Declining fruit production before death in a widely distributed tree species, Sorbus aucuparia L.
Trees are commonly thought to increase their seed production before death. We tested this terminal investment hypothesis using long-term data on rowan trees ( Sorbus aucuparia ) and found no support. Rather, seed production declined significantly before death, which points to the potential detrimental effects of reproductive senescence on regeneration in stands of old trees.
Aging poses a fundamental challenge for long-lived organisms. As mortality changes with with age due to actuarial senescence, reproductive senescence may also lead to declines in fertility. However, life history theory predicts that reproductive investment should increase before mortality to maximize lifetime reproductive success, a phenomenon termed terminal investment.
To date, it is unclear whether long-lived, indeterminantly growing trees experience reproductive senescence or display terminal investment.
We investigated fruit production of rowan (Sorbus aucuparia L.), widely distributed trees that live up to 150 years, as they approached death.
In our study population in Poland’s Carpathian Mountains, 79 trees that died produced up to 20% fewer fruits in the years before their demise compared to 199 surviving trees of the same population.
The pattern of reproductive investment in S. aucuparia is suggestive of age-independent reproductive senescence rather than terminal investment. These findings highlight that the understanding of the generality of life history strategies across diverse taxa of perennial plants is still in its infancy.
KeywordsReproductive trade-offs Fruit production Senescence Sorbus aucuparia Terminal investment Rosaceae
This work was supported by the US National Science Foundation (grant number DEB-1256394 to W.D.K.), Polish National Science Foundation (Sonatina grant number 2017/24/C/NZ8/00151 to M.B.), the Polish State Committee for Scientific Research (grant numbers 6 P04G 045 21, 3 P04G 111 25 to M.Z.), the Polish Ministry of Science and Higher Education (grant number N304 362938 to M.Z.), and the statutory fund of the Institute of Botany of the Polish Academy of Sciences.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Brooks ME, Kristensen K, van Benthem KJ, Magnusson A, Berg CW, Nielsen A, Skaug HJ, Maechler M, Bolker BM (2017) Modeling zero-inflated count data with glmmTMB. bioRxiv preprint bioRxiv:132753. https://doi.org/10.1101/132753
- Hartig F (2018) DHARMa: residual diagnostics for hierarchical (multi-level/mixed) regression models. R package version 0.1.6Google Scholar
- Magnusson A, Skaug HJ, Nielsen A, Berg CW, Kristensen K, Maechler M, van Bentham KJ, Bolker BM, Brooks ME (2017) glmmTMB: Generalized linear mixed models using template model builder. R package version 01.3Google Scholar
- Medawar PB (1952) An unsolved problem of biology. H.K. Lewis & Co, LondonGoogle Scholar
- Pesendorfer MB, Bogdziewicz M, Koenig WD, Ledwoń M, Żywiec M (2018) Data for “Declining fruit production before death in a widely distributed tree, Sorbus aucuparia L.”. V1. FigShare. [Dataset]. https://doi.org/10.6084/m9.figshare.7330052.v1
- R Core Team (2018) R: a language and environment for statistical computing. R software version 3.4.4Google Scholar
- Salguero-Gómez R, Jones OR, Archer CA, Buckley YM, Che-Castaldo J, Caswell C, Hodgson D, Scheuerlein A, Conde DA, Brinks E, Buhr H (2015) The COMPADRE Plant Matrix Database: an online repository for plant population dynamics. J Ecol 103:202–218. https://doi.org/10.1111/1365-2745.12334 CrossRefGoogle Scholar
- Salguero-Gómez R, Jones OR, Jongejans E, Blomberg SP, Hodgson DJ, Mbeau-Ache C, Zuidema PA, de Kroon H, Buckley YM (2016) Fast–slow continuum and reproductive strategies structure plant life-history variation worldwide. Proc Natl Acad Sci 113:230–235. https://doi.org/10.1073/pnas.1506215112 CrossRefPubMedGoogle Scholar
- Sperens U (1997) Long-term variation in, and effects of fertiliser addition on, flower, fruit and seed production in the tree Sorbus aucuparia (Rosaceae). Ecography 20:521–534. https://doi.org/10.1111/j.1600-0587.1997.tb00421.x CrossRefGoogle Scholar
- Vacchiano G, Ascoli D, Berzaghi F, Lucas-Borja ME, Caignard T, Collalti A, Mairota P, Palaghianu C, Reyer CP, Sanders TG, Schermer E (2018) Reproducing reproduction: how to simulate mast seeding in forest models. Ecol Model 376:40–53. https://doi.org/10.1016/j.ecolmodel.2018.03.004 CrossRefGoogle Scholar
- Weismann A (1893) The germ-plasm: a theory of heredity. Scribner, New YorkGoogle Scholar
- Williams GC (1957) Pleiotropy, natural selection, and the evolution of senescence. Evolution 11:398–411. https://doi.org/10.1111/j.1558-5646.1957.tb02911.x CrossRefGoogle Scholar
- Wohlleben P (2016) The hidden life of trees. Greystone, VancouverGoogle Scholar