The Tree We Share: Building the Tree of Life for Biodiversity, Ecology, and Conservation

We share one tree – the Tree of Life – through our shared evolutionary history with all known living organisms. Building the tree of life is also an immense collaborative enterprise undertaken by biologists worldwide. Cheaper and faster access to genetic data – from DNA barcoding to phylogenomics – has led to a rapid expansion of phylogenetic information over the past 20 years. Phylogenetic trees act as time machines that we can use to infer and account for past evolutionary history. They are therefore pivotal for classifying biodiversity but also for modern evolutionary biology, ecology and conservation. 

After a brief introduction on the concept of phylogenetic trees, I will present several examples primarily drawn from my own work, to illustrate why and how we integrate phylogenetic information to address a wide variety of questions. Specifically, I will present examples of macroevolutionary studies, to reconstruct past evolutionary history of morphological and ecological traits such as body size, body shape, species interactions. I will also show how phylogenetic information informs biodiversity conservation, from prioritization to understanding species’ sensitivity to global changes. 

In the second part, I will put into perspective the phylogenetic data and tools available nowadays to discuss our current state of knowledge of the Tree of Life, as well as our limitations in generating large-scale trait datasets. I will highlight progress in phylogenetics over the past 20 years and the challenges that remain for faster expansion of the tree of life. I will finish by presenting an ongoing project of using a global scale insect monitoring program and metabarcoding for discovering and classifying new taxa, and crucially for expanding the Tree of Life by orders of magnitude. I will also show an example of how we are trying to scale up acquisition of phenotypes for large-scale sampling programs.