L-G-0008029621-0015322853.Pdf
Total Page：16
File Type：pdf, Size：1020Kb
The Giraffe The Giraffe Biology, ecology, evolution and behaviour Bryan Shorrocks Environment Department University of York Heslington, York United Kingdom This edition first published 2016 © 2016 by John Wiley & Sons, Ltd Registered Office John Wiley & Sons, Ltd, The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK Editorial Offices 9600 Garsington Road, Oxford, OX4 2DQ, UK The Atrium, Southern Gate, Chichester, West Sussex, PO19 8SQ, UK 111 River Street, Hoboken, NJ 07030‐5774, USA For details of our global editorial offices, for customer services and for information about how to apply for permission to reuse the copyright material in this book please see our website at www.wiley.com/wiley‐blackwell. The right of the author to be identified as the author of this work has been asserted in accordance with the UK Copyright, Designs and Patents Act 1988. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher. Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The publisher is not associated with any product or vendor mentioned in this book. Limit of Liability/Disclaimer of Warranty: While the publisher and author(s) have used their best efforts in preparing this book, they make no representations or warranties with respect to the accuracy or completeness of the contents of this book and specifically disclaim any implied warranties of merchantability or fitness for a particular purpose. It is sold on the understanding that the publisher is not engaged in rendering professional services and neither the publisher nor the author shall be liable for damages arising herefrom. If professional advice or other expert assistance is required, the services of a competent professional should be sought. Library of Congress Cataloging‐in‐Publication Data Names: Shorrocks, Bryan, 1943– author. Title: The giraffe : biology, ecology, evolution and behaviour / Bryan Shorrocks. Description: Chichester, UK ; Hoboken, NJ : John Wiley & Sons, 2016. | Includes bibliographical references and index. Identifiers: LCCN 2016025833| ISBN 9781118587478 (cloth) | ISBN 9781118587461 (epub) Subjects: LCSH: Giraffe. Classification: LCC QL737.U56 S56 2016 | DDC 599.638–dc23 LC record available at https://lccn.loc.gov/2016025833 A catalogue record for this book is available from the British Library. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. Set in 8.5/12pt Meridien by SPi Global, Pondicherry, India 1 2016 Contents Preface, vi 1 Introduction to the giraffe, 1 2 Origins, 13 3 Present distribution and geographical races, 26 4 Anatomy, 42 5 Physiology, 60 6 Individual behaviour, 76 7 Individual ecology, 100 8 Social networks, movement and population regulation, 134 9 Conservation status and wildlife reserves, 166 References, 187 Index, 217 v Preface Robert H. MacArthur was an American ecolo- pacing gait and, it should be stressed, is not gist at Princeton University who, in the 1960s unique to the giraffe, being found in the okapi and early 1970s, made a major impact on many (Okapia johnstoni), camel (Camelus dromedarius), areas of community and population ecology. His llama (Lama glama), topi (Damaliscus lunatus emphasis on hypothesis testing helped change jimela), kongoni (Alcephalus buselaphus), wilde- ecology from a primarily descriptive field into beest (Connochaetes taurinus), hyaena (Crocuta an experimental field, and drove the development crocuta) and some canids, all with sloping backs. of theoretical ecology. When he wrote his final Look for patterns first, and then within these book, Geographical Ecology (1972), he began the general patterns look again at giraffes and how introduction with these words: they might differ. Of course, patterns can be misinterpreted, To do science is to search for repeated patterns, not simply particularly if several quite different causes can to accumulate facts. produce the same pattern. Researchers must This present book is about the giraffe, but I hope consider all options as an explanation and try it is not simply a collection of facts. Of course, and eliminate those for which evidence is lack- there are many facts about giraffes in the book, ing. Naturally, conservationists are frequently but I have also attempted to look for patterns. involved in non‐scientific discussions, often And sometimes this has involved reanalysing involving local ‘feelings’ about animals and older data and using data from other species. their livestock and crops, but when collecting There are two main reasons for the latter. First, data and drawing conclusions they must always some areas of giraffe biology are poorly docu- use the ‘tried and tested’ protocols of the scientific mented. Therefore