Phylogenetic nomenclature ties names to clades, groups consisting of an ancestor and all its descendants. These groups can equivalently be called monophyletic. There are slightly different ways of specifying the ancestor, which are discussed below. Once the ancestor is specified, the meaning of the name is fixed: the ancestor and all organisms which are its descendants are included in the named taxon. Listing all these organisms (i.e. providing a full circumscription) requires the full phylogenetic tree to be known. In practice, there are only one or more hypotheses as to the correct tree. Different hypotheses lead to different organisms being thought to be included in the named taxon, but do not affect what organisms the name actually applies to. In this sense the name is independent of theory revision.
Read more about this topic: Phylogenetic Nomenclature
Other articles related to "definitions, definition":
... the need to have precise terminology that cannot be confused with other words or definitions ... He gave emphasis on avoidance of words that have many definitions and compared the language of Scientology with the language of Math and other precise doctrines ... place a heavy emphasis on understanding word definitions ...
... Although topographic maps of the Chile and Argentina border region which contains the highest peaks are of notoriously poor accuracy, with elevation errors exceeding 100 metres (330 ft) in many cases, the current consensus based on the most recent measurements places Ojos del Salado as the 2nd highest peak and highest volcano in South America, significantly higher than Monte Pissis. ...
... Some definitions of language, such as early versions of Charles Hockett's "design features" definition, emphasize the spoken nature of language ... would not qualify as a language under these definitions, as it is primarily a written form of communication (to see why, try reading Maxwell's equations out loud) ... However, these definitions would also disqualify sign languages, which are now recognized as languages in their own right, independent of spoken language ...
... A theoretical (or conceptual) definition gives the meaning of a word in terms of the theories of a specific discipline ... This type of definition assumes both knowledge and acceptance of the theories that it depends on ... An example of a theoretical definition is that of "Heat" in physics, which actually puts forth an entire theory of heat (involving accelerating molecules, etc.) ...
Famous quotes containing the word definitions:
“The loosening, for some people, of rigid role definitions for men and women has shown that dads can be great at calming babiesif they take the time and make the effort to learn how. Its that time and effort that not only teaches the dad how to calm the babies, but also turns him into a parent, just as the time and effort the mother puts into the babies turns her into a parent.”
—Pamela Patrick Novotny (20th century)
“Lord Byron is an exceedingly interesting person, and as such is it not to be regretted that he is a slave to the vilest and most vulgar prejudices, and as mad as the winds?
There have been many definitions of beauty in art. What is it? Beauty is what the untrained eyes consider abominable.”
—Edmond De Goncourt (18221896)
“What I do not like about our definitions of genius is that there is in them nothing of the day of judgment, nothing of resounding through eternity and nothing of the footsteps of the Almighty.”
—G.C. (Georg Christoph)