m Declaration I declare that this work contains no material which has been accepted for the award of any other degree or diploma in any university or other tertiary institution and, to the best of my knowledge and belief contains no material previously published or writl+n by another person, except where due reference has been made in the text' I also give consent to this thesis being available for photocopying and loan if accepted for the award of the degree. Abstract I investigate the

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... nce mechanisms of Erodiophyllum elderi, a short lived and land daisy which inhabits low-lying areas in the north-east of South Australia. The topography of this region results in a series of E. elderi patches which vary in shape and size and are separated by distances of up to 10's of kilometres. Erodiophyllum elderi produces flowers which develop into hard woody capitula containing up to 130 seeds. Persistence mechanisms are investigated in terms of life history strategies and patcþ population theory. Patcþ population theory suggests that populations which are spread over space may have increased persistence if there is some degree of asynchrony between population fluctuations and if dispersal between populations occurs. Erodiophyllum elderi populations had highly syrchronous dynamics due to similar environmental conditions over large areas. Results from this study indicate two persistence mechanisms operating on different time scales. Firstþ, the seedhead allows within-patch, between generation persistence. Secondly, large dispersal events with infrequent deluges of rain may disperse seedheads between patches akin to the theoretical predictions of patcþ population models. Such dispersal events which are only likely to occur every century of so, may enable temporally extinct populations to be recolonised. However, such effects remain pweb speculative at this stage. There are many people who have made this research possible. Without them I woulC not havebeenabletoundertake such an tmportant life journey. Some people are lucky to have one good supervisor, I was very lucþ io have three excellent ones. Althougheachone of them tnlariated and exasperated me at some stage durtngmy PhD, I am sure it was insignificant comparcd with how they felt. Their spatiotemporal dynamics lead to temporal extinctions, competition and co-existence. Thank you to:José M. Facelli (for coming to Koonamore atleast once, even if the field componenthad already finished) , Peter Chesson (for almost gefting his hands dirty in the field) and Hugh Possingham (for winning me a chocolate fuog). Your academic input, diversity, enthusiasm and friendship over the years is greatly appreciated. I was fortunate to receive a Science Facuþ Scholarship from the University of Adelaide and a Collaborative Research Scholarship from the Research School of Biological Sciences atThe AustraltanNational University. By some miracle I also received funding to altendThe Special Year tnMathematical Biology, Ecology andEvolufion semester at the University of tJtah and the MathematicalBiology Summer School atThe University of British Columbia. The most rmportant people, the ones that helped me in the field, in the lab, with compr:fers and withou t them, those that have made my life bearable in the last few years by giving me m ny warmhugs andbuckets of support: lemeryrLadd,Mum and Bþles were there whenever I wanted or needed them, even if it was a weekend and they were very tiredl Others cameto Koonamore atleast once, some retutnedralTwere appreciated: the 1996 KVR [workingl p^rty. A special thanks to all who wrote entertaining comments and drew spectacular drawings in my databooks. Michael and Amandawatered all those cute liftle daisies in the glasshouse with chocolate as the ot:Jy payment. Academtc gurdance came from all. over the world. Through no fault of their own, these people patiently put up with my daisy yabberings at some stage: provided reassuring comments in the last couple of weeks and suggested the alternattve tttle: What's a plant like you doing in a place like this? LachlanM*Lachlan allowed access to the Koonamore pastorallease, and provided alot of insight into sheep and daisies (althoughl am still not sure which bits to believe O). Russ Sinclair andDavtdLadd alTowed,encouraged and trusted me to use Bindy-i coltage, Koonamore Yegetation Reserve, and the associated records. I doubtthat this thesis wouldhave come to fruition without the encouragementrhelp and laughter fuomJemeryDay and Wendy Telfer duringthose difficult writing months. Jarrah provided an excellent distraction from writing my thesis. Frnally,I would like to extend my greatest appreciation and admtration to TGBO forhaving the insþht to establish such a wonderful experiment so many yeaß ago and for spacing the verandãhposts so that ahammockfits so well between theml The reserve andBindy-rhave become a r'ery special place for many of us who have worke d tn the Botany Department, The University of Adelatde. I am luclçy to have spent such an tmportant part of my life there. With friends Ihave shared some very special times. 3.3.2 Densities of grasses, forbsarrdE. elderi 3.3.3 Population dynamics of Erodiophyllum elderi 3.3.4 Seed density and seedhead age class structure 3.4 DISCUSSION J 4 7 7