Maggiore efficienza di una specie rara, nella competizione interspecifica

Elisa Anna Fano

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti (1977)

  • Volume: 62, Issue: 5, page 685-691
  • ISSN: 0392-7881

Abstract

top
Since 1969 systematic sampling has recorded the appearance in nature of a species, Asellus (Proasellus) coxalis Dollf., and its progressive increase in a biotope (Sarno River, Naples) previously occupied by the single species Asellus (Asellus) aquaticus (L). The two species are at present living in sympatry. It has been noted that both species undergo significant numerical variations in the various months of the year. The maximum peaks for coxalis fall in the two month period April-May and for aquaticus in the two months December-January. Laboratory experiments have confirmed the hypothesis of Haldane (1932), according to whom a rare species is at an advantage in interspecific competition and tends towards a progressive increase. They also confirm the hypothesis of Ayala (1971) who claims that there are divergencies of characteristics in two competing species forced to live in sympatry. Mixed breeding for the study of interspecific competition between the two species, which do not hybridize, was possible thanks to the finding of a distinctive morphological characteristic, the different distribution of «Zenker Cells», which made it possible to identify the two species in vivo, right from the extramarsupial stage.

How to cite

top

Anna Fano, Elisa. "Maggiore efficienza di una specie rara, nella competizione interspecifica." Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti 62.5 (1977): 685-691. <http://eudml.org/doc/290207>.

@article{AnnaFano1977,
author = {Anna Fano, Elisa},
journal = {Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti},
language = {ita},
month = {5},
number = {5},
pages = {685-691},
publisher = {Accademia Nazionale dei Lincei},
title = {Maggiore efficienza di una specie rara, nella competizione interspecifica},
url = {http://eudml.org/doc/290207},
volume = {62},
year = {1977},
}

TY - JOUR
AU - Anna Fano, Elisa
TI - Maggiore efficienza di una specie rara, nella competizione interspecifica
JO - Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti
DA - 1977/5//
PB - Accademia Nazionale dei Lincei
VL - 62
IS - 5
SP - 685
EP - 691
LA - ita
UR - http://eudml.org/doc/290207
ER -

References

top
  1. HALDANE, J. B. S. (1932) - The Causes of Evolution. New York, London and Toronto: Longmans, Green and Co.. 
  2. AYALA, F. (1971) - Competitioìi between species: Frequency depedence, «Science», 171, 820-823. 
  3. FANO, E. A., ROSSI, L. e VITAGLIANO TADINI, G. (1974) - Ricerche sui rapporti fra due specie del genere Asellus. Nota I. Competizione. «Rend. Acc. Naz. Lincei», ser. VIII, 56(6), 1-8. 
  4. BALESDENT MARQUET, M. L. (1963) - Répartition des cellules de Zenker et détêrmination spécifique de Asellus (Asellus) aquaticus (L.) sensu Racoviiza et Asellus (Proasellus) meridianus Rac., «C. R. Acad. Sc.», 256, 262-264. 
  5. ZENKER, (1854) - Citato da Balesdent Marquet, 1963. 
  6. FANO, E. A., ROSSI, L. e VITAGLIANO TADINI, G. (1977) - Divergenza fra due specie attualmente simpatriche: Asellus aquaticus (L.) e Asellus coxalis Dollf. (in corso di stampa). 

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

                
Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.