Paraphilia (from ancient Greek παρά - alongside and φυλή - fila ) is the concept of taxonomy applicable to such classification systems in which the main criterion for grouping classified objects into taxa is the degree of their relationship , i.e. proximity to a common ancestor. In this case, paraphyletic groups are called groups that include only a fraction of the descendants of a common ancestor. A more formal definition reads as follows: a paraphyletic group is obtained from a monophyletic by removing one or several terminal groups from the composition of the latter [1] . This group includes its common ancestor, but not all of its descendants belong to it.
Content
The problem of the status of paraphyletic groups
The concept of paraphilia arose within the framework of phylogenetic systematics as a result of a logical analysis of the concept of monophilia and was introduced into scientific use by V. Hennig . The different approach to the status of paraphyletic groups predetermined significant differences in the views of the two most important areas of modern taxonomy - evolutionary taxonomy and cladistics .
The approach of supporters of evolutionary taxonomy to the problem of paraphilia is not significantly different from the approach characteristic of traditional taxonomy: they interpret paraphilia as one of the types of monophilia, and therefore consider it possible to save paraphyletic taxa in the system.
Proponents of cladistics, however, firmly oppose paraphilia and monophilia in the narrow sense of the word, considering only a monophyletic group that owns both the common ancestor and all descendants of this ancestor [2] . Only such groups can act as taxons in their systems, and paraphyletic groups, in their opinion, do not (as well as polyphyletic groups) have the right to exist in the system. If it is necessary to refer (during any discussion) to a paraphyletic group, many cladistic supporters write its name in quotes (thereby indicating that it is not valid).
Paraphyletic group, as a rule, cannot be characterized by unique synapomorphies . All common properties that can be specified for its representatives belong to simplesiomorphies (inherited from more distant ancestors than the closest common ancestor of the representatives of the group) or homoplasias (originated from different representatives of the studied group independently).
Examples of paraphyletic groups
Typical examples of well-known paraphyletic groups in biological systematics : primary insects , invertebrates , fish , reptiles , and artiodactyls [4] [5] [6] . In cladistic systematics, they either subdivide these groups into smaller groups (already monophyletic), or, on the contrary, expand their volume due to the inclusion of specialized groups that have not previously been related to them.
The same problem of differentiation of mono-and paraphyletic groups arises in linguistic taxonomy (an additional argument of supporters of the use of paraphyletic groups in linguistic classifications is the fact that in a number of linguistic families and groups the processes of linguistic divergence are quite fully reflected in written monuments, so often the origin is not purely hypothetical, but quite real language education). Thus, VN Toporov , expressing a rather traditional view of the composition of the Indo-European family , singled out 17 groups in it [7] (some of which are monotypic taxa represented in the same language). Among these taxa, the Italic and Romance languages have the same group rank; Meanwhile, it is known that the Latin language serves as the proto-language for Romance languages (more precisely: the Proto-Romanian coincides [8] with the so-called Vulgar Latin - the sister of classical Latin, whose common ancestor - Latin Gracchus - belongs to the second half of the 2nd century to. Mr. e.).
See also
- Kladistika
- Evolutionary taxonomy
- Monophilia
- Polyphilia
- Paragroup
Notes
- ↑ Shatalkin, 1988 , p. 178.
- ↑ Shatalkin, 1988 , p. 35
- ↑ Laurin, Michel; Gauthier, Jacques A. Amniota . Tree of Life Web Project (1996). The appeal date is January 25, 2010. Archived on February 3, 2012.
- ↑ Colin Tudge. The Variety of Life. - Oxford University Press, 2000. - ISBN 0-19-860426-2 .
- ↑ Romer AS , Parsons TS The Vertebrate Body. 6th ed. - Philadelphia: Saunders, 1985.
- ' O'Leary MA : “Combine Data Analysis”, “ American Zoologist” , 41 (3), 2001. — P. 487–506. - DOI : 10.1093 / icb / 41.3.487 .
- ↑ Toporov VN Indo-European Languages // Linguistic Encyclopedic Dictionary. - M .: Owls. Encyclopedia, 1990. - 685 p. - ISBN 5-85270-031-2 . - p. 186-189.
- ↑ Comparative historical study of languages of different families. Tasks and prospects. - M .: Science, 1982. - 343 p. - p. 129.
Literature
- Shatalkin A. I. Biological systematics . - M .: Publishing House of Moscow. University, 1988. - 184 p. - ISBN 5-211-00145-1 .