5 March 2007

Qualifying round of FAME LAB, organized by the British Council in Greece
(more info: http://www.britishcouncil.org/greece-science-beautiful-science-famelab.htm)

Fame Lab is a national talent competition to find the best new talent in science communication.

Position: 3rd runner - up FAME LAB finalist

My presentation, written (& in English!):

Nowadays, we all speak about genetically modified organisms; they are the live organisms which were created artificially with the abstraction or with the addition of genes that emanates from organisms that can belong even in completely different species. Genetically modified is a gene that has undergone mutation. Mutation is the process of modification of constitution of a cell. We say no to genetically modified organisms and yes to biodiversity, which means yes to the variety of life.

To the list of negative factors that affect marine biodiversity, we must add ‘‘genetic pollution’’. By this we mean alteration of the natural genetic architecture and microevolutionary processes of wild populations due to the gene flow from farmed conspecifics that have escaped from aquaculture plants (see: Cognetti et al., 2006). Aquaculture escapes might constitute a potential risk to the genetic integrity of wild populations of the species (see: De Innocentiis et al., 2004).

The native species sea bream Sparus auratus and sea bass Dicentrarchus labrax are the principal species of marine aquaculture in the Mediterranean.

Farming generates rapid genetic change, as a result of both intentional and unintentional selection in culture that alters important fitness-related traits. Unlike nature, culture facilities provide predator-free, high-density, rapid growth environments that can affect the morphological, behavioural, and life-historical development of the fish. Finally, the human-engineered breeding patterns and the culture environment imposed on the fish create intentional and unintentional selection that can result in domestication over a few generations. Unlike the sea-ranched fish, the farmed fish are cultured throughout their lives and never exposed to natural selection for swimming performance. Additionally, they have been subjected to directed artificial selection for rapid growth based on body weight (see: Fleming & Einum, 1997).

Wild populations, generally, are at risk from interactions with aquaculture fish that have been subject to domestication (Youngson et al., 2001).

In any case however the fishes emanate from mariculturist stations. There big fish are carefully chosen to spawn million of juveniles. Finally, juveniles are lead to cages to the marine environment. There, either because of physical conditions (bad weather, high waves etc.) or because people that are against farms tear up the nets, fish escape.

The greater the genetic difference, the greater the likelihood that releases will alter the genetic diversity or genetic composition of the natural population.

Info:

-Castilho R. & Y. Ciftci, 2005. Genetic differentiation between close eastern Mediterranean Dicentrarchus labrax (L.) populations. Journal of Fish Biology; 67: 1746–1752.
-Cognetti G., Maltagliati F., & M. Saroglia, 2006. Editorial: The risk of ‘‘genetic pollution’’ in Mediterranean fish populations related to aquaculture activities. Marine Pollution Bulletin; 52: 1321–1323.
-De Innocentiis S., Lesti A., Livi S., Rossi A. – R., Crosetti D. & L. Sola, 2004. Microsatellite markers reveal population structure in gilthead sea bream Sparus auratus from the Atlantic Ocean and Mediterranean Sea. Fisheries Science; 70: 852–859.
-Fleming I. A. & S. Einum, 1997. Experimental tests of genetic divergence of farmed from wild Atlantic salmon due to domestication. ICES Journal of Marine Science, 54: 1051-1063.
-Youngson A. F., Dosdat A., Saroglia M. & W. C. Jordan, 2001. Genetic interactions between marine finfish species in European aquaculture and wild conspecifies. Journal of Applied Ichthyology; 17: 153-162.