Biology subjects

Primack, R. B.

Publications and source records attributed to Primack, R. B..

4 recordsLinked to original sources

bioRxiv2023

Phenological mismatch between trees and wildflowers: Reconciling divergent findings in two recent analyses

O_LIRecent evidence suggests that community science and herbarium datasets yield similar estimates of species phenological sensitivities to temperature. Despite this, two recent studies by Alecrim et al. (2023) and Miller et al. (2022) found contradictory results when investigating an identical ecological mechanism (phenological mismatch of wildflower flowering and of shading by deciduous trees; "phenological escape") with separate datasets. C_LIO_LIHere, we investigated whether differences between the two studies results could be reconciled by testing four hypotheses related to model design, species selection, spatiotemporal data extent, and phenophase selection. C_LIO_LIHybrid model structures brought results from the two datasets closer together but did not fully reconcile the differences between the studies. Cropping the datasets to match spatial and temporal extents appeared to reconcile most differences but only at the cost of much higher uncertainty associated with reduced sample size. Neither species selection nor phenophase selection seemed to be responsible for differences in results. C_LIO_LISynthesis: Our analysis suggests that although species-level estimates of phenological sensitivity may be similar between crowd-sourced and herbarium datasets, inherent differences in the types and extent of data may lead to contradictory inference about complex biotic interactions. We conclude that, until community science data repositories grow to match the range of climate conditions present in herbarium collections or until herbarium collections grow to match the spatial extent and temporal frequency of community science repositories, ecological studies should ideally be evaluated using both datasets to test the possibility of biased results from either. C_LI

ecology↗

bioRxiv2022

Wildflower phenological escape differs by continent and spring temperature

Temperate understory plant species are at risk from climate change and anthropogenic threats that include increased deer herbivory, habitat loss, pollinator declines and mismatch, and nutrient pollution. Recent work suggests that spring ephemeral wildflowers may be at additional risk due to phenological mismatch with deciduous canopy trees. The study of this dynamic, commonly referred to as "phenological escape", and its sensitivity to spring temperature is limited to eastern North America. Here, we use herbarium specimens to show that phenological sensitivity to spring temperature is remarkably conserved for understory wildflowers across North America, Europe, and Asia, but that canopy trees in North America are significantly more sensitive to spring temperature compared to in Asia and Europe. We predict that advancing tree phenology will lead to decreasing spring light windows in North America while spring light windows will be maintained or even increase in Asia and Europe in response to projected climate warming.

ecology↗

bioRxiv2022

Consistent, linear phenological shifts across a century of observations in South Korea

The Korea Meteorological Agency (KMA) has monitored flowering dates over the past 100 years for seven economically important woody plant species. This unique dataset is perfect for understanding whether historical patterns of phenological plasticity are breaking down in the face of recent and rapid climate change. Here we show that a scientist armed only 50 years into this study would have been able to predict the phenological shifts of the last 50 years with a high degree of accuracy. This is despite record-breaking warm temperatures and unprecedented early flowering, suggesting consistency in phenological shifts over time.

ecology↗

bioRxiv2021

Disorder or a new order: how climate change affects phenological variability

Advancing spring phenology is a well-documented consequence of anthropogenic climate change, but it is not well understood how climate change will affect the variability of phenology year-to-year. Species phenological timings reflect adaptation to a broad suite of abiotic needs (e.g. thermal energy) and biotic interactions (e.g. predation and pollination), and changes in patterns of variability may disrupt those adaptations and interactions. Here, we present a geographically and taxonomically broad analysis of phenological shifts, temperature sensitivity, and changes in inter-annual variance encompassing nearly 10,000 long-term phenology time-series representing over 1,000 species across much of the northern hemisphere. We show that early-season species in colder and less seasonal regions were the most sensitive to temperature change and had the least variable phenologies. The timings of leaf-out, flowering, insect first-occurrence, and bird arrival have all shifted earlier and tend to be less variable in warmer years. This has led leaf-out and flower phenology to become moderately but significantly less variable over time. These simultaneous changes in phenological averages and the variation around them have the potential to influence mismatches among interacting species that are difficult to anticipate if shifts in average are studied in isolation.

ecology↗