Dispar
The Online Journal of Lepidoptera
ISSN 2056-9246
The Online Journal of Lepidoptera
ISSN 2056-9246
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This book presents a readable account of butterfly behaviour, based on field observations, great photographs and the latest research. The main focus is on courtship and mating - including perching, searching and territorial behaviour - but to understand these subjects it is necessary to explain how mates are chosen and this requires sections on wing colours and patterns. A chapter on butterfly vision is also essential in terms of how butterflies see the world and each other. There have been exciting discoveries in all of these fields in recent years, including: butterfly vision (butterfly photoreceptors), wing patterns (molecular biology), wing colouration (structural colours and nano-architecture), mating strategies and female choice (ecology and behaviour).
The book has hard covers, with a glossy paper covering. The 384 pages are perfectly bound, which is usually used for cheap paperbacks, to be read once and thrown away. This means that the book does not open flat, even when opened at the centre. It is disappointing that the publishers have chosen a cheap binding for such an expensive book.
In the preface, Raymond Cannon states that he is not a lepidopterist by profession, but has spent his working life studying insects, and only became interested in butterflies later in life, following on from an interest in photography. He has spent 3 years on the project studying the published literature, and the book is the result of his labours. In his summing up, he states that he has tried to be entertaining as well as educative.
There are photographs of most of the butterflies discussed in the book, including some of set specimens. Each photograph has full credits in the caption, which perhaps would have been better placed in a separate section at the end of the main contents, as they becoming distracting. Most of the photographs are of perched butterflies, rather than any feature relevant to the location, courtship or mating of the butterflies.
Chapter 1 provides an introduction to the superfamily Papilionoidea. The book covers butterflies worldwide, but is mainly confined to butterflies of Europe, Japan, and North America. Both common names and scientific names are provided, but authorities are not provided, and the reader has to consult the references at the end of each chapter. There is a preference for using sub-specific names throughout the book, although the rationale for this is unclear. The chapter then discusses some of the earlier works on butterfly courtship behaviour.
Chapter 2 covers sexual selection and mate choice. A section discusses mate selection, asking whether it is the female prerogative. While in some species it clearly is, in others the female has no choice. Identification of a potential mate in butterflies is initially by sight. Butterflies use visual signals to identify each other. But the discussion on structural colours is left to chapter 10, which seems out of place, and the material is better located next to chapter 2.
Chapter 3 covers the strategies for locating a mate, which is divided into perching and patrolling. The book unexpectedly does not cover when butterflies come to sexual maturity. For example, Meadow Browns will mate soon after eclosion, whereas Brimstones only become sexual active after hibernation. This will have an impact on the mate location strategy that the butterfly deploys, as the female Meadow Browns will be in their natal habitat, whereas the female Brimstone will have dispersed, and will have to be searched over a large area in the spring. The book does not explain why a butterfly might switch mate location strategy, such as in the case of the male Purple Emperor which attempts to find freshly emerged females amongst the sallows in the mornings, and when that fails goes to a lek (master tree) at mid-day.
Chapter 4 discusses seeing and being seen. The first section is on butterfly colour vision, providing a description of the compound eye, and how the eye gathers light. Three-colour and four-colour vision is discussed and how butterflies can see ultraviolet and polarized light. Female butterflies have photoreceptors in their genitals to aid in egg laying.
Chapter 5 discusses courtship behaviour, where I was expecting a discussion on the use of pheromones. Instead, the chapter provides a brief description for each of the butterfly families of how males flutter around females. The discussion on scents is left to chapter 9, with chapter 6 discussing the body language, such as the mate rejection posture adopted by unreceptive females. There is also a brief description of the Wood White courtship. This all provides a rather disjointed account, and doesn't provide a story of what is going on during courtship.
Chapter 7 is entitled 'The Mating Game. The battle of the sexes, or a tug of war?'. Various mating strategies are discussed, and what happens to pairs in copula.
Chapter 8 is entitled 'The Inside Story'. The section on sperm and spermatophores says that males can provide nuptial gifts of up to 20% of their bodyweight. Unfortunately there is no discussion for why the size of the nuptial gift should vary. For example it is well known that a female Large White can lay up to 700 eggs, and that the only way she can achieve this is by multiple copulations over her life-time, with the males donating a large nuptial gift consisting of proteins and nutrients of up to 20% of their body weight, which the female uses in egg production. For species which only mate once, and lay a small number of eggs, there is no advantage in the males producing a large nuptial gift.
The book does provide over 58 pages of references, which will be useful to anyone new to the field. However, the book does not provide any new information, nor information that cannot be found in greater detail elsewhere.
The list price of the book is £95, available at a discount from various resellers. Overall, I feel that the contents do not justify the cost of the book.