CHAPTER IV 



TROPICAL FOODS 



Preliminary Remarks — Evolution — Chemical composition — Quantity — 

 Quality — Tropical food materials — Calculation of diets — Low protein 

 dietaries — Vitamincc — Lipoids — Littic-known matters — References. 



PRELIMINARY REMARKS. 



It is not our purpose to attempt to give an account of the foods 

 found in various tropical regions, but merely to give a brief summary 

 of some of the more important facts known to us with regard to 

 tropical foods, and their effects upon man. 



The subject owes much to the labours of McCay in India, while 

 Wilson in Egypt has shown how this work can be extended to other 

 parts of the tropics. 



We will begin by tracing briefly the origins of foods as far as we 

 know them. 



EVOLUTION. 



At the present time human food is everywhere more or less cooked, and it is 

 rare for mankind anywhere to eat, even for a limited period, absolutely raw 

 materials. Dr. Campbell, in a most interesting manner, has traced the evolu- 

 tion of man's diet. He distinguishes first of all the pre-cookery epoch, during 

 which evolving and primeval man lived upon raw materials, unaltered by any 

 of the chemical and physical processes involved in cooking; secondly, the 

 cookery epoch, which may be subdivided into the pre-cibicultural and the 

 cibicultural eras. In the former, although he cooked his food, man did not 

 cultivate vegetal foods, nor did he rear animals for purposes of food. During 

 this period vegetal foods would probably be used in greater quantities than 

 before, as they are easier to obtain than hunted animals; and, also, because 

 the processes of cookery, by breaking up the cellulose, rendered them more 

 easily digestible and absorbable, and therefore more nutritious, as well as 

 more palatable. Just as we have already pointed out that certain tribes have 

 remained in the status of the Stone Age almost to the present day, so certain 

 tribes — e.g., the Bushmen of Africa, the true Veddahs of Ceylon, the Anda- 

 manese of the Bay of Bengal, and the aborigines of Australia — have remained 

 in this pre-cibicultural era. These peoples obtain their foods from all sorts of 

 animals — -e-g., worms, centipedes, flies, caterpillars ants, etc. — as well as from 

 game, while their vegetal foods are collected and stored, but they have never 

 learned to extract any chemical substance — e.g., sugar — from their vegetal 

 foods. Probably this is one of the reasons why they prize honey so highly. 

 In the cibicultural era man cultivated his vegetal foods, and reared domestic 

 animals for the purposes of animal food, and here again his vegetal feeding 

 increased in amount, as this food was the cheapest and easiest to produce. 

 Here again rose the urgent need for salt, to which we have already drawn 

 attention in the account of the migrations of negro tribes. 



The arts of cultivation and domestication became gradually dispersed over 



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