A8SO< I \T10N UN 



As.- n immediately affects selection and - 



Life in groups afford* ernes of cli- 



mate and from ferocious animal enemies. In the snow 

 storm, sheep press together and keep warm. Certain 

 animals mov<> in herds and flocks, so that in case of 

 dang* are able to stand off the enemy. The iso- 



late.l animal unahle to sustain bodily warmth in the face 



()f the I' 



to exterminate the Millie imli\ ilual. In tlii.s way it 

 happens that sociability has a definite >ur\ i\ al value, for 



up life is selected to 



survive, while the individual living an isolated existence 

 the advantage of cooperation and is more often 



" in societies insures a larger and a more certain 



food supply. Social animaN hunt in park-, wh.-n tii.-ir 

 r-ntfth is often able to vanquish prey that 



on. of them rould not overcome singlehanded. M 

 . food secured by one of the pack is often shared with 

 ther members, while an unsocial animal would be 



Hut >f association and group life upon 



is foun-l in the fact that through tin- advantages 

 lion aii<l fnml supply gaiiifl l>y cooperatioi 

 mutual ai-l. th<- a\ . rage soeia! animal has a tx-tt<-r <-) 



arh maturity ami hav.- otTsprinir. I'n-l.T the safer 

 rmiilitions of group life, more j>' can reach ma- 



than is possible in the uncertain state of isolated 

 families. In a previous chapter we saw that survival 

 meant more than rontinnance of i lividual lit' 



meant the i it ion of the race by the rearing of 



progeny. Survival in this sense means that certain ad- 

 vantageous characteristics possessed by the parents, will 



