Yep - metagenomics/phylogenomics practitioners have learned the hard way that trying to focus on species definitions gets you nowhere (if you think defining a s

Yep - metagenomics/phylogenomics practitioners have learned the hard way that trying to focus on species definitions gets you nowhere (if you think defining a species in multicellular sexually reproducing eukaryotes is hard, wait till you see what bacteria do - it's basically a free-for-all; and on top of that, short read metagenetic DNA sequencing gives you a soup of DNA that is very hard to precisely partition by source). I consider the focus on species and speciation to be a science social phenomenon more than anything else, a lot of it attributable to the prestige of being the one to "discover" the species (a.k.a. describe it in a way that sticks). The flipside is that the science of phylogenomics is incredibly fruitful, in that as we collect more complete information about genomes and their diversity and patterns of conservation, we are able to better understand life in all of its forms. It's also very data intensive and computationally complex - some of the most sophisticated data compression, suffix tree construction, hashing, and clustering algorithms are used in this field. An unsung group of heroes in the face of this insane complexity is the scientists at NCBI whose job it is to organize all of the taxonomic and reference genetic/genomic sequence information (they are the ones who build the GenBank, RefSeq, and NCBI Taxonomy databases). Their work is as close as it comes to the source of truth on this. While the GenBank FTP server is easily overwhelmed by modern workloads trying to ingest this data, AWS and GCP provide high throughput mirrors (https://aws.amazon.com/opendata/ https://aws.amazon.com/opendata/, s3://ncbi-blast-databases, gs://blast-db).