There are several models of the branching order of bacterial phyla, one of these is the Genome Taxonomy Database (GTDB). The GTDB is an initiative to establish a standardised microbial taxonomy based on genome phylogeny, primarily funded by an Australian Research Council Laureate Fellowship. The genomes used to construct the phylogeny are obtained from RefSeq and Genbank, and GTDB releases are indexed to RefSeq releases, starting with release 76. Importantly and increasingly, this dataset includes draft genomes of uncultured microorganisms obtained from metagenomes and single cells, ensuring improved genomic representation of the microbial world. All genomes are independently quality controlled using CheckM before inclusion in GTDB.