Introducing fishtree and fishtreeoflife.org

This post was originally published on Jonathan Chang’s blog.

In our recent publication (Rabosky et al. 2018) we assembled a huge phylogeny of ray-finned fishes: the most comprehensive to date! While all of our data are accessible via Dryad, we felt like we could go the extra mile to make it easy to repurpose and reuse our work. I’m pleased to report that this effort has resulted in two resources for the community: the Fish Tree of Life website, and the fishtree R package. The package is available on CRAN now, and you can install it with:

install.packages("fishtree")

The source is on GitHub in the repository jonchang/fishtree. The manuscript describing these resources has been published in Methods in Ecology and Evolution (Chang et al. 2019).

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Revisiting Past Biodiversity with the divDyn R Package

Post provided by ÁDÁM T. KOCSIS

The source of occurrence data: fossil collections (Early Jurassic ammonites in the collection of the University of Erlangen-Nuremberg, photo by Konstantin Frisch)

The source of occurrence data: fossil collections (photo by Konstantin Frisch).

To find out about changes in ancient ecosystems we need to analyse fossil databases that register the taxonomy and stratigraphic (temporal) positions of fossils. These data can be used to detect changes of taxonomic diversity and to draft time series of originations and extinctions.

The story would be so simple if it wasn’t the effects of heterogeneous and incomplete sampling: the white spots in our understanding of where and when species lived exactly. This phenomenon decreases the fidelity of face-value patterns extracted from the fossil record, making them less reliable. It must be considered if we want to get a glimpse into the biology or the distribution of life in space and time. Naturally, several metrics have been proposed to overcome this problem, each claiming to accurately depict the patterns of ancient life. Continue reading