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dredged from the ridge on the floor of the middle Atlantic Ocean indicate that 

 enlightening information on the structure and movement of the Earth's crust 

 could be gathered by deep diving vehicles. With chartered underseas vehicles, 

 the Smithsonian plans to make detailed studies of this poorly studied but promis- 

 ing geological area. 



Tvpo program areas of particular interest would employ research submersibles 

 with lock-out capabilities. With the development of saturation diving techniques 

 and submarines which may be equalized to ambient pressure in the shallow 

 ocean, it has become possible for scientists to work exposed to the ocean environ- 

 ment for extended periods at depths up to at least 150 meters. Man himself is 

 the most versatile scientific tool, and this ability to work in the hostile oceanic 

 milieu is an important step forward in the efforts to explore and to understand 

 the sea. 



The first program area involving lock-out vehicles combines detailed obser- 

 vations of the distribution and abundance of the ocean biota with in situ experi- 

 ments. Work has been performed in evaluating the influence of light on animal 

 behavior and new observations have been made on the mating of cephalopods 

 in a natural environment. The experimental work must be extended to examiiie 

 various frequencies and intensities of light and also into other areas of research. 

 Our knowledge of oceanic animals is sufficiently sparse so that practically any 

 observation that, is made represents a significant extension of data. 



As a second program the use of lock-out vehicles provides a major tool for 

 extending archeological knowledge. The recent field of submarine archeology 

 has already provided new insight into the past. With the use of submersibles, 

 submarine archeological research will be greatly facilitated. 



Another area of prime interest to the Smithsonian Institution is the Eastern 

 Pacific and the Caribbean on either side of the Isthmus. Under the auspices of 

 the Atlantic-Pacific Interoceanic Canal Study Commission, studies are presently 

 underway to determine the engineering feasibility of a trans-isthmian sea level 

 canal. Such a canal, connecting the oceans across the Isthmus, would provide a 

 unique opportunity for scientific study of the ecology of the region and any de- 

 tectable changes thereto which may accompany this project. 



Well aware of the long time between the construction of the access canal from 

 the ocean to the Great Lakes and the appearance of the sealamprey and the 

 marine alewife fish as pests in the Great Lakes, the Smithsonian Institution has 

 been concerned for several years that adequate baseline ecological investigations 

 be undertaken before construction of any sea level canal. Scientists at the Smith- 

 sonian Tropical Research Institute have already discovered that certain related 

 species of fishes from the Atlantic and Pacific Oceans can be hybridized in the 

 laboratory. 



Extrapolating from the observed morphological diversity, we can expect that, 

 after the sea level canal is completed and the barrier to dispersal is removed, 

 a wide range of changes may occur. The influx of new organisms might upset 

 the balance of some populations of marine organisms. Instances of hybridization 

 and intergradation can be predicted among those related groups from opposite 

 sides of the Isthmus which have not accumulated sufficient genetic or behavioral 

 isolating mechanisms. In some circumstances competition between newly mixed 

 elements of the biota may cause rapid changes in population densities. Some 

 species may become more abundant, while others may become extinct. New 

 species interrelationships could occur. The possible effect on harvestable marine 

 species is uncertain. 



As established during the Smithsonian Conference on Tropical Biology held 

 in Panama City, November 10-12, 196^, our knowledge of tropical marine biology 

 lags far behind parallel information in the temperate regions. Accumulation 

 of data for tropical regions is essential for the development of rational pro- 

 grams to harvest the sea and to utilize its resources. The major areas of protein 

 deficiency for human populations are in the tropics. Detailed knowledge of the 

 potential fisheries resources is but one of the side benefits to be anticipated from 

 the proposed Isthmian program. 



The Institution will utilize its existing shore facilities in the tropics to main- 

 tain adequate local research support. As necessary, it will assist in the opera- 

 tion of ships. 



Another Smithsonian activity aimed at resolving National oceanography prob- 

 lems is concerned with the processing of marine specimens. We have established 

 in Washington, D.C., the Smithsonian Oceanographic Sorting Center, and this 



