Amy Whipple

Northern Arizona University | NAU · Center for Adaptive Western Landscapes

Multispecies interbreeding networks, or syngameons, have been increasingly reported in natural systems. However, the formation, structure, and maintenance of syngameons have received little attention. Through gene flow, syngameons can increase genetic diversity, facilitate the colonization of new environments, and contribute to hybrid speciation. I...

Lack of tree fecundity data across climatic gradients precludes the analysis of how seed supply contributes to global variation in forest regeneration and biotic interactions responsible for biodiversity. A global synthesis of raw seedproduction data shows a 250‐fold increase in seed abundance from cold‐dry to warm‐wet climates, driven primarily by...

The relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundat...

Significance Suitable habitats for forest trees may be shifting fast with recent climate change. Studies tracking the shift in suitable habitat for forests have been inconclusive, in part because responses in tree fecundity and seedling establishment can diverge. Analysis of both components at a continental scale reveals a poleward migration of nor...

Variation in gene expression among natural populations are key contributors to adaptive evolution. Understanding the architecture underlying adaptive trait evolution provides insights into the adaptive potential of populations exposed to novel selective pressures. We investigated patterns and processes driving trait differentiation under novel clim...

Despite its importance for forest regeneration, food webs, and human economies, changes in tree fecundity with tree size and age remain largely unknown. The allometric increase with tree diameter assumed in ecological models would substantially overestimate seed contributions from large trees if fecundity eventually declines with size. Current esti...

Seedling emergence, survival, morphological and physiological traits, and oxidative stress resistance of southwestern white pine (Pinus strobiformis Engelm.) were studied in response to warming treatments applied during embryogenesis, germination, and early seedling growth. Daytime air temperature surrounding cones in tree canopies was warmed by +2...

A Correction to this paper has been published: https://doi.org/10.1038/s41467-021-22025-2

Indirect climate effects on tree fecundity that come through variation in size and growth (climate-condition interactions) are not currently part of models used to predict future forests. Trends in species abundances predicted from meta-analyses and species distribution models will be misleading if they depend on the conditions of individuals. Here...

Extant conifer species may be susceptible to rapid environmental change owing to their long generation times, but could also be resilient due to high levels of standing genetic diversity. Hybridisation between closely related species can increase genetic diversity and generate novel allelic combinations capable of fuelling adaptive evolution. Our s...

Background Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and...

Background Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and...

Background Forest dieback driven by rapid climate warming threatens ecosystems worldwide. The health of forested ecosystems depends on how tree species respond to warming during all life history stages. While it is known that seed development is temperature-sensitive, little is known about possible effects of climate warming on seed development and...

Pinus strobiformis (P. strobiformis) faces dual threats of climate change shifting its environmental niche and mortality due to a non-native, invasive fungal pathogen. To inform efforts to sustain this species, we established three field experimental common garden trials along an elevational gradient with drought treatments to assess trait response...

In forestry, common garden experiments traditionally require manual measurements and visual inspections. Unmanned aircraft systems (UAS) are a newer method of monitoring plants that are potentially more efficient than traditional techniques. This study had two objectives: to assess the size and mortality of Pinus strobiformis seedlings using UAS, a...

We implemented multilocus selection in a spatially‐explicit, individual‐based framework that enables multivariate environmental gradients to drive selection in many loci as a new module for the landscape genetics programs, CDPOP and CDMetaPOP. Our module simulates multilocus selection using a linear additive model, providing a flexible platform to...

Citizen science use in common garden experiments

Southwestern white pine (Pinus strobiformis; SWWP) is a native tree species threatened by the rapidly changing climate and a non-native tree disease (white pine blister rust). Our team of researchers studies the ecology and evolution of SWWP across its range in the United States and Mexico to find solutions for sustaining this tree. Genetic and env...

Ecophysiological measures of plant water use were measured across Pinus strobiformis seedlings replicated across two warming treatments: 1) warmed versus control cone warming treatments during the final summer of seed development, and 2) three temperatures imposed during the first four months of seedling growth.

Chlorophyll a fluorescence of PSII and foliar temperature investigated following controlled environmental warming during: (1) seed development, and (2) first four months of seedling growth.

