CHAPTER XXIIl 



THE LOCUST, A EEPRESENTATIYE OF INSECTS 

 (By Vasco M. Tanner, Brigham Young University) 



Insects are the most abundant creatures on the earth today. There 

 is said to be over 650,000 living species, many of which have never 

 been seen by the great majority of mankind. This, no doubt, is 

 because insects exist in every type of habitat known. They are 

 found in sea water along the shore; in fresh water that ranges in 

 temperature from 50° C. to ice cold; in the soil; in dry desert con- 

 ditions; on the vegetation of plain and sw^amp; from the tundra of 

 the north to the tropical pampas ; in trees ; on and in animals, as well 

 as irian, many of which are carriers of disease. They ravage our 

 crops and damage guv stored foods. In short, we may say that insects 

 are omnipresent. One noted entomologist has said that this is an age 

 of insects, and to this we may add that every man's farm is ''no man's 

 land" and that the contending forces are insects and man. 



This great class Insecta of the Phylum Arthropoda has been upon 

 the earth from the Pennsylvanian times, of the late Paleozoic era, to 

 the present. This means that for probably one hundred million 

 years these arthropods have been adjusting to a changing environ- 

 mental complex, and the success with which they have met the chal- 

 lenge is quite evident today. 



Aside from the chitinous exoskeleton, other distinctive character- 

 istics, such as power of flight, which is possessed by no other in- 

 vertebrate animal; a tracheal system, which keeps the hemolymph 

 or blood from becoming impure; and finally their great variability 

 and power to reproduce, have made the insects, no doubt, the suc- 

 cessful creatures they are today. This leads us to wonder how 

 successful man will be in his evolution during the next fifty million 

 years. Will he be able to meet the demands of a changing environ- 

 ment as the insects have? 



Insects are Arthropoda in which the body is divided into three 

 regions, the head, thorax, and abdomen. The head, whiqji consists 

 of six segments, bears a single pair of antennae, the eyes, and the 

 mouth parts; the thorax consists of three segments and is the re- 



415 



