Principios de Taxonomia

54j 3 Is the Biological Species a Class or is it an Individual?
physically annihilated, they could regenerate. The class of football teams certainly
has defining properties; the number of individual elements (always eleven), the
footwear and other clothing, the objective of the game (to score goals) and so on. A
team that consists of twenty players and pursues a different aim than making
goals would be an element that does not belong to the class of football teams, but
the group of eleven players on an individual football team is an individual, not a
class. Manchester United cannot be defined.
For example, if one needed to define the Great Tits (Parus major) by their physical
properties, they would just describe an individual by its properties. The Great Tits
have black head plates, yellow bellies, perform a particular song, and so on, but
this is not a definition of Great Tits; instead, something that has an individual
existence is described, not defined.
The only plausible way to consider a terrestrial Great Tit as an element of the class
of Great Tits would be if there were other groups of Great Tits on other planets that
shared Great Tit properties. However, the theory of descent implies that the discovery
of a bird on a distant planet that shares all of the properties of a Great Tit must be
interpreted as a migration of Great Tits from the Earth to another planet or in turn
from the distant planet to the Earth. However, then these distant Great Tits would not
be elements of a class but rather parts of one single individual. Otherwise, these
apparent Great Tits on the distant planet would not be Great Tits but would instead be
the result of an independent convergent evolution. Considering these animals to be
Great Tits would be an incorrect view that ignores the biological rule of descent.
Hence, the fact that biological species are individuals, not classes, directly follows
from the theory of evolution.
Repeatedly, there have cases in which an animal species that has already been
registered to be extinct is then later rediscovered, usually in remote places rarely
visited by humans. Of course, we all assume that the newly discovered remaining
members of the species had a relational connection to the extinct population.
Therefore, they are a part of a whole that was once been widespread. No one would
nurture the hope of rediscovering an extinct animal or plant species as a de novo
existence. Classes, however, cannot become extinct because they are universals.
3.5
Artificial Classes and Natural Kinds
A class is a group of objects with coincident traits. This leads to the problem,
depending on the selection of traits, of every imaginable aggregation of objects into
classes is possible. It only depends on a human s decision regarding which traits he
would like to use for group formation. Imagine one hundred objects that each has one
hundred traits, resulting in a large number of possibilities for combining all or some
of these objects into classes. All of these possible class formations cannot be realistic
classes that exist in nature. Some of these classes would have to be pure nonsense.
Which selection of traits leads to a meaningful or even correct class formation?