looking at other African method. browsers, or even other ungulates, might provide I would like to thank several people who an insight into what giraffes are doing, and sug- have provided permissions, thoughts, photo- gest research areas that require more attention. graphs and encouragement for my work on Second, even if we have the data for giraffes, it giraffes. These include: Fred Bercovitch, Rachel is essential to examine what other African Brand, Kerryn Carter, Mike Chase, Isobelle browsers/ungulates are doing in order to see if Ciofolo, John Doherty, Jack Lennon, Zoe there is in fact a general pattern. Muller, Mordecai Ogada, Russell Seymour and Many enthusiasts who write about giraffes Robert Sutcliffe. In addition, I thank Dan frequently say that this ‘piece of biology is Rubenstein for discussions, at the Mpala unique to the giraffe’. But here lies a danger. If Research Centre in Kenya, on his zebra stripe we only look at giraffes and see everything they patterns that gave me the idea for the giraffe do as unique to them, then we will always codes in Chapter 8. I thank Roger Butlin for search for answers by looking only at giraffes. d iscussions about species and DNA, and I thank For example, giraffes are frequently said to have Craig Hilton‐Taylor, Head of the IUCN Red List a unique fast gait in which the legs on the same Unit, for permission to quote extensively from side of the body move forward together. The IUCN publications and their website. I thank ‘unique’ is not true. This type of gait is called a Darren Croft for introducing me to ‘social vi Preface vii n etworking ideas’ and to Paul Ward for reintro- Safaris, in Nairobi, for being so helpful during ducing me to Africa. Finally, I thank the staff at over 20 years of visits to their country, and pro- the Mpala Research Centre in Laikipia, Kenya, viding me with vehicles. I thank the Kenyan and Etosha National Park, Namibia, for all their Ministry of Education, Science and Technology kind help during my stays there. for providing me with research permits. Most of my work has been centred in Kenya, where I also took MSc students for many years. Bryan Shorrocks I thank all the staff and drivers at Concorde January 2016 Chapter 1 Introduction to the giraffe In the prehistoric rocky landscape of the Sahara, Namibia and Mozambique in the south (Le native people drew pictures of this amazing ani- Quellec 1993, 2004; Muzzolini 1995). Wherever, mal, and in the Egyptian Bronze Age it deco- in fact, there has been savannah. However, the rated the tombs of kings. It may even have been most extensive and remarkable rock art is found the god the Egyptians called ‘Set’ (Spinage in areas of the Sahara (Coulson & Campbell 1968a). In ancient Greece and Rome it was 2001). Today these are found in remote, inhos- called the ‘camelopard’, in East Africa today it is pitable regions of the desert, so arid that any twiga, and in the English language we now call form of sustained human or animal existence is it ‘giraffe’. The name ‘giraffe’ has its earliest untenable today. They document prehistoric known origins in the Arabic word zarafa cultures that apparently thrived in these regions, (zarāfah) ( ), perhaps from some African hunting wild animals and herding domesticated language. The name can be translated as ‘fast cattle, that have subsequently vanished, leaving walker’ (Kingdon 1997), although some lin- little trace of their presence or of the richness of guistic authorities believe it stems from a source their cultures. meaning an ‘assemblage of animals’. Clearly, The Sahara has not always been the desert it the Greeks took this latter view. They contrib- is today. Over the last 2 million years, it has fluc- uted part of its scientific name, camelopardalis, tuated several times between even greater which literally describes a camel’s body wearing aridity and plentiful rain. Where there are now a leopard’s coat. The Italian form giraffa arose in dry gullies, rivers once flowed. In what are now the 1590s and the modern English form devel- empty sandy plains, there were lakes sur- oped around 1600 from the French girafe. The rounded by grasslands and trees, rather like the old and the new now combine to form the savannahs of sub‐Saharan Africa today. The giraffe’s scientific name, Giraffa camelopardalis, earliest rock art, much of which represents large although interestingly, the form ‘kameelperd’ wild animals such as giraffe, hippo, elephant, survives in Afrikaan. rhinoceros and the extinct long‐horned buffalo In one form or another, giraffes have been (Buffalus antiquus), is believed to have been cre- around for a very long time. And so has Homo ated by hunter‐gatherers more than 7000 years sapiens.