This is a collection of survey articles on different aspects of evolutionary biology. A mixed bunch:

• The Evolution of Chemical Signal Receptor Systems: From Slime Molds to Man (John Tyler Bonner)

  The title is a bit inaccurate: the essay really only discusses simple chemical receptor systems (in particular those of slime molds), and the author's claim that the nervous systems of higher animals are only quantitatively different seems more than a little dubious.

• Evolutionary Origins of Sex (L. Margulis and D. Sagan)

  So you thought you knew all the different kinds of sex? Well what about these:

  Amixis - absence of meiosis and fertilisation at any stage in the life cycle

  Automixis - syngamy or karyogamy of nuclei or sells derived from the same parent

  Arrhenotoky - parthenogenetically produced haploid males and amphimictically produced diploid females

  Tychoparthogenesis - occasional partheogenesis

  The basic argument is that sexual processes come in a very wide variety of kinds and are separate from reproduction in most taxa. The difficulty is not explaining the evolution of sex — different sexual processes have evolved multiple times, and have been lost multiple times. It is not strange that almost all 'higher' vertebrates use gametic meiosis, what is strange is that so few of them have reverted to asexuality. The explanation offered is that due to historical developments sex has become so closely linked to reproduction, embryology and development that it is now an indispensable part of the life cycle.

• Deception, the way of all flesh, firefly signalling and systematics (James E. Lloyd)

  This is really two separate essays: a extensive catalogue of deception in assorted species and a discussion of firefly signalling. The catalogue is interesting but the viewpoint seems dominated by Dawkins' idea that all communication is based on deception. The discussion of firefly behaviour is really interesting — the author clearly knows what he is talking about and the details are quite amazing.

• Two Ways to be a Tropical Big Moth: Santa Rosa Saturniids and Spingids (Daniel H. Janzen)

  This is a description of large tropical moths in a Central American national park. It covers the details of ecological niches, mating strategies, life histories, and in a brief conclusion describes how these are relevant to the evolutionary history and population genetics of the taxa in question. I think the extensive tables of data could (and should) have been omitted (this is the longest essay in the book), but the colour photos are attractive. Very readable (perhaps surprisingly considering the rather specific subject).

• Size Inequalities and Fitness in Plant Populations (Otto T. Solbrig and Dorothy J. Solbrig)

  Not terribly exciting. Basically a discussion of the reasons for particular size distributions in plant populations.

• Multilocus Dynamics (Michael T. Clegg)

  This is the most mathematical of the essays in the book. The primary topic is the extent to which epistasis (interactive effects between different loci undergoing selection) is important in understanding the dynamics of population gene frequencies. Some simple models for linkage disequilibrium, hitchhiking selection and associative overdominance are discussed with particular attention to empirically verifiable predictions.

• Hierarchy and evolution (Niles Eldredge and Stanley N. Salthe)

  A philosophical and very (too?) formal attempt to describe a hierarchical theory of evolution, as an alternative to the "modern neo-Darwinian synthesis". Too complicated to understand after one reading!

• Narrow Approaches to Phylogeny: A Review of Nine Books of Cladism (Michael T. Ghiselin)

  This is an attack on excessively narrow approaches to phylogeny. The books reviewed all represent cladistic approaches to phylogeny that use only narrow anatomical characteristics and refuse to use data from ecology, molecular genetics, evolutionary history, or other disciplines. The point made is that phylogenetics, as well as being used by these disciplines, can and should use them in return. Much of the problems of cladistic phylogeny is shown to be due to a failure to understand the fundamental difference between classes and individuals.

I found most of these essays really intriguing, though I may need to reread the Eldredge and Salthe paper.

June 1992

Related reviews:

- books by Richard Dawkins
- books about evolution
- books published by Oxford University Press