ArticleProceedings of the National Academy of Sciences of the United States of America2015
Constant mortality and fertility over age in Hydra.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 46 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
46 citing papers in PubMed.
- Environmental variability versus extrinsic mortality as correlates of mammalian lifespan: a pre-specified comparative analysis with phylogenetic and deep-time evidence.Biogerontology · 2026Article
- Early-life stress reduces senescence in the field for an indeterminately growing ectotherm.Evolution letters · 2026Article
- Conditional Senescence and Longevity Mechanisms in Early-Branching Metazoans: Insights fromCurrent issues in molecular biology · 2026Article
- Telomerase expression and activity in the immortal cnidarian Hydra.Frontiers in cell and developmental biology · 2026Article
- The evolution of cancer and ageing: a history of constraint.Nature reviews. Cancer · 2025Review
- IsJournal of developmental biology · 2025Review
- The dynamic genomes of Hydra and the anciently active repeat complement of animal chromosomes.Genome biology · 2025Article
- Exploring the Relationship of Transposable Elements and Ageing: Causes and Consequences.Genome biology and evolution · 2025Review
- Regeneration and Musculature in HalvedIntegrative organismal biology (Oxford, England) · 2025Article
- Article
- Agelessness is possible under the disposable soma theory but system complexity makes it unlikely.Journal of theoretical biology · 2024Article
- Heat shock response during the resolution of inflammation and its progressive suppression in chronic-degenerative inflammatory diseases.Cell stress & chaperones · 2024Review
- The Hunger Games as the Key to Happily Ever After?The journals of gerontology. Series A, Biological sciences and medical sciences · 2023Review
- Biological Restraints on Indefinite Survival.Cold Spring Harbor perspectives in medicine · 2023Review
- Metabolism, homeostasis, and aging.Trends in endocrinology and metabolism: TEM · 2023Review
- A chromosome-scale epigenetic map of theGenome research · 2023Article
- Dynamic regulation of gonadal transposon control across the lifespan of the naturally short-lived African turquoise killifish.Genome research · 2023Article
- Semelparous Death as one Element of Iteroparous Aging Gone Large.Frontiers in genetics · 2022Article
- Cellular, Metabolic, and Developmental Dimensions of Whole-Body Regeneration inCold Spring Harbor perspectives in biology · 2021Review
- Predation has small, short-term, and in certain conditions random effects on the evolution of aging.BMC ecology and evolution · 2021Article
Corrections and comments
- Commented on by
Authors and funding
6 authors.
Funding
Abstract
Senescence, the increase in mortality and decline in fertility with age after maturity, was thought to be inevitable for all multicellular species capable of repeated breeding. Recent theoretical advances and compilations of data suggest that mortality and fertility trajectories can go up or down, or remain constant with age, but the data are scanty and problematic. Here, we present compelling evidence for constant age-specific death and reproduction rates in Hydra, a basal metazoan, in a set of experiments comprising more than 3.9 million days of observations of individual Hydra. Our data show that 2,256 Hydra from two closely related species in two laboratories in 12 cohorts, with cohort age ranging from 0 to more than 41 y, have extremely low, constant rates of mortality. Fertility rates for Hydra did not systematically decline with advancing age. This falsifies the universality of the theories of the evolution of aging that posit that all species deteriorate with age after maturity. The nonsenescent life history of Hydra implies levels of maintenance and repair that are sufficient to prevent the accumulation of damage for at least decades after maturity, far longer than the short life expectancy of Hydra in the wild. A high proportion of stem cells, constant and rapid cell turnover, few cell types, a simple body plan, and the fact that the germ line is not segregated from the soma are characteristics of Hydra that may make nonsenescence feasible. Nonsenescence may be optimal because lifetime reproduction may be enhanced more by extending adult life spans than by increasing daily fertility.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.