Principios de Taxonomia

24j 2 Why is there a Species Problem?
It is very peculiar that a concept such as that of the species has been successfully in
use for centuries, even though it is not consistently defined. Different people, even
scientists, understand different things by the term species. A mammalian species
is something different than a rotifer species or a bacterial species, not on the basis of
content but on the basis of concept. Can the concept of species ever be defined
consistently?
Most people understand a species as a type, a form or a kind. This can be seen
in questions such as what kind of bird is this or what type of butterfly is this, then
or phrases such as two forms of crucifers grow in our garden (Schilthuizen, 2001).
Darwin noted that there is something peculiar about the species concept: it is used
every day, though no one can define what a species is (Darwin, 1859).
This is a highly alarming matter for a scientist. That is, scientists work with species,
and through this they achieve myriad scientifically reproducible results, as evidenced
by thousands and thousands of publications. However, at the same time, they do not
know what species are. Can a scientist, who is pledged to the truth, acquire insight
into an object without knowing what the object is? This must ring a warning bell. The
door seems to be wide open for hunches and instincts, which is dangerous.
Alternatively, is it normal that scientific progress can be achieved using certain
objects without knowing what these objects are?
2.8
The Species as an Intuitive Concept and a Cognitive Preset in the Human Mind
A (European) Blackbird (Turdus merula) is a bird that has a yellow beak and black
plumage. However, there are also albinos or semi-albinos that exhibit either
completely white or partially white plumage. They are still Blackbirds, with no
taxonomist having any doubt about the classification. Interestingly, even laypersons
and experts who have not thought about this problem before do not have any doubt
that the albino Blackbird is a Blackbird. What, then, is a Blackbird? Why do humans
not doubt that even a white Blackbird is a Blackbird?
Humans have held species concepts for as long as we have existed, whether we are
aware of them or not. We classify the nature surrounding us into discrete groups on a
purely intuitive basis. Grouping of organisms was initially merely a matter of
survival. Humans needed to know what predator we had to be wary of and what
berries and fungi we could eat. We use species concepts in everyday life to predict the
properties of organisms and react accordingly. Species concepts are thus everything
but intellectual games of eccentric scientists (Neumann, 2009).
That the various animals and plants in our environment do not constitute an
uninterrupted continuum but belong to distinct groups seems to be a component of
innate human knowledge. Once good or bad experiences have been associated with
an organism, humans are spared going through the same experience a second time
because the conclusion regarding the good or bad properties of the organism is
automatically transferred to a second organism with a similar appearance. We are all
genetically programmed taxonomists. This realization might sound encouraging to