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Amphibian Systematics

Thursday, Jul 12, 2018 amphibians, barcoding, systematics, R

Amphibian Systematics A great deal of work needs to be done to update the taxonomy and systematics of African amphibians and to gain a deeper understanding about aspects of their natural history. Recent years, perhaps fuelled by the proliferation of molecular barcoding techniques coupled with phylogenetic and coalescence species delimitation methods, have seen a surge in systematic revisions and newly described species. Together with many colleagues, I have contributed to furthering our understanding of species, their distributions and tadpole morphology for a number of African amphibians.

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Developmental Plasticity

Thursday, Jul 12, 2018 transcriptomics, pelobates

Larval Plasticity Developmental plasticity is a common adaptation to environmental heterogeneity and understanding the evolution of such plasticity is an important goal in evolutionary biology. Amphibian larvae are usually capable of accelerating their development in response to pond drying to avoid desiccation risk, with the Western Spadefoot toad (Pelobates cultripes) being an extreme example. This species can accelerate its development by more than 30%! The Gomez Mestre Group is currently working on uncovering the gene regulatory network underlying this plasticity, by experimentally induce early development through simulated pond drying and screen the transcriptome for differentially expressed genes.

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Genome Size Evolution

Thursday, Jul 12, 2018 amphibians, comparative phylogenetics

Genome Size Evolution Genomes of different organisms vary hugely in size. Most of this difference is not linked to organism complexity, but instead, in the amount of non-coding DNA. Whether or not life history traits affect the evolution of the physical size of genomes is unclear. On a cellular level, large genomes impose physiological rate limits and processes like cell proliferation and differentiation are significantly slower. This is particularly important for amphibians, which have some of the largest genomes of all known vertebrates and many undergo complex life history transitions that involve both rapid growth as well as cell and tissue differentiation.

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