Taxonomy is the bedrock of communication about life. If other facets of communication changed, it'd be pretty frustrating, e.g., "from here on, hello will mean mustard". I witnessed the saltiness of taxonomic change first hand in South Africa. Africans had spent their lives calling their iconic, thorny trees Acacia. Acacia even means thorny. That didn't suit taxonomists and all the African acacia were renamed to Vachellia. The non-thorny Aussie trees, of which there were >1,000 species compared to 100-ish in Africa, took the name. Ja, I can see why they'd be salty. In other areas of science, we support or reject hypotheses and move on. Taxonomy is descriptive, hypotheses can be loosely applied (we hypothesise this is a monophyletic group of taxa), but it's a stretch. When two people describe the same piece of art or music, they may differ in their opinion. The same is true for taxonomy. Applying taxonomic ranks to organisms is arbitrary and cases can be made to split or lump any rank at a shared common ancestor. Ultimately, determining gene flow among populations paints a clear picture of species boundaries, but who has the time to do this for millions of fungi. I find it interesting that we become attached to taxonomic names, even when there is evidence to support that they should be called something else. I think we are more emotional because of the vagueness in species/taxon delimitation. In the smut and rust section of this blog, you can read about the taxonomic name for corn smut and why it should be called something other than Ustilago (but jeeze, you'd have to be bored). Clearly even I become emotional about taxonomy. Taxonomic names, as long as they were validly described, are always there for communication and can be used eternally (as long as people know what organism you mean). Just 'cause some fella is saying all the northern hemisphere wood-loving shrooms are Psilocybe subaeruginosa doesn't mean you have to forgo these names. Keep on using them... what do you think African people call acacia (hint: not Vachellia)? The only change here is that we know Australia is the centre of origin of P. subaeruginosa and it has spread to the northern hemisphere where multiple new names have been applied to one taxon. Population diversity illustrated for two species of Psilocybe and several species of Colletotrichum. A. SplitsTree neighbor network based on 382 single copy orthologs identified by OrthoFinder between P. cubensis and P. subaeruginosa. Edge length reflects genetic difference and reticulation is an indication of recombination. B. Network of relatedness among genomes (large circles) and clusters of accessory orthogroups (small grey circles), with nodes and edges coloured by species of Psilocybe. C. SplitsTree neighbor network based on 3,144 single copy orthologs in the Colletotrichum gloeosporioides species complex. The scale is a magnitude smaller than between species of Psilocybe. Long edges radiating from reticulation is a signature of clonal reproduction. A test for the pairwise homoplasy index was 0.0, which indicates randomness of alleles across the alignment and is evidence of reproduction. D. Network of relatedness among genomes (large circles) and 7,989 clusters of accessory orthogroups (small grey circles), with nodes and edges coloured by species of Colletotrichum. Species cluster together to some extent based on their shared accessory genes, however, there is no strong separation of genomes and accessory orthogroups are shared among taxa. The figure illustrates genomic relationships based on core and accessory genes between sister species. For magic mushrooms, the sisters are cubes and subs. Note they are highly separated by core genes and there is almost no overlap of accessory (non-core) genes. Colletotrichum is the other example, and it has been split like a banana in a dessert bar. Note that the core and accessory don't clearly separate species. Likely these are all the same taxon and taxonomists have described clones as different species (which could be acceptable in some instances).
After this explanation, if you still prefer species complexes and lots of names for the same taxon, why not spend your time and resources examining the boundaries of recombination to demonstrate speciation in process?
1 Comment
Alistair
2/15/2024 05:05:49 pm
Re-reading this post a few weeks later, I thought I should clarify a few things.
Reply
Leave a Reply. |
Designer Shrooms @ Funky Fungus on 1st July 2023
I started a gig at Funky Fungus as Chief Scientific Officer to make designer shrooms Our research on Psilocybe
|