I research plant macroecology and macroevolution, and specifically how and why plant diversity varies through time and space. I also work on developing plant-based climate proxies for understanding past climatic and environmental change, and how this in turn drives biodiversity change through time. Most of my research centres on sporomorphs (pollen and spores) as indicators of plant biodiversity and evolution.
My research is currently funded via the DFG-funded project “Sporomorph chemistry, size and morphological disparity: towards a better understanding of the plant fossil record”. This project focuses on integrating extant and fossil palynological records using a range of different parameters, with the aim of developing new tools for understanding floral macroecological and macroevolutionary dynamics.
Below you will find further information about the main things I research, organised into broad categories:
My research is currently funded via the DFG-funded project “Sporomorph chemistry, size and morphological disparity: towards a better understanding of the plant fossil record”. This project focuses on integrating extant and fossil palynological records using a range of different parameters, with the aim of developing new tools for understanding floral macroecological and macroevolutionary dynamics.
Below you will find further information about the main things I research, organised into broad categories:
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Sporomorphs as an indicator of plant palaeobiodiversity change
Sporomorphs are produced by plants in enormous quantities, and since they preserve very well in the geological record, they comprise one of the main parts of the plant fossil record. I'm interested in how we can use this archive better to reconstruct plant biodiversity change through time. I've analysed latitudinal diversity gradients in the greenhouse world of the early Paleogene, and more recently I've started looking at other aspects of biodiversity, such as phylogenetic diversity. I have also recently started entering palynological taxonomic and occurrence data into the Paleobiology Database (https://paleobiodb.org/), in order to examine broad scale floral diversity and biogeographic trends through time. |
Jardine et al. (2018) J. Biogeography
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Sporomorph morphological evolution
Spormorphs have evolved into a wide variety of shapes and sizes, and feature a range of surface sculptures. I'm interested in the evolutionary dynamics that have led to this variety, and testing whether and how we can use specific morphological features (traits) to provide information on past vegetation and environments. I recently published a paper on Asterales (the order that includes daises, thistles, lettuces and bellflowers) pollen morphological diversity and evolution, and I'm currently working on whether pollen size is an informative trait to use in palaeoecological research. |
Jardine et al. (2022) New Phytologist
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Pollen and spore chemistry: a new way of utilising the plant fossil record
The vast majority of research on the fossil pollen record has focused on using the morphological features of pollen grains to tell them apart, and from this infer vegetation change through time. I've been involved in recent research that has shown that this archive can be used in a much more dynamic manner, by leveraging information from the chemical signature of pollen grains. Pollen chemistry incorporates information on both ambient UV-B flux and plant taxonomy, providing a new suite of proxies with which to interrogate the geological record. In the news
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Jardine et al. (2020) The Holocene
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Testing palaeobotanical climate proxies
Recently, I've got interested in testing and validating palaeoclimate proxies that are based on fossil plant remains, and in particular those focused on reconstructing past atmospheric carbon dioxide concentrations. I want to understand better how these proxy measurements are derived, how well they work under different conditions, and whether they can be improved.
Evolution of the US Great Plains mammals
Some research that developed from my MSc project at the University of Bristol, this looked at mammalian evolution in response to changing environments over the last 40 million years. Climatic cooling and drying through this interval led to forest fragmentation and the spread of open grassland environments. The shift from browsing on leaves to grazing on grass was thought to have promoted the evolution of high-crowned (hypsodont) molars in mammals such as horses and camels, because of the higher concentrations of silica bodies (phytoliths) in grasses. By looking at changes in tooth height in both large herbivores and rodents, I showed that the timing of hypsodonty acquisition is more complex than a simple switch to feeding on grasses would suggest, and is more consistent with a response to greater quantities of ingested dust and grit as habitats opened up.
Recently, I've got interested in testing and validating palaeoclimate proxies that are based on fossil plant remains, and in particular those focused on reconstructing past atmospheric carbon dioxide concentrations. I want to understand better how these proxy measurements are derived, how well they work under different conditions, and whether they can be improved.
Evolution of the US Great Plains mammals
Some research that developed from my MSc project at the University of Bristol, this looked at mammalian evolution in response to changing environments over the last 40 million years. Climatic cooling and drying through this interval led to forest fragmentation and the spread of open grassland environments. The shift from browsing on leaves to grazing on grass was thought to have promoted the evolution of high-crowned (hypsodont) molars in mammals such as horses and camels, because of the higher concentrations of silica bodies (phytoliths) in grasses. By looking at changes in tooth height in both large herbivores and rodents, I showed that the timing of hypsodonty acquisition is more complex than a simple switch to feeding on grasses would suggest, and is more consistent with a response to greater quantities of ingested dust and grit as habitats opened up.
