By Richard Groover

ForIn Search of Symbiosis

EVPP 991 - Spring 2010

What is it ?Why is it important ?How has the concept evolved ?Where might we find examples in the PRV ?

Symbiosis: An ecological relationship between two organisms of two different species that live together in direct contact (Campbell et al. 1999).

Symbiont: The smaller participant in a symbiotic relationship, living in or on the host (Campbell et al. 1999).

Symbiotic relationships that result in a fusion of the entities, resulting in the formation of a new species (Roossinck 2008).

The origin of organisms through the combination or association of two or more beings that enter in symbiosis (Merzhkowsky).

Symbiogenesis is an evolutionary mechanism (Margulis 1990).

(Vellai & Vida 1999)

Konstantin Mereschkowsky (1905)

Eukaryotes formed from Prokaryotes engulfing other cells, and those cells were not internally digested … and remained as organelles in the “host” cell.

So, mitochondria and chloroplast were formed this way.

Provides sound basis for Cell Theory

Provides a basis to discover understandings on Systems Function

Provides the foundation for Endosymbiotic Theory

Lynn Margulis (2000)

1879 H.A. DeBary coined “Symbiosis”(unlike organisms living together)

1905 K.S. Mereschkovsky coined “symbiogenesis”(origin of evolutionary novelty via symbiosis)

1920’s I.E. Wallin advanced the connection with Darwinism1980 The fields of Endocytobiology was emgering

Jellyfish & fin-fish species (harvestfish & butterfly fish)

Alpheid shrimp & Xanthoid crab

Is symbiosis more of a lower organism/higher level event and less of a higher / higher level organism event …

Campbell, N.A., Reece, J.B., Mitchell, L.G. 1999. Biology, 5th edition. Benjamin/Cummings, Menlo Park, CA.

Margulis, L. 1990. Words as Battle Cries: symbiogenesis and the new field of endocytobiology. Bioscience, 40: 673 – 677.

Roossinck, M.J. 2008. Symbiosis, mutualism and symbiogenesis. Plant Virus Evolution. Springer-Verlag, Berlin

Vellai, T. and Vida, G. 1999. The origin of eukaryotes: the differences between prokaryotes and eukaryotes cells. Proceedings: Biological Sciences. 266: 1571 – 1577.

Wikipedia (photos)