genetic diversity

Mixing fishes and climate change – adaptation by hybridisation

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Adapting to a changing world

The global climate is changing at an unprecedented rate, approaching conditions last seen globally over 3 million years ago. Impacted by the compounding effects of climate change, habitat modification, invasive species and direct exploitation (e.g., fishing and hunting), species across the globe are threatened with extinction. Key to the effective management of global biodiversity is the understanding of how species may (or may not) rise to the challenge of climate change: can species adapt? Which species will adapt? How will they adapt? The answers to these questions are elusive and complicated.

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A tale of two fishes: how standing genetic diversity influences species responses to environmental change

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How can species respond to environmental change?

If you’re a somewhat avid (or even cursory) reader of The G-CAT, you may remember my wrap-up post at the conclusion of my PhD in 2020 which described the various chapters of my thesis. Well, I’m pleased to announce that data chapter 2 of that thesis – on the comparative phylogeography of two threatened Australian freshwater fishes – has just been published in the journal BMC Ecology and Evolution. It’s a pretty complex paper which tackles genetic diversity, phylogenetics, demographic history, species distribution models and how these interact together to understand the evolutionary history of these species in a comparative framework. Feel free to check it out (it’s open access and free to read!) here.

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Conservation applications of functional variation

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From genotype to phenotype

One fundamental aspect of conservation and evolution research is the implicit connection between genetic variation, phenotypic characteristics, and their influence on Darwinian fitness. Genetic diversity underpins many aspects of the adaptive potential of a population, and many of the fundamental concepts of the field rely on the assumed connection between genetic and phenotypic characteristics. But this connection is neither straightforward, nor always predictable.

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Sweeping under the genomic rug: hard and soft sweeps

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Of alleles and selection

If you’ve read this blog more than once before, you’re probably sick of hearing about how genetic variation underlies adaptation. It’s probably the most central theme of this blog, and similarly one of the biggest components of contemporary biology. We’ve talked about different types of selection; different types of genes; different ways genes and selection can interact. And believe it or not, there’s still heaps to talk about! Continue reading →

Products of their time: the impact of demographic history on evolution

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Demographic history

Many things in life are the product of their history, and nothing exemplifies this better than evolution. Given the often-gradual nature of evolution by natural selection, environmental stressors and factors operating on long-term scales (i.e. over thousands or millions of years) can have major impacts on evolutionary changes across the diversity of biota. While many of these are specific to the characteristics of the target organism (i.e. are related to adaptive traits), non-adaptive (neutral) traits are also critically important in driving the path of evolution.

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