An Introduction to the Invertebrates

Transcription

1 An Introduction to the Invertebrates Janet Moore New Hall, Cambridge niustrations by Raith Overhill Second Edition. :::.. CAMBRIDGE :: UNIVERSITY PRESS

2 ~nts ao Paulo, Delhi rcss, New York._ MOO 586 List of boxes preface Acknowledgements mustration acknowledgements Chapter I The process of evolution: natural selection What was Darwin's theory of natural selection? What was Mendel's theory of heredity? What is the cellular basis of heredity? What is the origin of genetic variation? What is _the pature of genes? What.is tht;; role of chance in evolution? At what level does natural selection act? Wha't iii general does evolution produce?. ~' ' page xi xiii XV xvii Library Chapter 2 I The pattern of evolution: methods of investigation How should we classify animals? How can we use morphology to trace phylogeny? How can we use fossils to investigate phylogeny? Can the fossil record date the earliest appearance of animals? How can we use molecules to trace phylogeny? Which molecules are used? How is molecular information obtained? How is molecular information processed? How reliable is molecular taxonomy? What is the present state of phylogenetic enquiry? 22 or red to in ~bsitcs is, Chapter 3 I Porifera 3.1 What are the distinguishing characters of sponges? 3.2 What different kinds of sponge are known? 3.3 How do sponges make a living? 3.4 What changes have evolved during sponge history? 3.5 How are sponges related to other phyla? 3.6 How have sponges become so successful? Chapter 4 I Cnidaria 4.1 Why do we regard Cnidaria as simple? 4.2 What kinds of Cnidaria are known? 4.3 How do Cnidaria make a living? 4.4 How has so much diversity been possible?

3 vi ~ 4.5 What is the ecological importance of coral reefs? 4.6 How are Cnidaria related to each other and to other phyla? Chapter 5 I On being a worm 5.1 Why are there so many different kinds of worm? 5.2 How can muscles move a worm? 5.3 What worm phyla are known? 5.4 Do Ctenophora belong among the worms? Chapter 6 I Platyhelminthes and Acoelomorpha 6.1 What is the body plan of the platyhelminths? 6.2 What groups of worms constitute the Platyhelminthes? 6.3 What are the Acoelomorpha? 6.4 What is specialised about modern platyhelminths? 6.5 How are platyhelminths related to each other? 6.6 How are platyhelminths related to other phyla? Chapter 7 I Nemertea 7.1 What are the principal groups of nemertines? 7.2 How do nemertines resemble platyhelminths? 7.3 How do nemertines differ from platyhelminths? 7.4 What diversity exists among nemertines? 7.5 How do nemertines develop? 7.6 How are nemertines related to other phyla? Chapter 8 I Nematoda 8.1 What are the distinctive characters of nematodes? 8.2 How are these characters related to the cuticle and fluid pressure? 8.3 How is the phylum subdivided? 8.4 Why are nematodes useful for developmental studies? 8.5 Why has Caenorhabditis elegans been studied so thoroughly? 8.6 How are nematodes related to other animals? 8.7 Conclusion Chapter 9 I Annelida 9.1 What is an annelid? 9.2 What annelids are there? 9.3 What are the advantages of the coelom and of metamerism? 9.4 How does a coelom introduce complexity? 9.5 How do annelids reproduce and feed? How ar 9.7 How ar Chapter Conclus 10.1 What is 10.2 How ca 10.3 What is 10.4 What a What a What is Gastropoda 10.7 How is How rna 10.9 Why are Chapter II l1 in Scapl:i in Cepha What ha: What are Bivalvia 11.1 How is t 11.2 What is 11.3 How do 11.4 What ki1 Scaphopoda 11.5 How is ti Cephalopoda 11.6 How is 11.7 What Ce 11.8 How is N 11.9 How hav; Chapter 12 1 ~ 12.1 What det 12.2 What are 12.3 How are 12.4 What rna 12.5 What are Chapter IJJ C What is d 13.2 What are 13.3 How have 13.4 What rna:

