Beyond climate? Factors determining fruiting and flowering phenology across a genus over 117 years

Variance partitioning of flowering phenology for all species in the genus Leavenworthia

Kelsey is very happy to have published her article on flowering and fruiting phenology across the entire genus of Leavenworthia, a taxon with some very highly-endemic species! Moreover, her research has been highlighted by the American Journal of Botany, and featured in a mini-documentary and a press release by Washington University in Saint Louis!

To date, nearly all work on phenology has assumed that climate is the driving factor behind changes in phenology that have been observed across the past century and more.

However, the effect of other factors like geography (aside from climate), mating system, range overlap with congenerics, and species identity have been largely overlooked.

Kelsey found that both flowering and fruiting dates in Leavenworthia have advanced by ~2 days per decade over the last 117 years. Climate did indeed account for the majority of explained variance in phenology, with non-climatic factors capturing <11% of explained variance.

This is but one of few (any?) published analyses taking a whole-taxon look at phenology.

Understanding how climatic and non-climatic factors shape phenology is important to assessing species’ vulnerabilities to climate change. This work suggests that in general, we do not need to know more than “just climate” to predict species’ responses to climate change. However, it also highlights that we may not always know the exact climatic factors driving shifts in phenology. It also underscores the importance of herbarium specimens for assessing “baseline” trends in biodiversity in relation to changing environments.

Bartlett*, K., Austin, M.A., Beck, J., Zanne**, A., and Smith**, A.B. 2023. Beyond climate? Factors determining fruiting and flowering phenology across a genus over 117 years. American Journal of Botany 110:e16188. * undergraduate author * co-senior authors. [open access]