Biology subjects

Holeski, L. M.

Publications and source records attributed to Holeski, L. M..

4 recordsLinked to original sources

bioRxiv2026

Foliar striping and floral traits are correlated with higher reproductive output in crimson monkeyflowers

In plants, ecological interactions such as pollination depend on whole-plant phenotypes, where coordinated variation among vegetative, floral, and reproductive traits can shape reproductive success. However, empirical studies linking integrated phenotypes that include non-floral traits to reproductive outcomes within populations remain limited. While prior work has shown that crimson monkeyflowers exhibit heritable variation in foliar anthocyanin striping, the functional significance of the trait has been thus far unknown. Using plants derived from natural populations, we conducted field and greenhouse experiments to assess whether foliar striping is genetically correlated with traits related to pollinator attraction. We found that foliar striped plants consistently exhibit larger flowers, greater nectar rewards, and decreased proportions of viable pollen relative to non-striped plants. When we manipulated flowers within plants with and without foliar striping to allow only outcrossing or only self-fertilization in a field environment, we found that outcrossed flowers had higher reproductive success than did self-fertilized, with outcrossed flowers from plants with foliar striping producing the highest overall seed numbers and seed mass. Our results reveal patterns of coordinated foliar and floral trait variation and associated reproductive output that are consistent with a pollination syndrome framework. The link between foliar pigmentation and increased per-calyx reproductive output represents a novel association between foliar pigmentation and a broader evolutionary and ecological function.

ecology↗

bioRxiv2026

Climate Gradients and Habitat Discontinuity Structure Genetic Variation in a Spring-Specialist Plant

Background and AimsGroundwater-dependent ecosystems support disproportionate biodiversity in arid regions, yet the population genetics of spring-specialist plants remains poorly understood. Here, we present the first species-wide genetic dataset for crimson monkeyflower ( Mimulus verbenaceus, Phrymaceae), a spring-specialist plant distributed in seeps, springs, and associated riparian areas across desert regions of North America. MethodsUsing genome-wide reduced representation sequencing data consisting of 10,760 SNPs from 175 individuals across 17 populations, we characterized the patterns of genetic diversity using FST and Neis D. Population structure was assessed using ADMIXTURE and PCA. We examined the contributions of climate to range-wide genetic variation in crimson monkeyflower using redundancy analysis. Key ResultsPatterns of genetic differentiation were more consistent with those of spring-specialist animal taxa than those of upland plants or generalist riparian plants. We found strong population structure at both broad regional scales and at fine local scales. While riparian connectivity influenced local patterns of diversity, adaptation to local climatic variation was more influential at regional scales, with temperature, relative humidity, and a monsoon-driven climate gradient structuring genetic differentiation. ConclusionsOur findings highlight the distinctive influence of isolated perennial groundwater sources, as well as adaptation to climate, in shaping genetic variation in this spring-specialist plant. These findings suggest that spring-specialist plants deserve special consideration in ecological theory, management, and conservation.

evolutionary biology↗

bioRxiv2019

A test of the evolution of increased competitive ability in two invaded regions

O_LIFinding patterns that predict and explain the success of non-native species has been an important focus in invasion ecology. The evolution of increased competitive ability (EICA) hypothesis has been a frequently used framework to understand invasion success. Evolution of increased competitive ability predicts that 1. Non-native populations will escape from coevolved specialist herbivores and this release from specialist herbivores should result in relaxed selection pressure on specialist-related defense traits, 2. There will be a trade-off between allocation of resources for resistance against specialist herbivores and allocation to traits related to competitive ability and 3. This shift will allow more allocation to competitive ability traits.\nC_LIO_LIWe tested the predictions of EICA in the model plant Mimulus guttatus, a native of western North America (WNA). We compared how well the predictions of EICA fit patterns in two non-native regions, the United Kingdom (UK) and eastern North America (ENA). Coupled with extensive herbivore surveys we quantified genetic variation for herbivore resistance traits and fitness/ competitive ability traits to test adherence to the predictions of EICA in a common greenhouse environment.\nC_LIO_LIHerbivore communities differed significantly between WNA, UK, and ENA populations with evidence of specialist herbivore escape in the UK, but not necessarily the ENA plants. Compared to native plants, resistance traits were lower in non-native UK plants with the exception of trichome density, while the non-native ENA plants had equivalent or higher levels of herbivore resistance traits. The UK plants had increased competitive traits than native plants while the ENA plants had equivalent competitive traits to native plants. The UK plants, but not the ENA plants, showed some signs of tradeoffs between resistance traits and fitness/ competitive ability.\nC_LIO_LISynthesis. Plants from the UK conformed to predictions of EICA more closely than those from ENA. The UK invasion is an older, more successful invasion, suggesting that support for EICA may be highest in more successful invasions. The lack of comprehensive conformity of either non-native region to the predictions of EICA also leaves room for other hypotheses that may add to our mechanistic understanding of the success of non-native plant invasions.\nC_LI

ecology↗

bioRxiv2018

Mechanisms of a locally adaptive shift in allocation among growth, reproduction, and herbivore resistance in Mimulus guttatus

Environmental gradients can drive adaptive evolutionary shifts in plant resource allocation among growth, reproduction, and herbivore resistance. However, few studies have attempted to connect these adaptations to underlying physiological and genetic mechanisms. Here, we evaluate potential mechanisms responsible for a coordinated locally adaptive shift between growth, reproduction, and herbivore defense in the yellow monkeyflower, Mimulus guttatus. Through manipulative laboratory experiments we found that gibberellin (GA) growth hormones may play a role in the developmental divergence between perennial and annual ecotypes of M. guttatus. Further, we detected an interaction between a locally adaptive chromosomal inversion, DIV1, and GA addition. This finding is consistent with the inversion contributing to the evolutionary divergence between inland annual and coastal perennial ecotypes by reducing GA biosynthesis/activity in perennials. Finally, we found evidence that the DIV1 inversion is partially responsible for a coordinated shift in the divergence of growth, reproduction, and herbivore resistance traits between coastal perennial and inland annual M. guttatus. The inversion has already been established to have a substantial impact on the life-history shift between long-term growth and rapid reproduction. Here, we demonstrate that the DIV1 inversion also has sizable impacts on both the total abundance and composition of phytochemical compounds involved in herbivore resistance.

evolutionary biology↗