Monday, April 16, 2012

The infamous "Tots" pulling a seine 

You do not need to be a fish fanatic to be humbled by the diversity of extant fishes observed worldwide. With incursion into nearly all available habitats, including terrestrial, fishes have dominated the vertebrate world in terms of both abundance and diversity. As we ventured through the currently accepted phylogenetic tree of fishes, it was noted that the breadth of extant species occur in the infraclass Teleostei. To delve into the mechanisms of niche expansion and the genetic arsenal required to make these life history transitions goes beyond the scope of the class, however Dr. Heppell summarized this information by outlining the general change in both form and function in species throughout evolutionary time.  Once the lectures were over, the class conducted dissections of multiple fish species- Black Rockfish (Sebastes melanops), Blue Rockfish (Sebastes mystinis), Kelp Greenling (Hexagrammos decagrammus)- within the order Scorpaeniformes. Looked at during the dissections were the general internal anatomy of fishes: gonads, kidneys, spleen, liver, otiliths, etc.  Lastly, we had the opportunity to engage in a survey of near shore fishes of Yaquina Bay, OR. This was a phenomenal way to end the day because the class gained experience in beach seining techniques, as well as general species identification methods.      

Alicia Haynes holding a juvenile
Staghorn Sculpin (Leptocottus armatus)

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