fun fact: i have the conspiracy theory that the USB symbol:
represents the phylogenetic tree of live. there’s a big node right at the beginning which are all the bacteria that aren’t really species (as i explained in another comment in this thread) but groups that can all exchange genes with each other and are therefore “one big species” and a lot of eukaryotic species that a long time ago developed out of them which only branch out, but don’t come back.
in the unlikely case that this is a serious question: yes, there is, at least for eukaryotes.
for eukaryotes (things that have a cellular nucleus) there are “species” which are groups of organisms that can’t produce offspring with each other. The reasons are typically (i think?) that the genetic differences between two species are too great and any offspring would therefore have such a self-incompatible set of genes that they cannot live with.
for prokaryotes (bacteria) the situation is a bit different. due to horizontal gene transfer, they can exchange genes with practically ever other strain of bacteria, as long as the environmental circumstances are right. (and the result is often viable, i.e. the resulting bacteria can live that way). as a consequence, there are not so clearly defined “species” for bacteria. however, there are still groups of bacteria that have a higher similarity to each other, so we still group them together and give them names.
This isn’t generally true for eukaryotes either. In plants, hybridization is a huge thing and also polyploidy. So for some groups of plants we struggle to put them in neat boxes as well.
And zooming out to a larger view on taxonomy, plant taxonomy has seen some huge changes in the last decades with the various APG (angiosperm phylogeny group) publishings rearranging many if not most orders, families and genera of angiosperm plants.
Are there not worthwhile distinctions between sepcies that can interbreed? I remember learning from an anthro professor there are horses for examples that literally have different amounts of chromosomes that can interbreed fine. I still don’t see how ability to have viable offspring isn’t also just an arbitrary distinction I guess, especially when there’s whole classifications of life that break that rule into pieces.
While a little arbitrary, we use “ability to produce viable offspring” as a metric of speciation. Two animals can bone and create an offspring, but that offspring has to have live gametes (egg/sperm) for the parents to be considered the same species.
it’s not that arbitrary as you might think. genetics is literally all about mutating, mixing and recombining genes, and producing viable offspring together is a huge part of that. that is why the concept of species is so important.
We don’t decide the baskets, if any, that this primordial soup decides to branch into.
Real “taxonomy” probably looks more like a web with nodes.
fun fact: i have the conspiracy theory that the USB symbol:
represents the phylogenetic tree of live. there’s a big node right at the beginning which are all the bacteria that aren’t really species (as i explained in another comment in this thread) but groups that can all exchange genes with each other and are therefore “one big species” and a lot of eukaryotic species that a long time ago developed out of them which only branch out, but don’t come back.
Is there such a thing as real taxonomy or are there just different ways to classify life with their own pros, cons, and use cases?
It’s about as artificial as the concept of ‘nations’ I feel
in the unlikely case that this is a serious question: yes, there is, at least for eukaryotes.
for eukaryotes (things that have a cellular nucleus) there are “species” which are groups of organisms that can’t produce offspring with each other. The reasons are typically (i think?) that the genetic differences between two species are too great and any offspring would therefore have such a self-incompatible set of genes that they cannot live with.
for prokaryotes (bacteria) the situation is a bit different. due to horizontal gene transfer, they can exchange genes with practically ever other strain of bacteria, as long as the environmental circumstances are right. (and the result is often viable, i.e. the resulting bacteria can live that way). as a consequence, there are not so clearly defined “species” for bacteria. however, there are still groups of bacteria that have a higher similarity to each other, so we still group them together and give them names.
This isn’t generally true for eukaryotes either. In plants, hybridization is a huge thing and also polyploidy. So for some groups of plants we struggle to put them in neat boxes as well.
And zooming out to a larger view on taxonomy, plant taxonomy has seen some huge changes in the last decades with the various APG (angiosperm phylogeny group) publishings rearranging many if not most orders, families and genera of angiosperm plants.
yeah … plants have hybridization, yeah, i’m still reading into this.
Are there not worthwhile distinctions between sepcies that can interbreed? I remember learning from an anthro professor there are horses for examples that literally have different amounts of chromosomes that can interbreed fine. I still don’t see how ability to have viable offspring isn’t also just an arbitrary distinction I guess, especially when there’s whole classifications of life that break that rule into pieces.
While a little arbitrary, we use “ability to produce viable offspring” as a metric of speciation. Two animals can bone and create an offspring, but that offspring has to have live gametes (egg/sperm) for the parents to be considered the same species.
it’s not that arbitrary as you might think. genetics is literally all about mutating, mixing and recombining genes, and producing viable offspring together is a huge part of that. that is why the concept of species is so important.