GROWTH AND THE AGING PROCESS 



955 



•"EAR 



65-- 

 60-- 

 55 -|- 

 50 

 45 



- 40 



O 35 



i 30^ 

 <I 



IT 



3 25 4 

 o 



20 

 154 

 I0-- 

 5 -■ 



o MAN 



O CATTLE 



® SWINE 



« SHEEP 



D FOWL 



a RABBIT 



• 6UINEA PiG AND CUTlERi 



A RAT (ALBINOl 



■ MOUSE 



K PIGEON AND DOVE 



NORWAY RAT 



Fig. 3. Diagram showing that in a num- 

 ber of animal species the duration of life 

 is directly proportional to the length of 

 time to reach mature size and therefore 

 inversely proportional to the speed of 

 maturation (value of K). 

 (Redrawn after Brody, 1945). 



.3 .4 .5 ,6 

 VALUE OF K 



20 30 40 50 60 

 AGE 



I 234 56789 10 



Fig. 4 



Fig. 5 



Fig. 4. Curve to show the rapid decline in power of accommodation of the eye at age 10 



years. This phenomenon tends to substantiate Minot's view that the rate of aging is greatest 



in earliest years. While the lens continues to grow, it is at a declining rate, thus bringing 



about a decrease in the amount of young tissues with increasing age. 



(Redrawn after Brody, 1945). 



Fig. 5. Typical growth curve of a fish, Clupea harengus. The long continuation of growth is 

 paralleled, too, by increasing egg production. (Redrawn after Bourliere, 1953). 



Literature p. gyi 



