1973] 
Ramousse — A raneus diadejnatus 
43 
the two groups. Hunger is an important drive for web-building and 
prey catching, which in turn increases the amount of food available 
to the spider. As a consequence, a good supply of food permits the 
spider to use more energy to metabolize tissues and silk, and a full 
supply of silk lowers the threshold of web-building. So, the fre- 
quency of building may be controlled by a changed feed-back between 
hunger and amount of food eaten. 
A strong relationship exists between the rate of growth and the 
rate of maturation. But the number of molts was not constant, nor 
was the time separating two successive molts. The FG males went 
through fewer stages than the SG males (significant only in set I) 
and in less time. The rapid increase of the body weight of the FG 
spiders seems to force these spiders to change more often their rigid 
skins. Ecdysis is a crisis that requires extra energy to overcome; the 
heavy eating FG spiders could accumulate this extra energy in the 
form of reserves more rapidly than the SG spiders. The differential 
maturation may be attributed to nutrition. But nutrition is a func- 
tion of the amount of food eaten controlled through appetite, pro- 
ficiency in prey-catching, and web-building frequency. Similar rela- 
tions must explain the differences in development between males and 
females as well as between females of the same set. 
Different schedules of feeding result in differential growth and 
maturation for spiders of the same set (Benforado and Kistler, 
1972), suggesting that the amount of food eaten is a determinant 
factor. But with the same amount of food available, the spiders of 
the same set show different growth rates and maturation rates (Reed 
& Witt, 1972). This indicates that prenatal or genetic conditions 
control the development and maturation. In our study, the spiders 
could choose the food quantity they need through their behavior. 
When the spiders are in identical environmental conditions, we may 
assume that the difference in behavioral patterns present at hatching 
time probably are genetically determined. One pattern induces some 
spiders (FG) to capture and eat more food than other spiders, and 
in turn this large amount of food eaten by these spiders, increases 
their rate of development and maturation. The rapid growth in the 
two sets occurs at the expense of endurance and maybe weight in- 
crease, the FG males are short livers and small weighers. The short 
life-span of the FG spiders prevent them from mating with females 
of the same set, while some SG males live 'long enough to mate with 
the FG females of their own set. 
