It is evident from studies of organisms in fresh-water environments 
that the difficulties in understanding the complex relationships and 
interactions among organisms are compounded by lumping species to- 
gether as plant producers, herbivores, and carnivores. There is a need 
for precise identification of each species, rare as well as abundant. 
Abundant species may account for most food production, but rare ones 
often provide essential services, such as parasite removal, to other 
species. Eliminating these services may be catastrophic. In addition, 
cryptic species may be present which, while not differing appreciably 
in morphology, have quite different behavioral, physiological and 
population characteristics in the environment. 
Consideration of the function of individual species in the environ- 
ment brings into prominence the present shortage of systematists who 
define species, suggest evolutionary relationships, and identify dis- 
tinguishing characteristics of organisms. There is great need of com- 
prehensive study of the systematic, taxonomic biology of marine or- 
ganisms involving morphological, biochemical, and behavioral dif- 
ferences among species. Such studies provide a basis for selecting 
races or strains, within a single species, with characteristics which 
render them particularly appropriate for exploitation and cultivation 
by man. Characteristics of interest are rapid growth, adaptability to 
culture conditions and resistance to disease. 
If a sea-level canal is opened across Central America, many biologi- 
cal problems of great potential consequence will emerge. A number 
of species have close relatives on opposite sides of the present land 
mass which has existed for 80 million years. These closely related 
species show different amounts of divergence. What will happen if 
the barrier is breached so that organisms can move between oceans 
through such a canal? Will changing selection pressures and com- 
petition eliminate species? Will closely related species interbreed and 
form a hybrid population or remain separate with, perhaps, accom- 
pany changes in their genetic, physiological, behavioral, and popula- 
tion characteristics? Will present populations resist invasions un- 
changed, or will serious disruptions occur, accompanied by violent 
oscillations in the composition and abundance of species ? 
Knowledge of characteristics of both successful and unsuccessful 
invading species should help us predict the effects of purposeful 
introduction or removal of species elsewhere. Some changes are 
likely to be dramatic and easily documented; others will be more 
subtle although of equal importance in furthering our understanding. 
It will be impossible to recognize and understand these subtle changes 
unless the present state of populations of various species is known 
thoroughly. In view of the immediate need for background infor- 
mation, the Panel recommends undertaking an intensive study of 
marine organisms on both sides of the proposed canal site. Concur- 
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