The Bomb Essay, Research Paper

Symbiotic relationships have been observed amongst a vast range of organisms throughout nature. One such host-symbiont relationship that has been observed is that of sea anemones and their algal symbionts. The full extent and dynamics of these relationships, such as the factors that influence, regulate, and limit these relationships, are not fully understood. This study (LaJeunesse and Trench, 2000) compiles and analyzes the genetic profiles of dinoflagellate symbionts found in the sea anemone, Anthopleura elegantissima, gathered from populations ranging from Washington to Southern California.

Algal cells were isolated from the Anthopleura e. that were collected from sites in Washington, Oregon and California. Restriction length polymorphism (RFLP) analysis, denaturing gradient gel electrophoresis (DGGE), and DNA extraction, amplification, sequencing, and analysis techniques were performed on the algal cells. The data collected from the algal cells was used to determine the genetic profiles of the symbionts.

Analysis of the RFLP and the DGGE result, both, revealed that there was only a single species in the A elegantissima that were collected from the northern sites, while those samples which were examined from the southern populations showed the existence of at least two different species of algal cells. The results indicated that the individual species found in the northern A. elegantissima was a single symbiodinium species, which they proposed to call S. muscatinei. The data from the Southern A. elegantissima indicated that the two species were S. muscatinei and S. californium. The Data collected was used along with data from earlier studies was used to create a phylogenic reconstruction of the Symbiodinium lineage which illustrates the how the different algal species are related. The coexistence of the two Symbiodinium species in the sea anemones corresponds to earlier studies that have shown mixed populations of symbionts in some coral taxa.

It is hypothesized that certain environmental factors play a key role in determining the distribution and dynamics of the symbiotic relationships. Cold temperatures or temperature fluctuations may account for the lack of S. californium in the northern anemone populations, which are exposed, to colder temperatures and larger temperature fluctuations. This may allow for S. muscantinei to grow at a rate that allows it to out compete the S. californium in the northern climates.

The specificity of the host-symbiont relationship depends on the interplay of numerous factors. The host Cnidarians are exposed to extensive amounts of different microalgal species but they are very selective, forming symbiotic relationships with few algal species. Better understanding of the mechanisms and extent of the physical environment s influence on the dynamics of symbiotic relationships requires further experimentation