Repeated patterns in the evolution of size in island plants

10.26686/wgtn.17151437.v1 ◽

2021 ◽

Author(s):

◽

Matthew Biddick

Keyword(s):

Functional Traits ◽

Large Scale ◽

Plant Traits ◽

Leaf Size ◽

Plant Functional Traits ◽

Common Element ◽

Island Rule ◽

Island Populations ◽

Stem Size ◽

Island Evolution

For reasons not fully understood, animals often evolve predictably on islands. For example, radiations of large, flightless birds are a common element of many island biotas. However, our understanding of how plants evolve on islands is comparatively poor. Further, an investigation into the evolution of island plants could help resolve unanswered questions about island animals. This thesis investigates insular size changes in a range of plant functional traits. First (Chapter 2), I explored size changes in 9 species of vines that have colonized islands from the New Zealand and Australian mainland. I asked whether leaf–stem allometry prohibits leaves and stems from evolving independently from one another. Island populations consistently produced larger leaves than did mainland populations. Moreover, changes in leaf size were not associated with concomitant changes in stem size, suggesting that trait allometry does not govern trait evolution on islands. Next (Chapter 3), I asked whether plants obey the infamous island rule, a putative trend in island evolution wherein small animals become large on islands and large animals become small. I demonstrate that plant stature and leaf area obey the island rule, and seed size does not. My findings illustrate that the island rule is more pervasive than previously considered, but that support for its predictions vary among plant functional traits. Third (Chapter 4), I demonstrate that the island rule results from evolutionary drift along bounded trait domains. The island rule has long been hypothesized to result from a suite of selective pressures. Applying my model to island plants, I show that evolutionary drift is the most parsimonious explanation for the island rule pattern. Finally (Chapter 5), to explore insular patterns in leaf size evolution, I conducted a large-scale, macroevolutionary analysis of leaf size on 98 of New Zealand’s offshore islands. Leaf gigantism was emblematic of island populations, and was most prominent in taxa with variable leaf morphologies on the mainland. Further, leaf gigantism was greatest in populations inhabiting old, distant islands, suggesting that time since divergence is a direct predictor of morphological differentiation between mainland and island populations. Overall, this thesis reveals novel patterns, and helps disentangle the distinct roles of natural selection and drift, in the evolution of plant form and function on islands. Finally, this thesis illustrates how investigating the changes in plant traits can help identify the evolutionary mechanisms operating on islands.

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New handbook for standardised measurement of plant functional traits worldwide

Australian Journal of Botany ◽

10.1071/bt12225 ◽

2013 ◽

Vol 61 (3) ◽

pp. 167 ◽

Cited By ~ 1438

Author(s):

N. Pérez-Harguindeguy ◽

S. Díaz ◽

E. Garnier ◽

S. Lavorel ◽

H. Poorter ◽

...

Keyword(s):

Functional Traits ◽

Environmental Changes ◽

Plant Traits ◽

Leaf Traits ◽

Plant Functional Traits ◽

Trophic Levels ◽

Evolutionary Patterns ◽

Ecosystem Properties ◽

Species Invasions ◽

Wide Range

Plant functional traits are the features (morphological, physiological, phenological) that represent ecological strategies and determine how plants respond to environmental factors, affect other trophic levels and influence ecosystem properties. Variation in plant functional traits, and trait syndromes, has proven useful for tackling many important ecological questions at a range of scales, giving rise to a demand for standardised ways to measure ecologically meaningful plant traits. This line of research has been among the most fruitful avenues for understanding ecological and evolutionary patterns and processes. It also has the potential both to build a predictive set of local, regional and global relationships between plants and environment and to quantify a wide range of natural and human-driven processes, including changes in biodiversity, the impacts of species invasions, alterations in biogeochemical processes and vegetation–atmosphere interactions. The importance of these topics dictates the urgent need for more and better data, and increases the value of standardised protocols for quantifying trait variation of different species, in particular for traits with power to predict plant- and ecosystem-level processes, and for traits that can be measured relatively easily. Updated and expanded from the widely used previous version, this handbook retains the focus on clearly presented, widely applicable, step-by-step recipes, with a minimum of text on theory, and not only includes updated methods for the traits previously covered, but also introduces many new protocols for further traits. This new handbook has a better balance between whole-plant traits, leaf traits, root and stem traits and regenerative traits, and puts particular emphasis on traits important for predicting species’ effects on key ecosystem properties. We hope this new handbook becomes a standard companion in local and global efforts to learn about the responses and impacts of different plant species with respect to environmental changes in the present, past and future.