Ecophysiological responses of southwestern white pine (P. strobiformis) to controlled temperature manipulations during both seed development and the first four months of seedling growth. Bulk modulus of elasticity and turgor loss point were differentially responsive to temperature treatments depending on the timing of temperature manipulation. We c...

Ecophysiological responses of southwestern white pine (P. strobiformis) to controlled temperature manipulations during both seed development and the first four months of seedling growth. Bulk modulus of elasticity and turgor loss point were differentially responsive to temperature treatments depending on the timing of temperature manipulation. We c...

Worldwide, trees are confronting increased temperature and aridity, exacerbating susceptibility to herbivory. Long-term studies comparing patterns of plant performance through drought can help identify variation among and within populations in vulnerability to climate change and herbivory. We use long-term monitoring data to examine our overarching...

Advances in chromatin state mapping, high-throughput DNA sequencing, and bioinformatics have revolutionized the study and interpretability of epigenomic variation. The increasing feasibility of obtaining and analyzing detailed information on epigenetic mechanisms across many individuals and populations has enabled the study of epigenomic variation...

The interactions among climate change, plant genetic variation and fungal mutualists are poorly understood, but probably important to plant survival under drought. We examined these interactions by studying the ectomycorrhizal fungal (EMF) communities of pinyon pine seedlings (Pinus edulis) planted in a wildland ecosystem experiencing two decades o...

El pino blanco del sudoeste (Pinus strobiformis, SWWP) es una especie arbórea nativa, amenazada por el cambio climático y una enfermedad introducida (roya de ampollas de pino blanco). Nuestro equipo de investigadores estudia la ecología y la evolución de SWWP en toda su distribución en los Estados Unidos y México para encontrar soluciones para la s...

High temperatures associated with climate change are expected to be detrimental for aspects of plant reproduction, such as pollen viability. We hypothesized that (1) higher peak temperatures predicted with climate change would have a minimal effect on pollen viability, while high temperatures during pollen germination would negatively affect pollen...

This poster describes results of a brief greenhouse experiment designed to understand how the physiology and morphology of 6-month old southwestern white pine (P. strobiformis) seedlings is influenced by controlled drought and warming.

Interactions between extrinsic factors, such as disruptive selection, and intrinsic factors, such as genetic incompatibilities among loci, often contribute towards the maintenance of species boundaries. The relative roles of these factors in the establishment of reproductive isolation can be examined using species pairs characterized by gene flow t...

Significance Soil microbes influence plant performance and may be critical to the persistence of some plants with climate change. However, microbes are highly diverse, and individuals of the same plant species often associate with different microbes. We examined the importance of soil microbes to the growth and survival of a widespread pine under d...

Interactions between extrinsic factors, such as disruptive selection, and intrinsic factors, such as genetic incompatibilities among loci, can contribute to the maintenance of species boundaries. The relative roles of these factors in the establishment of reproductive isolation can be examined using species pairs characterized by gene flow througho...

A collaborative team of researchers from the US and Mexico have begun an exciting new research project funded by The National Science Foundation’s Macrosystems Biology program. We will study ecological and evolutionary processes affecting the distribution of southwestern white pine (Pinus strobiformis; SWWP), an important tree species of mixed coni...

The study of epigenomic variation at the landscape-level in plants may add important insight to studies of adaptive variation. A major goal of landscape genomic studies is to identify genomic regions contributing to adaptive variation across the landscape. Heritable variation in epigenetic marks, resulting in transgenerational plasticity, can influ...

Forest and woodland ecosystems may be strongly affected by climate change influences on tree population processes such as seed production and seedling recruitment. Yet climate effects on seed production are generally poorly understood, particularly for trees that exhibit masting behavior (i.e. high synchronicity and high inter-annual variability in...

Although the importance of plant-associated microbes is increasingly recognized, little is known about the biotic and abiotic factors that determine the composition of that microbiome. We examined the influence of plant genetic variation, and two stressors, one biotic and one abiotic, on the ectomycorrhizal (EM) fungal community of a dominant tree...

Elucidating phylogenetic relationships and species boundaries within complex taxonomic groups is challenging for intrinsic and extrinsic (i.e., technical) reasons. Mexican pinyon pines are a complex group whose phylogenetic relationships and species boundaries have been widely studied but poorly resolved, partly due to intrinsic ecological and evol...

