DISCUSSION 63 



articles on these subjects have usually dealt only with some special point 

 of interest — or a courtesy reference has appeared in a botanical, nutri- 

 tional, or public health journal. The present assemblage of data brings 

 into focus much diversified material, a good portion of which deserves 

 closer integration into the field of medicine. 



Interest in algae and plankton has varied over the years. From ancient 

 times, the predominant emphasis was on the seaweeds ; at the turn of this 

 century, it shifted to zooplankton ; and, since World War II, it has centered 

 chiefly about phytoplankton. The traditional medicinal use of seaweed 

 has declined sharply, as has its role as a human nutrient. Its value today 

 resides primarily in the contained minerals and vitamins, and its greatest 

 utility is as fertilizer and animal provender. There is also much merit in 

 the alginates, and a good potential exists for other seaweed derivatives 

 such as the antibiotics and anticoagulants. Consideration of plankton has 

 for the most part been focused on its use as food. 307 - 309 Zooplankton is 

 nutritionally far richer than seaweed, but it does not possess the signifi- 

 cance its more enthusiastic proponents confer upon it. Despite the fact that 

 the Thais 21 have reportedly collected 5,000 tons in one year, it should not 

 be forgotten that there are tremendous variations in quantity and quality 

 of yield in different oceans and at different seasons. While zooplankton 

 may be considered an excellent emergency ration and food supplement, its 

 extensive use as a food staple awaits the development of far more efficient 

 collection techniques. 



Since it is still much too early to envision extensive in vitro photo- 

 synthesis 197 without the intermediary of plants, it is the phytoplanktonic 

 organisms which offer the most exciting prospect for nutritional gain. 

 They not only supply controllable proportions of protein, fat, vitamins, 

 minerals, and calories — they can also be cultured selectively on a large- 

 scale basis. The marvelous adaptability of algae like Chlorella gives man 

 another round in the crucial Malthusian battle of population versus food 

 supply. In the past three centuries, the world population has risen from 

 a half billion to two and one-half billion. 25 If fission and fusion do not 

 permanently put an end to both mankind and its problems, the population 

 will be four billion in 1980, and eight billion in 2050. Selective fresh- 

 water mass culture of organisms (we suggest the term "aquaculture" as 

 more descriptive than "hydroponics" and less restrictive than "mari- 

 culture" 29 ) like Chlorella in specially built plants hold great promise for 

 large quantities of valuable foodstuffs. It is more practical than "manuring" 

 the sea with salts and minerals — "three-dimensional farming" — to increase 



