Yes, its true, we can classify on differents way, but we need to analyse them, which one we must to use, also for teach. I am more accord with Keeling Patrick, I want to see your opinions about this topic.

Thank you

I strongly disagree with their convention to list all taxa alphabetically. In almost every case there is a wealth of phylogenetic data showing that the taxa listed in adjacent positions in their linear classification are actually not closely related.

An example from birds: Psittaciformes (parrots and allies) is now known to be the sister taxon of Passeriformes (the songbirds), but these are not listed next to each other in this classification. Any classification that does not reflect such knowledge, is not going to be taken seriously by specialists and is doing a disservice to its (non-specialist) end-users.

And even if taxa are correctly placed next to each other in a list of multiple taxa, they could not be placed in a separate taxon because the relevant rank was not used by the authors. For instance, Archosauria (the clade containing crocodiles and birds) could not be recognized. Thus, the new classification disregards a huge body of knowledge because the authors limited their endeavor to a small number of ranks.

This is a classification of living organisms but it is unlear how extinct clades can be accomodated in this system. This is not a trivial issue given that >95% of taxa are extinct. For instance, Aves (birds) is listed as a subclass of Reptilia, but there is no indication how the large number of splits in the phylogeny between the origin of Reptilia and the origin of Aves are going to be ranked.

Another problem is how sister taxa are listed. If two taxa are sisters, current practice (albeit mostly implicit) is to list the smallest clade before the largest. In ornithology, ALL modern authors place Palaeognathae (ostriches, kiwis, etc) before Neognathae ('modern' birds) because the former is the smaller clade. In the classification by Ruggiero et al. (2015), the order is reversed because N comes before P in the alphabet. I doubt that anyone in ornithology is going to use this.

This could have been avoided (i) if the ambitions of the authors were a bit higher, (ii) if the level of detail (structure) of the classification was based on actual phylogenetic knowledge, rather than a small set of ranks, (iii) and if the authors had sought the help from specialists.

A rankless system (i) would have given the authors the freedom to recognize additional clades and resulted in a much better reflection of current phylogenetic knowledge, and (ii) avoided pointless 'debate' about the 'appropriate' rank of any given taxon.

However, even with a ranked system much more could have been done with all the phylogenetic knowledge that is already available.

The classification by Ruggiero and colleagues is only an attempt, nice in the way it is proposed but not representing a global consensus one. For instance, in some groups, if we focus the attention on certain taxonomic categories (even classes, certainly orders and minor ones) we are far from having a consensus. The proposed classification also needs to be emendend, as some recent studies have pointed out new phylogenetic aspects for some groups (e.g., Kinorhyncha, Priapulida, but also others).

I totally agree with other comments in saying that the alphabetical listing adopted by the authors needs to be rejected by people studying the phylogenetic aspects of the living being, and, I would say, by taxonomists. The classification can not be detached from the present phylogenetic knowledge. 

In this point of view, the reported example regarding birds is among the more evident limits of this classification, but to me also the position of some "minor" animal phyla (e.g., Kinorhyncha, Priapulida, Gastrotricha, and others) within the classification makes nonsense.

More in general, I believe that this feature is definitely misleading and confusing more than helpful for people who want, e.g., to catch a first closer glimpse to the world of organisms classification.

Dear George and Matteo

Thank you very much for your views, give us much analysis, I agree that we need to correlate the phylogeny, and cladistic with taxa. In any case beyond using an alphabetic list, we can maybe use a cladogram, so be clearer (like those used Keeling, Patrick), for example as far as I knew that the animals and fungi are more closely related than fungi to the plants; The chlorophyta also originate seed plants, etc., so everything we see here is linear, like if everyone were in the same evolutionary level. It is also important to add those groups that were forgotten or have recently been described, for example within the group of gymnosperms, they forgot to place some groups.

I see that could be a good contribution is the attempt of equivalence between supergroup taxa (clades unnamed floating) with those of the Kingdom, but could be improved by placing the phylogeny based on her competence. In order to use classification as a reference, we need to see the evolutionary process.

Anyway it is a step, we must continue giving up. Now would be better than this undergo discussion with specialists in the field. 

I hope not last many years until there is a consensus that this creates many problems, many Internet sites stopped updating their databases for these issues and most are with rankings of 2007 at best, like Tree of Life Web Project  and others.

I do not understand why one need all the time to redo taxonomy? It only confuses researchers and gives nothing new to biology. In recent years, the system of organisms altered many times. Now it is almost impossible to determine not only the species and the genus of the specimens, but more higher rank up to kingdom. Anyway Nature is richer than any classification. Where, for example, include lichens: to the kingdom of plants or to the kingdom of fungi? Is euglena an animal or a plant? Such examples are numerous. As a result, reviewers often reject the articles just because they have a different view on taxonomy. It is better don't change the classification and use of the old one, more or less established.

Thus, I do not agree with the classification of living things of Ruggiero et al. 2015.

As Richard Dawkins said: Who cares?

Indeed. If you look where is the greatest biodiversity, you will see that it is not the place, where a taxonomic group originates, as suggested by Vavilov, but the place where a taxonomist walks.

It is true and difficult to classify organisms who are having simbiosis, I think that a lichen have to be taken account like separate, algae and fungi species.

I think (in my opinion) that It is, and it was a necessity having a classification, but I am not accord using the typical 5 or 6 kingdoms (plant, fungi, protist, and others), I prefers use the groups like SAR, Unikonts, Archaeplastida, etc.

Also is true that many times is very difficult to define species, and sometimes I imagine in 50 years, we could have problems with the binomial names, you know that there are many species that have the second name repeatedly in many names?, like Taraxacum officinale, and other ones that also have officinale; could we found more than something specific like subspecies? how can we do calling with 3, 4 names? Cannis lupus familiaris. So i think that maybe for now we can work with Genus.

So Lets proposed keep talking and giving solutions, I know that the nature have a very powerfull way of been, that we cant classify perfectly, because about the many patterns it have.

Let's remember why it is necessary to have a consensus classification? Why do we classify? let's try to represent in the best possible way the integrity of nature.

I think that Ruggiero et al.'s work is a nice attempt to stabilize the classication. I like the fact that it is not a cladist classification. Supergroups are nonsensical, they don't accurately catch the macroevolutionary leaps in eukaryotic evolution. This system of 2 empires and 7 kingdoms is a clever one, but I think there are too many phyla, especially in bacteria and in animals. The use of traditional names like Plantae and Heterokonta instead of respectively Archaeplastida and Stramenopiles is a good thing. However, I find it very strange that birds are considered reptiles ? Maybe some cladists are responsible for this absurdity.