Morphology and development of floral features recognised by pollinators

The diversity of angiosperm flowers is astounding. The conventional explanation for this diversity is that it represents the great variety of ways in which flowers have adapted to attract an even greater diversity of animal pollinators. Many animal behaviourists are therefore interested in how changes in floral morphology affect pollinator behaviour. The establishment of well-characterised model plant species has greatly furthered our understanding of how floral morphology is generated and varied. Many of these model species are pollinated by animals and attract their pollinators through the production of colour, shape, scent, size and rewards. An understanding of the developmental plasticity of floral morphology, and the constraints upon it, should inform research into animal responses to flowers. The use of genetically characterised model species, and the isogenic and near-isogenic lines available in them, will allow dissection of the different components of floral attraction and reward in natural systems. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. Handling editor: Heikki Hokkanen     

Patterns of Singing in the Varied Thrush: I. The Similarity of Songs within Individual Repertoires

I present results in support of the hypothesis that song repertoires of male varied thrushes are organized to reduce stimulus generalization by other birds. The songs are simple tones, modulated in amplitude. Described along two dimensions, dominant frequency (Hz) and period of modulation (ms), the songs within repertoires are less similar than would be expected if they were drawn at random from all the songs in the population. This may enhance the effectiveness of repertoires in repelling other males and in attracting and stimulating females.