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Acclimatisation and Adaptive Capacity of Sea Urchins in a Changing Ocean

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Acclimatisation and Adaptive Capacity of Sea Urchins in a Changing Ocean COPYRIGHT AND USE OF THIS THESIS This thesis must be used in accordance with the provisions of the Copyright Act 1968. Reproduction of material protected by copyright may be an infringement of copyright and copyright owners may be entitled to take legal action against persons who infringe their copyright. Section 51 (2) of the Copyright Act permits an authorized officer of a university library or archives to provide a copy (by communication or otherwise) of an unpublished thesis kept in the library or archives, to a person who satisfies the authorized officer that he or she requires the reproduction for the purposes of research or study. The Copyright Act grants the creator of a work a number of moral rights, specifically the right of attribution, the right against false attribution and the right of integrity. You may infringe the author’s moral rights if you: - fail to acknowledge the author of this thesis if you quote sections from the work - attribute this thesis to another author - subject this thesis to derogatory treatment which may prejudice the author’s reputation For further information contact the University’s Copyright Service. sydney.edu.au/copyright Acclimatisation and adaptive capacity of sea urchins in a changing ocean: Effects of ocean warming and acidification on early development and the potential to persist Shawna Andrea Foo A thesis submitted to the University of Sydney in fulfillment of the requirements for the degree of Doctor of Philosophy Department of Anatomy and Histology, University of Sydney November 2015 TABLE OF CONTENTS ACKNOWLEDGEMENTS ......................................................................................... VI ABSTRACT ................................................................................................................. VII CHAPTER 1 – General Introduction ............................................................................ 1 1.1 Climate change ............................................................................................................ 1 1.2 The impact of climate change on the oceans ............................................................... 1 1.2.1 Ocean change in Eastern Australia ........................................................................... 2 1.3 Impacts of ocean change stressors on the gametes and fertilization of free spawning marine invertebrates .......................................................................................................... 4 1.3.1 Impacts on Spermatozoa ........................................................................................... 5 1.3.2 Impacts on Eggs ..................................................................................................... 13 1.3.3 Impacts on Fertilisation .......................................................................................... 15 1.3.3.1 Effects of ocean stressors on individual male-female pairs ................................ 16 1.3.3.2 Effects of ocean stressors on a spawning population as determined with multiple males and females ............................................................................................................ 19 1.3.3.3 Impacts on calcifying and non-calcifying larvae ................................................ 20 1.4 Identifying gaps in ocean change studies .................................................................. 26 1.5 The potential to persist in the face of climate change: Acclimatisation and adaptation ........................................................................................................................ 26 1.5.1 Acclimatisation ....................................................................................................... 27 1.5.1.1 Acclimatisation and thermal tolerance limits ...................................................... 30 1.5.1.2 Phenotypic plasticity and genetic assimilation ................................................... 32 1.5.2 Adaptation .............................................................................................................. 33 1.5.2.1 Evidence of standing genetic variation ............................................................... 34 1.5.2.2 Evolutionary rescue ............................................................................................. 35 1.5.2.3 Human assisted evolution .................................................................................... 36 1.5.3 Reaction norms and visualization of genotype by environment interactions ......... 37 1.6 Assessing evolutionary potential in a changing ocean .............................................. 37 1.6.1 Use of quantitative genetic designs with free spawning marine invertebrates ....... 37 1.6.2 Clonal studies ......................................................................................................... 42 1.6.3 Laboratory selection experiments with short generation species ........................... 45 II 1.6.4 Genetic correlations; interactions across multiple environments ........................... 48 1.6.5 Heritability .............................................................................................................. 51 1.7 Transgenerational effects ........................................................................................... 52 1.8 Multigenerational Effects .......................................................................................... 56 1.9 Epigenetics ................................................................................................................ 57 1.10 Thesis outline ........................................................................................................... 58 1.10.1 Aims ..................................................................................................................... 59 CHAPTER 2 – Changes in the jelly coat of echinoid eggs in response to acidification, could this drive variation in fertilisation assays? ................................ 60 2.1 Abstract ...................................................................................................................... 60 2.2 Introduction ............................................................................................................... 60 2.3 Methods ..................................................................................................................... 62 2.3.1 Study species, collection sites and spawning procedure ........................................ 62 2.3.2 Experimental conditions ......................................................................................... 63 2.3.3 Jelly coat experiments ............................................................................................ 63 2.3.4 Statistical analyses ................................................................................................. 65 2.4 Results ....................................................................................................................... 65 2.4.1 Comparison of the egg and jelly coat size within species ...................................... 65 2.4.2 Effects of ocean acidification on jelly coat size ...................................................... 67 2.4.3 Echinometra mathaei .............................................................................................. 67 2.4.4 Heliocidaris tuberculata ......................................................................................... 67 2.4.5 Centrostephanus rodgersii ..................................................................................... 67 2.4.6 Heliocidaris erythrogramma .................................................................................. 72 2.5 Discussion .................................................................................................................. 72 2.5.1 Conclusions ............................................................................................................ 75 CHAPTER 3 – Contributions of genetic and environmental variance in early development of the Antarctic sea urchin Sterechinus neumayeri in response to increased ocean temperature and acidification .......................................................... 76 3.1 Abstract ...................................................................................................................... 76 3.2 Introduction ............................................................................................................... 77 3.3 Materials and methods ............................................................................................... 79 3.3.1 Study species and collection sites ........................................................................... 79 III 3.3.2 Fertilisation and the North Carolina II design ...................................................... 79 3.3.3 Experimental conditions – temperature and pH treatments ................................... 80 3.3.4 Statistical analyses ................................................................................................. 83 3.4 Results ....................................................................................................................... 83 3.4.1 Cleavage stage embryos ......................................................................................... 83 3.4.2 Blastulae ................................................................................................................. 83 3.4.3 How does performance at the blastula stage compare
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