4 ? s? udies? How are annelids related to each other? How are annelids related to other phyla? ~pter 101 Mollusca: general and Gastropoda What is the basic molluscan body plan? How can such an animal function? What is the shell and how may it be used? 10.4 What are the main groups of molluscs? 1o.s What are the Aculifera? 1 o.6 What is unusual about the Monoplacophora? Gastropoda 1o.7 How is the molluscan body plan modified in gastropods? 10.8 How may gastropods feed? 10.9 Why are many gastropods hermaphrodites? Conclusion Chapter II 1 Mollusca: Bivalvia and Cephalopoda Bivalvia 11.1 How is the molluscan body plan modified in bivalves? 11.2 What is the range of bivalves? 11.3 How do bivalves feed? 11.4 What kinds of muscle are there in bivalves? Scaphopoda 11.5 How is the molluscan body plan modified in Scaphopoda? Cephalopoda 11.6 How is the molluscan body plan modified in Cephalopoda? 11.7 What Cephalopods are lmown? 11.8 How is Nautilus able to survive? 11.9 How have some cephalopods become so active? What has limited the evolution of cephalopods? What are the evolutionary relationships of molluscs? Chapter 121 Arthropoda: general vii What defines an arthropod? 12.2 What are the key features of arthropod cuticle? 12.3 How are arthropod internal cavities organised? 12.4 What makes possible the great activity of arthropods? 12.5 What are the closest relations of arthropods? Chapter Il l Crustacea 13.1 What is distinctive about crustaceans? 13.2 What are the main kinds of crustacean? 13 3 How have crustaceans colonised fresh water and land? What may limit the size of Crustacea?

5 viii 13.5 What are the special features of parasitic crustaceans? 13.6 What is the role of crustacean larvae? 13.7 How are Crustacea related to each other? Chapter 141 Chelicerata and Myriapoda F --- ' Hemichord 18.4 Wha 18.5 Wha in co 18.6 Wher deut Chelicerata 14.1 What are chelicerates? 14.2 Why is Limulus of special interest? 14.3 What are pycnogonids? 14.4 What are arachnids? 14.5 How did arachnids colonise the land? Myriapoda 14.6 What are myriapods and how do they move? 14.7 How well are myriapods adapted to life on land? Chapter IS I Insecta 15.1 What is an insect? 15.2 Why are insects such successful land animals? 15.3 How are insects able to fly? 15.4 What is distinctive about insect life cycles? 15.5 What are the main orders of insects? 15.6 How could social behaviour have evolved? 15.7 Why has study of the fruit fly Drosophila been so important? Chapter 161 Animals with lophophores 16.1 What is a lophophore? 16.2 Which animals have lophophores? 16.3 Are animals with lophophores protostomes or deuterostomes? 16.4 What are the relationships of Entoprocta? 16.5 Should there be a group called 'Lophophorata'? Chapter 171 Echinodermata Chapter 1 develc What What Cond 19.1 How 19.2 Wha 19.3 Wha 19.4 How 19.5 How 19.6 How 19.7 What 19.8 What 19.9 Howe Chapter 2( for e\1 the ea withii Concl 20.1 Howe 20.2 Howl 20.3 Howe 20.4 What 20.5 Howe 20.6 When 20.7 Howe 20.8 What 20.9 Can\\ 17.1 What is unique about echinoderms? 17.2 What is unusual but not unique about echinoderms? 17.3 How do different echinoderms feed and move? 17.4 Do the larvae illuminate echinoderm evolution? Further readi; Glossary Index Chapter lsi Invertebrate Chordata and Hemichordata Chordata 18.1 What are the chordate characters? 18.2 Which are the invertebrate chordates? 18.3 How are the invertebrate chordates related?

6 eans? 177 J-{emichordata What are the hemichordates? '5 What do enteropneusts and pterobranchs have 18.? in common. 243 Where do the hemichordates fit in to the deuterostomes? 244 Chapter 1 Development How do animals develop? What makes different animals develop differently? What is the pattern of cleavage in invertebrates? How do invertebrates gastrulate? How is polarity established? How do cells acquire positional information? What happens in later development? What can studies of regeneration tell us about 192 development? How do genes regulate development? What are Hox genes and how do they work? What is 'evo-devo'? Conclusion Chapter 20 I Invertebrate evolutionary history How can we trace the course of evolution? How have genes provided enough raw material for evolution? How can genes help us to trace evolution? What do genes tell us about relationships between the earliest phyla? How do genes relate the protostome phyla? Where do the smaller protostome phyla fit in? How do genes relate the deuterostome phyla? What do molecules tell us about relationships 219 within phyla? Can we now define homology? Conclusion Further reading 283 erms? 224 Glossary Index 313? 232 ix ta