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The island rule and its application to multiple plant traits

10.26686/wgtn.17136800 ◽

2021 ◽

Author(s):

◽

Annemieke Hendriks

Keyword(s):

Plant Traits ◽

Leaf Size ◽

Small Islands ◽

Small Species ◽

Island Rule ◽

Petiole Length ◽

Island Endemics ◽

Species Pairs ◽

Size Diversity ◽

Plant Stature

The Island Rule refers to a continuum of body size changes where large mainland species evolve to become smaller and small species evolve to become larger on islands. Previous work focuses almost solely on animals, with virtually no previous tests of its predictions on plants. I tested for (1) reduced floral size diversity on islands, a logical corollary of the island rule and (2) evidence of the Island Rule in plant stature, leaf size and petiole length. Endemic island plants originated from small islands surrounding New Zealand; Antipodes, Auckland, Bounty, Campbell, Chatham, Kermadec, Lord Howe, Macquarie, Norfolk, Snares, Stewart and the Three Kings. I compared the morphology of 65 island endemics and their closest ‘mainland’ relative. Species pairs were identified. Differences between archipelagos located at various latitudes were also assessed. Floral sizes were reduced on islands relative to the ‘mainland’, consistent with predictions of the Island Rule. Plant stature, leaf size and petiole length conformed to the Island Rule, with smaller plants increasing in size, and larger plants decreasing in size. Results indicate that the conceptual umbrella of the Island Rule can be expanded to plants, accelerating understanding of how plant traits evolve on isolated islands.

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Corrigendum to: New handbook for standardised measurement of plant functional traits worldwide

Australian Journal of Botany ◽

10.1071/bt12225_co ◽

2016 ◽

Vol 64 (8) ◽

pp. 715 ◽

Cited By ~ 56

Author(s):

N. Pérez-Harguindeguy ◽

S. Díaz ◽

E. Garnier ◽

S. Lavorel ◽

H. Poorter ◽

...

Keyword(s):

Functional Traits ◽

Environmental Changes ◽

Plant Traits ◽

Leaf Traits ◽

Plant Functional Traits ◽

Trophic Levels ◽

Evolutionary Patterns ◽

Ecosystem Properties ◽

Species Invasions ◽

Wide Range

Plant functional traits are the features (morphological, physiological, phenological) that represent ecological strategies and determine how plants respond to environmental factors, affect other trophic levels and influence ecosystem properties. Variation in plant functional traits, and trait syndromes, has proven useful for tackling many important ecological questions at a range of scales, giving rise to a demand for standardised ways to measure ecologically meaningful plant traits. This line of research has been among the most fruitful avenues for understanding ecological and evolutionary patterns and processes. It also has the potential both to build a predictive set of local, regional and global relationships between plants and environment and to quantify a wide range of natural and human-driven processes, including changes in biodiversity, the impacts of species invasions, alterations in biogeochemical processes and vegetation–atmosphere interactions. The importance of these topics dictates the urgent need for more and better data, and increases the value of standardised protocols for quantifying trait variation of different species, in particular for traits with power to predict plant- and ecosystem-level processes, and for traits that can be measured relatively easily. Updated and expanded from the widely used previous version, this handbook retains the focus on clearly presented, widely applicable, step-by-step recipes, with a minimum of text on theory, and not only includes updated methods for the traits previously covered, but also introduces many new protocols for further traits. This new handbook has a better balance between whole-plant traits, leaf traits, root and stem traits and regenerative traits, and puts particular emphasis on traits important for predicting species' effects on key ecosystem properties. We hope this new handbook becomes a standard companion in local and global efforts to learn about the responses and impacts of different plant species with respect to environmental changes in the present, past and future.

Download Full-text

A handbook of protocols for standardised and easy measurement of plant functional traits worldwide

Australian Journal of Botany ◽

10.1071/bt02124 ◽

2003 ◽

Vol 51 (4) ◽

pp. 335 ◽

Cited By ~ 2078

Author(s):

J. H. C. Cornelissen ◽

S. Lavorel ◽

E. Garnier ◽

S. Díaz ◽

N. Buchmann ◽

...

