238 THE HAUNTS OF LIFE 
respiration, which would raise the pitch of 
the insect’s life. 
WHY ARE THERE SO MANY INSECTS? 
Many naturalists estimate the number of 
different kinds of living backboned animals 
named and known at about 25,000. But of 
named and known backboneless animals there 
are ten times as many, and the most of these 
are insects! But some authorities on insects 
insist that this computation is far too mod- 
erate. They point out that, on the average, 
6000 new insects are discovered every year, 
and insist that the total number of different 
kinds now living on the earth must be put at 
over 2,000,000. As one of the experts says: 
“One fact remains certain—namely, that the 
number of species of insects is at least six 
times that of all the other animals put to- 
gether.” And besides the prodigious number 
of different kinds of insects, there is the 
colossal number of individuals that often rep- 
resent a particular species at one time. Why 
are there so many insects? 
The first part of the answer is that most 
insects have the power of true flight, which 