SPIDER MONKEYS (GENUS: Ateles) are a widespread Neotropical primate with a highly plastic socioecological strategy. However, the Central American species, Ateles geoffroyi, was recently re-listed as endangered due to the accelerated loss of forest across the subcontinent. There is inconsistent evidence that spider monkey populations could persist w...

Unlabelled: • Premise of the study: Even though dioecy is a dominant sexual system among gymnosperms, little is known about its evolutionary history. Pinus johannis may represent a model system because unisexual and monoecious individuals compose its populations. The presence of unisexual individuals in other Pinus species is a consequence of se...

Background/Question/Methods Recent, record droughts in the American Southwest have resulted in high mortality of long-lived pinyon pine (Pinus edulis) that represents a foundation species of the 3rd largest vegetation type in the U.S. We examined the hypothesis that this mortality is both a major ecological event as well as an evolutionary event...

Background/Question/Methods Recent research demonstrates that aboveground and belowground communities have reciprocal influences on one another that can alter ecosystem function. However, the extent to which these interactions are influenced by global change factors such as altered climate regimes and invasive species remains poorly understood. W...

Both plant genotype and yearly abiotic variation affect herbivore population sizes, but long-term data have rarely been used to contrast the relative contributions of each. Using a hierarchical Bayesian model, we directly compare effects of these two factors on the population size of a common herbivore, Aceria parapopuli, on Populus angustifolia ×...

Background/Question/Methods Weather data is necessary for answering many ecological questions, but is often unavailable for locations of interest. Modeled climate data is a potential solution to this problem. Parameter-elevation Regressions on Independent Slopes Model (PRISM) and ClimateWNA are two popular sources for modeled climate data. PRISM...

Mononucleotide microsatellites markers are useful for detecting genetic variation among individuals; however, scoring can be error-prone. We developed a new approach to improve the accuracy of allele scoring. A set of 14 mononucleotide microsatellite primers of the chloroplast were developed based on published Pinus spp. chloroplast genomes. Due to...

PREMISE OF STUDY: Bisexuality (male and female function in one structure) has been reported as a key innovation of angiosperms. Although there are several reports of "teratological" bisporangiate (bisexual) cones in gymnosperms, there have been none on the viability of their ovules and pollen. Analyses of the development and arrangement of female a...

Background/Question/Methods Pinus edulis (pinyon pine) is a foundation tree species in the southwestern United States that has experienced high levels of mortality in a drought extending from the mid-1990s to the present. Despite high mortality levels, radial growth of pinyon pine in northern Arizona over the past century shows an increasing trend...

Background/Question/Methods Current climate models predict a shift to warmer, drier conditions in the southwestern US.While major shifts in plant distribution are expected to follow these climate changes, interactions among species and intraspecific genetic variation could alter these projections. In this presentation, we examine the drought-relate...

_Pinus edulis_ (piñon pine) is found across 35% of the Colorado Plateau and is a foundation species in the piñon-juniper woodlands of the Southwest. Piñon pine mortality in the recent drought has been high and climate change models forecast a warmer future for the region, which will increase piñon pine water stress. In order to predict the fate of...

Host-race formation is promoted by genetic trade-offs in the ability of herbivores to use alternate hosts, including trade-offs due to differential timing of host-plant availability. We examined the role of phenology in limiting host-plant use in the goldenrod gall fly (Eurosta solidaginis) by determining: (1) whether phenology limits alternate hos...

A 37-minute video that offers insights to several interactions of the host-plant goldenrod with its herbivorous gall-inducing fly, and the natural enemies (parasitoid wasps, predaceous inquiline beetle, and birds) of the gall fly. The video is available via streaming at http://www.facstaff.bucknell.edu/abrahmsn/solidago/gallfly_video.html or from a...

Stonefly nymphs (Acroneuria carolinensis) were used as a bioindicator of the toxicity of coal mine drainage, and of the interaction between low pH and dissolved metals at severe pollutant levels. Laboratory experiments were done to determine the mean life expectancy of stoneflies subjected to simulated mine drainage with various levels of metals an...