Keyword(s):

Plant Species ◽

Functional Traits ◽

Atmospheric Chemistry ◽

Large Scale ◽

Predictive Power ◽

Environmental Changes ◽

Plant Traits ◽

Research Effort ◽

Ecosystem Responses ◽

Large Numbers

There is growing recognition that classifying terrestrial plant species on the basis of their function (into 'functional types') rather than their higher taxonomic identity, is a promising way forward for tackling important ecological questions at the scale of ecosystems, landscapes or biomes. These questions include those on vegetation responses to and vegetation effects on, environmental changes (e.g. changes in climate, atmospheric chemistry, land use or other disturbances). There is also growing consensus about a shortlist of plant traits that should underlie such functional plant classifications, because they have strong predictive power of important ecosystem responses to environmental change and/or they themselves have strong impacts on ecosystem processes. The most favoured traits are those that are also relatively easy and inexpensive to measure for large numbers of plant species. Large international research efforts, promoted by the IGBP–GCTE Programme, are underway to screen predominant plant species in various ecosystems and biomes worldwide for such traits. This paper provides an international methodological protocol aimed at standardising this research effort, based on consensus among a broad group of scientists in this field. It features a practical handbook with step-by-step recipes, with relatively brief information about the ecological context, for 28 functional traits recognised as critical for tackling large-scale ecological questions.

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The island rule and its application to multiple plant traits

10.26686/wgtn.17136800.v1 ◽

2021 ◽

Author(s):

◽

Annemieke Hendriks

Keyword(s):

Plant Traits ◽

Leaf Size ◽

Small Islands ◽

Small Species ◽

Island Rule ◽

Petiole Length ◽

Island Endemics ◽

Species Pairs ◽

Size Diversity ◽

Plant Stature

The Island Rule refers to a continuum of body size changes where large mainland species evolve to become smaller and small species evolve to become larger on islands. Previous work focuses almost solely on animals, with virtually no previous tests of its predictions on plants. I tested for (1) reduced floral size diversity on islands, a logical corollary of the island rule and (2) evidence of the Island Rule in plant stature, leaf size and petiole length. Endemic island plants originated from small islands surrounding New Zealand; Antipodes, Auckland, Bounty, Campbell, Chatham, Kermadec, Lord Howe, Macquarie, Norfolk, Snares, Stewart and the Three Kings. I compared the morphology of 65 island endemics and their closest ‘mainland’ relative. Species pairs were identified. Differences between archipelagos located at various latitudes were also assessed. Floral sizes were reduced on islands relative to the ‘mainland’, consistent with predictions of the Island Rule. Plant stature, leaf size and petiole length conformed to the Island Rule, with smaller plants increasing in size, and larger plants decreasing in size. Results indicate that the conceptual umbrella of the Island Rule can be expanded to plants, accelerating understanding of how plant traits evolve on isolated islands.

Download Full-text

Fungal phylogenies and plant functional traits structure root associated fungal networks in a subtropical forest

10.22541/au.160583596.66076333/v1 ◽

2020 ◽

Author(s):

Chunchao Zhu ◽

Zihui Wang ◽

Wenqi Luo ◽

Jiayi Feng ◽

Yongfa Chen ◽

...

Keyword(s):

Functional Traits ◽

Root Morphology ◽

Mycorrhizal Fungi ◽

Host Plants ◽

Plant Traits ◽

Dark Respiration ◽

Plant Functional Traits ◽

Dry Matter Content ◽

Fungal Phylogeny ◽

Fungal Interactions

Rhizosphere fungi are essential for plant survival and ecosystem functioning, but the processes structuring plant-fungal interactions remain largely unknown. We constructed association networks between 43 plant species and two groups of root-associated fungi (mycorrhizal and pathogenic) using sequence data. We revealed modularity within the association networks using network analysis, and correlated this modular structure with functional traits and phylogenetic history driving plant-fungal interactions. We observed strong modularity in both plant-mycorrhizal fungal and plant-pathogenic fungal association networks. Plant functional traits and fungal phylogeny clustered within modules. Host plants of mycorrhizal fungi differed significantly between modules in terms of their leaf dry matter content, photosynthetic traits and root tissue density. Host plants of pathogenic fungi differed significantly between modules in terms of their dark respiration rate, light compensation point and root morphology. Modularity within fungi was a product of fungal phylogeny, whereas host plant modularity was a product of functional traits (leaf morphology, photosynthetic rate and root morphology). Our study illustrates the link between plant functional traits and fungal assembly, and highlights the importance of niche-based processes in shaping plant-fungus association networks. Our results suggest that plant traits may be instrumental in managing the composition of belowground fungal communities.

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