Bio3520
Chapter 16
Aging and Disease
All animals
experience
after the age of
maturity:
their probability of dying increases with increasing age.
One possible genetic basis for senescence is the
pleiotropy
model, as exhibited in some fruit
flies.
Disposable
theory suggests that there in a tradeoff in balancing resources between
traits
(involved in maintenance and repair) and reproductive
traits;
sometimes this is affected by sex
ratios.
Many animals can reduce the risk of infection from
by avoiding areas that have high
parasite
levels and also avoiding parasitized
conspecifics.
Some animals may engage in self-
activities
to reduce their exposure to
parasites.
Some human diets may help prevent disease;
food
in many tropical cultures may reduce bacterial infections.