Biogeography

What is it?

 

            Biogeography is the division of Biological Sciences that studies the creatures’ existance (animals and plants) on the Earth surface (continentes and oceans and, also, the causes of this distribution in terms of space and period. 

 

Divisions

 

        Biogeograpphy is divided in:

          - ecological biogeography which studies the environmental factors that determine  orgamisns distribution;

         - Historic biogeography that based on historical factors studies the spacial and temporal distribution of creatures.

 

         Also considering the creatures division, biogeography is divided in:

-          Fitogeography: when it is related to plants distribution;

-         Zoogeography: when the animals distribution is studied.

In both there is a subdivision in:

-          Terrestrial when the terrestrial environment is studied and

-         Marine: when there is a relation to marine plants or animals. 

 

History-temporal Component

 

        As well said by Prof. Dr. Gustavo Augusto S. de Melo in his studies, from the São Paulo University Zoology Museum, biogeography can’t be resumed to the actual species distribution. There must be an historical proceed. There always must exist an historical component, because there must be an explanation on how the distribution was in the geological past, and in wich way the studied species have reached the actual distribution.

 

         For example, it is informed by the quoted professor that the marine zoogeography, in which he is specialist, that studies the animals distribution at the seas and oceans and the causes of this distribution in relation to space and time, which would be the spaces and what does it mean?

 

         Space: all of the regions that are called marine, as the beaches, continental plataform etc.

 

         Time: geological events succession, as the islands raising in Panama, at the end of Plioscene or at the beginning of Pleistoscene, closing the link between Atlantic and Pacific Oceans, separating these two faunas, that until that were only one. This separation, with the geological time (million of years), made these two faunas (Atlantic and Pacific) having  own characteristics, so they progressivily got less homogen, as one of the mainly factors that influence on the species differenciation of species, genes, families, or even faunas, is its isolation.

 

         It is also said that the above example ios just one of the countless aspects treated by Marine Zoogeography. Among these studies, we can quote: seas and oceans notions, sea’s diversity, marine fauna composition, biogeographic barriers or limits, ecology and the sea evolution, marine fauna origin, the temperature importance in relation to animals distribution.

 

         Also for Helmut Troppmair, the space component is always present.

 
       
Ecoregions

    

        In the terrestrial biogeography there is a division that adopts units called Ecoregions, for better ecossystems’ definitions and studies.

 

         Nowadays thare are 869 ecoregions that are distributed in 14 terrestrial environments around all the Globe, and in Brazil there are 78 of these areas (WWF and Ibama notes).

 

         The classification in ecoregions helps a lot in studies projects and environmental management, because it joins somer areas with similar characteristics, making easier the local fauna and flora studies.

 

Conclusion

 

So, biogeography is a very important Science that studies life on the Earth, dividing it in regions, observing space and time, being a complex Science that can imensurable contribution to global environment studies, and consequently collaborating to environmental preservation programs and projects, as also giving subsidies to the growing Environmental Law, so the reason for our unserstanding about the necessity of this page in our site.        

 

Basic Bibliography:

 

- BRIGGS,J.C. 1966. Zoogeography and evolution. Evolution,20(3): 282-289.

- BRIGGS,J.C. 1974. Marine Zoogeography. New York, McGraw Hill. 475p.

- DARLINGTON, P.J. 1957. Zoogeography: the geographical distribution of animals.New York, John Wiley (ed.). 675p.

- EKMAN, S. 1953. Zoogeography of the sea. London, Sidgwick and Jackson (ed.). 417p.

- MELO, G.A.S. 1985. Taxonomia e padrões distribucionais e ecológicos dos Brachyura (Crustacea: Decapoda) do litoral sudeste do Brasil.Instituto de Biociências Univ. São Paulo. 291p [Tese de Doutorado].

- TROPPMAIR, H. 1987. Biogeografia e Meio Ambiente. Edição própria. Rio Claro.São Paulo

- WOODRING, W.P. 1966. The Panama landbridge as a sea barrier.Proc. Amer. Phil.Soc., 110 (6): 425-433.

Sites:

   

- http://www.geocities.com/RainForest/Canopy/1464/ 

 

- http://www.biogeography.org/ 

 

- http://www.fortunecity.com/campus/biology/752/biog1.htm

 

Collaboratin in this page by Prof. Dr. Gustavo Augusto S. de Melo, From São Paulo University Zoology Museum (definition and Marine Biogeography information).

previous        Main Page          next

 

All Rights Reserved

www.aultimaarcadenoe.com