Aim Traits affect the survival and reproduction of individuals in different habitat conditions, ultimately altering their distributions. In the oceans, changes in environmental conditions with bathymetry may influence the occurrence of specific traits. Therefore, characterizing trait variation with depth can illuminate drivers related to the distribution of diversity of forms, functions, and life histories. We aimed to investigate patterns of variation in the diversified life histories and morphologies of hydroids with depth, integrating these patterns with the natural history of the group and ecological principles of the deep sea. Location Atlantic Ocean and adjacent polar seas, from 50 to 5,330 m deep. Time period Present day. Major taxa studied Hydrozoa. Methods Analyses were based on 14 traits collected for a total of 4,668 specimens of hydroids, belonging to 438 species. Records were divided into 12 depth strata for comparisons. We evaluated: how each trait varies with depth; whether variation in some traits is affected by the presence of other traits; how traits covary; and similarities in trait compositions among depth strata. Results Traits of hydroids vary with depth, with more pronounced differences for regions deeper than 1,000 m. Hydroids are generally smaller, infertile, solitary, meroplanktonic, and devoid of protective structures with increasing depth. The relationship, however, is not always linear. Also, some covariation and correlation between traits was evident. For example, depth may affect size differently according to the presence of specific traits such as structures protecting against predation. The lower proportion of fertile specimens recorded in the deep sea suggests that chances for genetic recombination are reduced in deep‐sea populations, ultimately leading to a slower rate of evolution. Main conclusions We identified novel trends in hydroid trait variation with depth by combining observations on morphology, ecology, and life history, clarifying selection pressures on hydroids in the deep sea.

show abstract

Effects of food availability on asexual reproduction and stress tolerance along the fast–slow life history continuum in freshwater hydra (Cnidaria: Hydrozoa)

Cited by 24 publications

References 46 publications

Resource allocation and post-reproductive degeneration in the freshwater cnidarian Hydra oligactis (Pallas, 1766)

Resource allocation and post-reproductive degeneration in the freshwater cnidarian Hydra oligactis (Pallas, 1766)

Life history traits and previous exposure predict resistance to UV irradiation in the freshwater cnidarian Hydra oligactis

Traits and depth: What do hydroids tell us about morphology and life‐history strategies in the deep sea?

Contact Info

Product

Resources

About