Principios de Taxonomia

48j 3 Is the Biological Species a Class or is it an Individual?
the female group. This is an example of a class formation. In contrast, if you see a
single man, you cannot tell whether he is a neighbor. At a minimum, you need a
second individual to make the statement that the first individual belongs to particular
groups. A brother needs at least one sibling to be considered a brother. An outside
observer cannot tell whether an individual is a brother or a father by his intrinsic
traits; information about his relationship to other people is needed (Bock, 1989).
In contrast to class formation, in relational group formation no group member
carries the criteria for group membership within themselves.
The difference between a class formation and a relational group formation can be
explained with a simple example: if many children are playing in an area, and you
want to divide them into groups, there are exactly two options, as explained above
(Figure 2.5). First, you can combine the children into groups by traits. For example,
you can (mentally) combine all of the boys and consider them separate from the group
of girls. This would be a classification by a trait, leading to two different classes
(classes 1 and 2 in Figure 2.5). As a completely different method, there is a second
grouping alternative. You can unite all children into a group that holds hands with
each other and are separated from children in a second group; this is a type of
relational grouping that leads to two groups, which are both entirely different from
those in the first example given (relational groups 1 and 2 in Figure 2.5). The second
method of grouping is based on entirely different principles of affiliation; it is a
grouping according to mutual cohesion. For one particular child to belong to the
group, it is not enough that the child has any one particular trait within itself; the child
must have a (real) relationship with a second child.
The difference between class formations, as opposed to relational group formations,
also becomes clear in the following example: the term man leads to an
entirely different group affiliation than the term brother. Maleness is an intrinsic
trait that assigns every man to the male group. This group affiliation is given to every
individual man by his own account and does not require an organism of reference.
You do not need a second man or a woman to belong to the male group. However,
brotherhood is a concept that necessarily requires a person of reference, namely, a
second sibling, to meet the requirements for the term brother and to belong to the
brother group. One human being on his own can certainly be a man, but he can never
be a brother on his own. A person of reference is also necessary to be a daughter;
otherwise the concept of daughter does not make sense. In this case, the person of
reference is a mother or a father. Without a mother or a father the concept of
daughter cannot be applied meaningfully.
These considerations are of an immediate relevance to taxonomy. Each taxonomist
should be aware of the foundations for group formation because taxonomists make
or discover groups. Can an organism belong to a species if it exists by itself? Does it
inherently carry all of the criteria for a species affiliation? Does the organism need a
second organism of reference to belong to a species? The answer to these questions
depends entirely on the method of group formation that is applied by the taxonomist,
that is, either class formation or relational group formation. This example alone
makes clear how important it is to first understand the foundations of group
formation before taxonomical classifications are conducted.