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Full Version: Species: Doing away with the most "important" (and ambiguous?) concept in biology
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http://theconversation.com/what-is-a-spe...ery-119200

EXCERPT: A koala bear isn’t actually a bear, it’s a marsupial. Whales aren’t fish, they’re mammals. Tomatoes aren’t vegetables, they’re fruit. Almost nothing is actually a nut. Peanuts, Brazil nuts, cashews, walnuts, pecans and almonds: none of them are really nuts (for the record, peanuts are legumes, Brazils and cashews are seeds, and the others are all drupes). Hazelnuts and chestnuts are the exception: they are the elite, the “true” nuts.

We’ve all heard facts like this before. [...] They reflect an area of science known as biological taxonomy, the classification of organisms into different groups. At the core of this area lies the notion of the species. The basic idea is very simple: that certain groups of organisms have a special connection to each other.

[...] This is only the tip of a deep and confusing iceberg. There is absolutely no agreement among biologists about how we should understand the species. One 2006 article on the subject listed 26 separate definitions of species, all with their advocates and detractors. Even this list is incomplete.

The mystery surrounding species is well-known in biology, and commonly referred to as “the species problem”. Frustration with the idea of a species goes back at least as far as Darwin. [...] He proposed that one day, biologists could pursue their studies without ever worrying about what a species is, or which animals belong to which species. Indeed, some contemporary biologists and philosophers of biology have taken up this idea, and suggested that biology would be much better off if it didn’t think about life in terms of species at all.

Scrapping the idea of a species is an extreme idea: it implies that pretty much all of biology, from Aristotle right up to the modern age, has been thinking about life in completely the wrong way. The upshots of this new approach would be enormous [...] It suggests that we should give up thinking about life as neatly segmented into discrete groups. Rather, we should think of life as one immense interconnected web. This shift in thinking would fundamentally reorient our approach to a great many questions concerning our relation to the natural world, from the current biodiversity crisis to conservation. (MORE - details)
Species, like race, is a classification of shared traits. Getting rid of the notion is postmodernist nonsense.
It isn't just species. The 'higher' taxa are also difficult to pin down and define. An order or class or genus in one taxonomic lineage may not name the same sort of distinctions as the same word in a different lineage. It all becomes kind of arbitrary anyway, when it's remembered that the 'tree-of-life' has millions of branches. There just aren't enough categories ('genus'. 'class', 'order', 'phylum' etc.) to to handle them all. Certainly not in any consistent manner.

There are lots of conceptual problems in taxonomy, even now.

Here's a short survey of the development of taxonomy over the last 200 years or so, including a bit of an explanation of the motivation for 'rank-free' classification towards the end.

http://ib.berkeley.edu/courses/ib200/rea...Taxon).pdf

Some philosophical (as opposed to technical-biological) books on the subject of problems in the philosophy of biological classification

The Species Problem

https://www.amazon.com/Species-Problem-C...49-6743865?

Biological Classification - A Philosophical Introduction

https://www.amazon.com/Biological-Classi...1107687845

The Species Problem - Biological Species, Ontology and the Metaphysics of Biology

https://www.amazon.com/Species-Problem-B...073910778X

Carving Nature at its Joints - Natural Kinds in Metaphysics and Science

https://www.amazon.com/Carving-Nature-It...0262516268