The explosive radiation and diversification of the advanced snakes (superfamily Colubroidea) was associated with changes in all aspects of the shared venom system. Morphological changes included... Show moreThe explosive radiation and diversification of the advanced snakes (superfamily Colubroidea) was associated with changes in all aspects of the shared venom system. Morphological changes included the partitioning of the mixed ancestral glands into two discrete glands devoted for production of venom ormucous respectively, as well as changes in the location, size and structural elements of the venom-delivering teeth. Evidence also exists for homology among venom gland toxins expressed across the advanced snakes. However, despite the evolutionary novelty of snake venoms, in-depth toxin molecular evolutionary history reconstructions have been mostly limited to those types present in only two front-fanged snake families, Elapidae and Viperidae. To have a broader understanding of toxins shared among extant snakes, here we first sequenced the transcriptomes of eight taxonomically diverse rear-fanged species and four key viperid species and analysed major toxin types shared across the advanced snakes. Show less
Taxonomy as a science has accumulated data and knowledge for more than 250 years. The quality and usefulness of the facts recorded in taxonomic literature has greatly improved from the early... Show moreTaxonomy as a science has accumulated data and knowledge for more than 250 years. The quality and usefulness of the facts recorded in taxonomic literature has greatly improved from the early descriptive texts to the modern data-rich, hypothesis-driven works. Our work illustrates the application of some of the “e-taxonomic” tools and the “New Taxonomy” thinking explored in the introduction. Here, we analyzed specimen data contained in legacy taxonomic literature in Chapters 2 and 3—to observe species distribution of one spider group and genital evolution, respectively—and also explored an integrative perspective that involves describing new taxa and testing phylogenetic hypotheses using molecular and morphological data, as done in Chapter 4 and 5. Show less
The general aim of the work described in this thesis is to help explain the variation in ageing by using the life history framework of B. anynana. Each chapter focuses on a different aspect of the... Show moreThe general aim of the work described in this thesis is to help explain the variation in ageing by using the life history framework of B. anynana. Each chapter focuses on a different aspect of the life history, together giving a complete picture of the origins of variation in ageing in this species. A central theme to every chapter is the relative influence of genes, the environment, and how they related to plasticity. A summarising discussion of all chapters, and a perspective on how the ideas in this thesis will contribute to ageing research in the future is also included. Show less