Biology subjects

Cornwell, W. K.

Publications and source records attributed to Cornwell, W. K..

5 recordsLinked to original sources

bioRxiv2026

Contrasting climate signals between native and introduced annual and perennial floras

Annual versus perennial life histories represent a fundamental axis of plant strategy, with empirical evidence showing that the proportion of annuals is greater in hot, arid, or variable climates. Crucially, introduced species, a group that disproportionately includes annuals, are expanding in number and range across the globe. Whether introduced richness is governed by the same climatic controls as native richness remains untested at continental scales. For 19,299 native (12% annual) and 2,802 introduced (34% annual) Australian plant species, we show that native annual richness tracks climate far more tightly than introduced annual richness. Both floras largely follow the global pattern: the annual fraction rises in dry and seasonal climates. However, hotspots of native and introduced annual richness are completely different. Introduced annuals (28% of all annual species) concentrate in wet, populated areas with low precipitation seasonality, whereas native annual richness is fairly evenly distributed, with the highest diversity in the seasonal tropics. The current continental-scale pattern is thus the sum of a long interaction between the native floras life histories and in situ climate, with dynamic, path-dependent introductions layered on top. As introductions and range expansions continue, they will reshape the annual-to-perennial balance along pathways of human influence.

ecology↗

bioRxiv2021

AusTraits: a curated plant trait database for the Australian flora

We introduce the AusTraits database - a compilation of measurements of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 375 traits across 29230 taxa from field campaigns, published literature, taxonomic monographs, and individual taxa descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological parameters (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual-, species- and genus-level observations coupled to, where available, contextual information on site properties. This data descriptor provides information on version 2.1.0 of AusTraits which contains data for 937243 trait-by-taxa combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data to increase our collective understanding of the Australian flora.

ecology↗

bioRxiv2020

Sex and Power: sexual dimorphism in trait variability and its eco-evolutionary and statistical implications

Biomedical and clinical sciences are experiencing a renewed interest in the fact that males and females differ in many anatomic, physiological, and behavioral traits. Sex differences in trait variability, however, are yet to receive similar recognition. In medical science, mammalian females are assumed to have higher trait variability due to estrous cycles (the estrus-mediated variability hypothesis); historically in biomedical research, females have been excluded for this reason. Contrastingly, evolutionary theory and associated data support the greater male variability hypothesis. Here, we test these competing hypotheses in 218 traits measured in >26,900 mice, using meta-analysis methods. Neither hypothesis could universally explain patterns in trait variability. Sex-bias in variability was trait-dependent. While greater male variability was found in morphological traits, females were much more variable in immunological traits. Sex-specific variability has eco-evolutionary ramifications including sex-dependent responses to climate change, as well as statistical implications including power analysis considering sex difference in variance.

evolutionary biology↗

bioRxiv2018

What we (don’t) know about global plant diversity

RationaleThe era of big biodiversity data has led to rapid, exciting advances in theoretical and applied biological, ecological and conservation sciences. While large genetic, geographic and trait databases are available, these are neither complete nor random samples of the globe. Biases in species absence in these databases create problems, reducing our inferential and predictive power.\n\nMethodsWe performed a comprehensive examination of the taxonomic and spatial sampling in the most complete current databases for plant genes, locations, and traits.\n\nResultsOnly 17.7% of the worlds described land plants feature in all three databases, meaning that more than 82% of plant biodiversity lacks representation in at least one database. Species coverage is highest for location data and lowest for genetic data. Bryophytes and orchids stand out taxonomically and the equatorial region stands out spatially as poorly represented in all databases.\n\nConclusionWe have highlighted a number of clades and regions about which we know little functionally, spatially and genetically, on which we should set research targets. The scientific community should recognize and reward the significant value, both for biodiversity science and conservation, of filling in these gaps in our knowledge of the plant tree of life.

ecology↗

bioRxiv2018

Symbiont switching and alternative resource acquisition strategies drive mutualism breakdown

Cooperative interactions among species, termed mutualisms, have played a crucial role in the evolution of life on Earth. However, despite key potential benefits to partners, there are many cases where two species cease to cooperate, and mutualisms break down. What factors drive the evolutionary breakdown of mutualism? We examined the pathways towards breakdowns of the mutualism between plants and arbuscular mycorrhizal (AM) fungi. Using a comparative approach, we identify ~25 independent cases of complete mutualism breakdown across global seed plants. We found that breakdown of cooperation was only stable when host plants either: (i) partner with other root symbionts or (ii) evolve alternative resource acquisition strategies. Our results suggest that key mutualistic services are only permanently lost if hosts evolve alternative symbioses or adaptations.\n\nSignificance StatementCooperative interactions among species - mutualisms - are major sources of evolutionary innovation. However, despite their importance, two species that formerly cooperated sometimes cease their partnership. Why do mutualisms breakdown? We asked this question in the partnership between arbuscular mycorrhizal (AM) fungi and their plant hosts, one of the most ancient mutualisms. We analyse two potential trajectories towards evolutionary breakdown of their cooperation, symbiont switching and mutualism abandonment. We find evidence that plants stop interacting with AM fungi when they switch to other microbial mutualists or when they evolve alternative strategies to extract nutrients from the environment. Our results show vital cooperative interactions can be lost - but only if successful alternatives evolve.

evolutionary biology↗