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Thesis Rests with Its Author University of Bath PHD Activity patterns and organization within ant nests Hatcher, Melanie J. Award date: 1992 Awarding institution: University of Bath Link to publication Alternative formats If you require this document in an alternative format, please contact: [email protected] General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Download date: 08. Oct. 2021 Activity Patterns and Organization Within Ant Nests submitted by Melanie J. Hatcher for the degree of PhD of the University of Bath 1992 COPYRIGHT Attention is drawn to the fact that copyright of this thesis rests with its author. This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with its author and that no quotation from the thesis and no information derived from it may be published without the prior written consent of the author. This thesis may be made available for consultation within the University Library and may be photocopied or lent to other libraries for the purposes of consultation. UMI Number: U050955 All rights reserved INFORMATION TO ALL USERS The quality of this reproduction is dependent upon the quality of the copy submitted. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if material had to be removed, a note will indicate the deletion. Dissertation Publishing UMI U050955 Published by ProQuest LLC 2014. Copyright in the Dissertation held by the Author. Microform Edition © ProQuest LLC. All rights reserved. This work is protected against unauthorized copying under Title 17, United States Code. ProQuest LLC 789 East Eisenhower Parkway P.O. Box 1346 Ann Arbor, Ml 48106-1346 rsIITV OF SATH Abstract I develop an automated technique for measuring positional change, and employ this system to measure short term patterns of activity in laboratory nests of the ant species Leptothorax acervorum and L. tubero-interruptus. Individuals of these species appear to synchronize their activity such that cycles in colony activity level occur at approximately 20 minute intervals for L. acervorum and 35 minutes for L. tubero-interruptus. Using a combination of manual and automated techniques, I test a number of models designed to account for short term activity cycles in ant nests. The results do not support the predictions of Goss and Deneubourg (1988) or Hemerik et al. (1990), but are broadly in agreement with the predictions of Tofts (1990a). I investigate the behaviour and activity patterns of individuals of L. acervorum , and demon­ strate a division of labour in this species. The two task groups indentified appear to differ in their activity profiles, cycling in activity at different rates, and leading to a complex pattern of activity at the colony level. I investigate the effect of food deprivation on colony and individual activity, and demonstrate that colony activity cycles are maintained, although individuals shift their activity profiles as food deprivation continues. I employ automated techniques to investigate the strength of coupling of activity levels between different regions of the nest, and to investigate patterns of activity in differing physical designs of nests. I discuss a number of models designed to account for the adaptive significance of the observed patterns of activity in ant nests. Acknowledgements I would like to thank Nigel Franks for his tolerance and support throughout my studentship. I am indebted to Chris Tofts for his mathematical and technical input, without which the science herein would not equate to knowledge, and for his constant efforts to teach me to see. I am sincerely grateful to Bath’s technical staff; Jim, Jackie, Pete, Mollie, Dave and Tim, without whom none of us could function. To my colleagues, friends and family for their support, discussion and for going to the pub at short notice, thank you Sanj, Tim, Janice, Dominique, Mat and Paul, and all occupants of the 6 West cupboard. I dedicate this work to Michael and Erica for their emotional and financial support throughout my life. This work was funded by the SERC. C ontents 1 Introduction 7 1.1 Approaches to the study of social insects ........................................... 7 1.2 A im s ........................................................................................................... 10 1.3 Self Organization and Mass A ction .................................................... 13 1.4 The Nature of Interactions .................................................................... 18 1.5 Patterns of Activity in Ant N ests .......................... 20 1.6 Leptothorax acervorum: behaviour and ecology ....................... 22 1.6.1 E v o lu tio n ..................................................................................... 22 1.6.2 E c o lo g y ........................................................................................ 24 1.6.3 Polygyny ..................................................................................... 28 1.6.4 Social p a ra sitism ........................................................................ 30 2 Information Exchange Within Ant Nests 33 2.1 Information Exchange ........................................................................... 33 2.1.1 Communication and Social O rganization ................................ 33 2.1.2 The Concept of Caste .............................................................. 37 2.1.3 Caste: Explanations and Predictions ...................................... 38 2.2 Information Exchange in L. acervorum ................................................ 43 1 2.2.1 Introduction ........................................... 43 2.2.2 Materials and Methods ............................................................... 46 2.2.3 R esults ............................................................................................ 51 2.2.4 D iscussion ..................................................................... 64 3 The Development of an Image Processing System 71 3.1 Introduction: The Principle ................................................................. 71 3.2 Development of an Image Analysis System ....................................... 77 3.2.1 Hardware revision ......................................................................... 78 3.3 Tests of s y s te m ...................................................................................... 79 3.3.1 M eth o d s ......................................................................................... 79 3.3.2 Results............................................................................................. 84 3.3.3 D iscussion ...................................................................................... 86 3.4 Final Version of Image Analysis System .............................................. 88 3.4.1 Hardware ......................................................................................... 89 3.4.2 Software ........................................................................................... 90 4 Activity Patterns Within Ant Nests 96 4.1 Introduction ............................................................................................. 96 4.2 Methods .......................................................................................................101 4.3 Results (Descriptive) ................................................................................ 106 4.3.1 Time S e rie s ......................................................................................106 4.3.2 Turning P o i n t s ............................................................................... 109 4.3.3 Autocorrelation ........................................................ I l l 4.3.4 Other Evidence For Cyclicity ......................................................112 2 4.3.5 Cycle Length Determination ....................................................... 115 4.3.6 Cycle Length Distribution ...........................................................117 4.3.7 Daily Activity L evel .................................................................... 120 4.4 Tests of M odels ........................................................................................... 123 4.4.1 Sim ulation ........................................................................................123 4.4.2 Activity linked to Energy L evel ................................................. 125 4.4.3 Algebraic Description .................................................................... 128 4.5 Discussion ..................................................................................................134 4.5.1 Implications of results for the m odels ........................................134 4.5.2 Data Interpretation
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