iDAPT: ice Dependent Adaptations for Plant Terrestrialization
iDAPT is a four year Leverhulme Trust funded project investigating how the earliest land plants were able to make the fundamental transition from freshwater to terrestrial habitats by examining how a group of closely-related freshwater microalgae are able to thrive in present day icy environments. We believe that ice surfaces represent an important intermediate niche between freshwater and terrestrial environments, and that they played an important role in driving the evolution of biological features required for the historic colonization of land by algae. Through genome sequencing, novel technology development and field expeditions, iDAPT will advance our understanding of how life excels within icy environments and its importance for fundamental transitions in the history of planet Earth. Read on to see the team behind the project, the project rationale, major research objectives, and news.
The iDAPT Team
iDAPT is led by an interdisciplinary team that includes a polar microbiologist, a phytoplankton ecophysiologist, a paleobiologist, an evolutionary biologist and an industrial partner. Click below for links to our individual bios.
Chris Williamson, Lecturer in Polar Microbiology, School of Geographical Sciences, University of Bristol, UK.
Doug Campbell, Professor in Phytoplankton Ecophysiology and Canada Research Chair Tier 1, Mount Allison University, Canada.
Phil Donoghue, Professor of Paleobiology, School of Earth Sciences, University of Bristol, UK.
Tom Williams, Senior Research Fellow, School of Biological Sciences, University of Bristol, UK.
iDAPT Project Rationale
The colonization of land by the earliest land plants was one of the most important steps in the evolution of the Earth, resulting in the world as we know it today. That all land plants evolved from a single, freshwater lineage of microalgae is even more remarkable and raises the question; What was it about the biology of these algae that enabled the conquest of land? Moving from freshwater to terrestrial habitats required tolerance of new extremes in temperature, desiccation, visible and UV-radiation, and the algal ancestor of land plants likely evolved a number of adaptations for some purpose in water, that later proved advantageous on land. We still do not know how or why this environment drove adaptations that facilitated the move onto land.
Glacier algae thrive within surface ice across the cryosphere. (a) Ice camp established at 72oN on the Greenland Ice Sheet to study glacier algal blooms during the summer melt season; (b) Supraglacial surface ice on the southwestern Greenland Ice Sheet heavily colonized by a glacier algal bloom; (c) a heavily pigmented glacier algae assemblage viewed down the microscope showing the major species including the filamentous Ancylonema nordenskiöldii and single-celled Mesotaenium berggrenii.
On the icy surfaces of glaciers and ice sheets, blooms of microalgae occur during summer melt seasons when liquid water and sunlight are available for growth. To survive within this unique icy environment, these so-called glacier algae must tolerate extremes in temperature, desiccation, visible and UV-radiation, key stressors important in the transition of algal life from water to land. Indeed, we believe that ice surfaces themselves represent an important intermediate between aquatic and terrestrial environments, being fundamentally made of water, but subject to terrestrial conditions. The other critical thing about glacier algae; they are amongst the closest living relatives to land plants.
Snowball Earth: iDAPT explores whether conditions prevailing during snowball Earth events were the catalyst for the evolution of biological features that allowed life to jump onto land.
iDAPT explores the idea that snowball Earth events, when the world was covered in snow and ice, were important drivers of adaptations in the algal ancestors of land plants that facilitated the colonization of dry land. By studying how closely related glacier algae are adapted to thrive within icy conditions today, we will identify what adaptations snowball Earth conditions promote in algae, whether these are also found in early land plants, and their role in the transition of life to land.
iDAPT Research Plan
iDAPT is split into three broad areas of research that together allow us to study processes of terrestrialization from the perspective of the cryosphere.
1. Ice dependent exaptations for land plant terrestrialization.
Imperative to advancing knowledge on the importance of the cryosphere for processes of early land plant terrestrialization is obtaining genome information for extant ice environment specialists.
iDAPT will sequence the genomes of specialist Streptophyte glacier algae that dominate across the cryosphere to identify exaptations for the transition of ancestral Streptophytes from aquatic to terrestrial habitats.
2. Monitoring of the bio-cryosphere
Direct quantification of microbial responses to life within ice is imperative to linking the genetic potential of adaptability with actual function. Such measurements have been prevented to-date by a lack of dedicated analytical equipment.
iDAPT will overcome this challenge by working with a leading developer of algal phenotyping platforms (Photon Systems Instruments, Czech Republic) to develop a ‘photosynthetron’ capable of measuring glacier algal responses to life within ice.
3. The role of ice for life
iDAPT will deploy our specially developed photosynthetron across the cryosphere to validate assumptions derived from genome interrogation of ice inhabiting Streptophytes and significantly advance our understanding of the selective pressures driving adaptations within surface ice environments.
Together with our sequenced genomes, these measurements will form our evidence base of how icy environments shape microbial life, and their importance for driving fundamental transitions in Earth’s history.
iDAPT is recruiting its first PDRA: we welcome applications for our first of two 3-year PDRA positions focussing on genomics/bioinformatics of Streptophyte glacier algae. Please see here for the full job advert and details on how to apply. Application deadline is 25th October, with interviews and start date shortly thereafter.