Phenological shifts

Phenological sensitivity to environmental cues

Decades of research indicates that spring phenological events like budburst and leafout respond to three main environmental cues: Forcing (warm temperatures in the spring) Chilling (cool temperatures in dormant season) and Photoperiod.

However there is muich debate about which cue exerts the strongest control on spring phenology, and it is clear that species, populations and even individuals differ in the strength of their responses to these three cues.

Several our of synthesis paper based on a database of almost a century's worth of experiments in controlled environments indicate that cues responses are strongly phylogenetically conserved and appear to co-evolve with other suits of functional traits along the acquisitive/competitive spectrum.

Here are some of our relevant publications:

Morales‐Castilla, I., Davies, T.J., Legault, G. Buonaiuto, D.M., Chamberlain, C.J., Ettinger, A., Garner, M., Jones, F., Loughnan, D., Pearse, W., Sodhi, D. & Wolkovich, E.M. (2024). Phylogenetic estimates of species-level phenology improve ecological forecasting. Nature Climate Change. https://doi.org/10.1038/s41558-024-02102-2 (pdf)

Buonaiuto, D.M., Donohue, M. and Wolkovich, E.M. (2023). Experimental designs for testing the interactive effects of temperature and light in ecology: the problem of periodicity. Functional Ecology. 37, 1747– 1756. https://doi.org/10.1111/1365-2435.14329 (pdf)

Ettinger, A.K., Buonaiuto, D.M., Chamberlain, C.J., Morales‐Castilla, I. and Wolkovich, E.M. (2021), Spatial and temporal shifts in photoperiod with climate change. New Phytologist, 230: 462-474. https://doi.org/10.1111/nph.17172 (pdf)

Ecology and evolution of flower-leaf sequences

Why do some tree species produce their flowers before their leaves each spring while others leafout first?

This flowering-first phenological sequence, known as hysteranthy, is not only a desirable horticultural trait, but appears to have evolved to in both wind and insect pollinated taxa to facilitate effective pollination and and some cases reduce water stress.

Here are some of our relevant publications:

Buonaiuto, D.M., Davies, T.J., Collins, S.C. and Wolkovich, E.M. (2024), Ecological drivers of flower–leaf sequences: aridity and proxies for pollinator attraction select for flowering-first in the American plums. New Phytologist. https://doi.org/10.1111/nph.19685 (pdf)

Buonaiuto, D.M., and Wolkovich, E.M. (2021). Differences between flower and leaf phenological responses to environmental variation drive shifts in spring phenological sequences of temperate woody plants. Journal of Ecology, 109, 2922– 2933. https://doi.org/10.1111/1365-2745.13708 (pdf)

Buonaiuto, D.M., Morales‐Castilla, I. and Wolkovich, E.M. (2021). Reconciling competing hypotheses regarding flower–leaf sequences in temperate forests for fundamental and global change biology. New Phytologist, 229: 1206-1214. https://doi.org/10.1111/nph.16848 (pdf)

Seasonal priority effects and plant competition

Plant species that become active early in the season can gain a competitive advantage by accessing limited resources ahead of their dormant competitors. Growing research suggests these ``seasonal priority effects" contribute to the dominance of weedy and invasive species. More generally, these effects may be a critical mechanism for coexistence, providing weaker competitors with a ``head start'' in the race for resource gain.

Climate change will alter the strength of seasonal priority effects, which will have

down-stream consequences for the structure of plant communities. To improve our ability to predict how phenological shifts will impact plant interactions, we focus on quantifying both the differences in species' responses to altered environments and how these changes impact competition and, therefore, community assemblly.

Here are some of our relevant publications:

Buonaiuto, D.M., and Wolkovich E.M. (2023). Contrasting responses to climate variability generate seasonal priority effects between native and invasive forest herbs. Journal of Ecology. 111, 1711– 1721. https://doi.org/10.1111/1365-2745.14138 (pdf)

Sexual dimorphism in flowering phenology

Dichogamy—the phenological seperation of male and female flowering—is a widespread adaptation in plants that increases their reproductive success and enhances their fitness.

Phenological differences between male and female flowers can be highly sensitive to environmental variation—and with widespread evidence of shifts flower phenology, climate change may alter the sequences of male and female flowering for a diversity of taxa around the globe.

To date, studies of plasticity in dichogamy due to environmental variation have been restricted to a limited number of species, and therefore we currently lack a broad understanding of both the extent to which climate change may alter patterns of dichogamy and the potential implications of these shifts for plant reproduction.

Here are some of our relevant publications:

Wu, Zhaofei; Gong, Yufeng; Zohner, Constantin; Vitasse, Yann; Li, Mingwei; Nie, Yangjing; Buonaiuto, D.M.; Cerdeira Morellato, Leonor Patricia; Guo, Zhendong; Wang, Shuxin; Wang, Nan; Wang, Hongzhou; Fu, Yongshuo. Stabilizing mechanisms enable dioecious trees to maintain synchrony in spring budburst under climate warming. New Phytologist. https://doi.org/10.1111/nph.70290 (pdf)

Buonaiuto, D. M. (2024), How Climate Change May Impact Plant Reproduction and Fitness by Altering the Temporal Separation of Male and Female Flowering. Global Change Biology, 30: e17533. https://doi.org/10.1111/gcb.17533 (pdf)