chapter 2 



THE GENERAL LIFE HISTORY OF THE TADPOLES 



In the Amphibia, as well as in other groups of animals, it often seems 

 that the larvae receive less attention than the adults. This is curious, 

 not only because larvae have a considerable interest in themselves, but 

 because, in the study of the whole hfe history of an animal, it is often 

 the larval stage that throws much light on features of the ecology that 

 would otherwise remain incomprehensible. 



In attempting to review the hterature (Savage, 1952), I found nothing 

 on the tadpoles of R. temporaria beyond the elementary facts contained 

 in natural history books, and not much on other species except brief 

 notes which, although interesting, made no attempt to cover more 

 than some isolated phase of the life. All the references on tadpoles for 

 this and later chapters are therefore of this rather minor character. 

 Here, the tadpoles are treated not as temporary animals in the process 

 of becoming something else, but as animals whose life, although short 

 compared with that of the adults, is hved on an entirely different plane, 

 and has called for special larval organs, habits and responses, to be 

 considered just as if the adult frog had never been discovered. 



In the last chapter, the narrative continued until the stage at which 

 the tadpoles began to feed. Their behaviour after this time differs in 

 different ponds and on different occasions. An adequate picture of the 

 instability of hfe in a pond, and of the ups and downs of tadpole life, 

 cannot be gained by compressing the events into one colourless 

 summary. The risks, the successes, the disasters overtaldng whole 

 populations are fundamental to the ecology of the animal, and for 

 their understanding detailed descriptions of specific instances are 

 essential. 



The methods adopted for the investigation were very simple. As 

 many ponds as could be studied in the time available were visited at 

 approximately weekly intervals, the tadpoles observed at hberty, and 

 a sample collected and preserved for future study. Each tadpole was 

 then weighed, some were dissected and the contents of the gut examined 

 microscopically. The variety of events in tadpole ponds is so great 

 that I hesitate to pick on one and label it as *'normal," but it has seemed 



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