1. Evolution of senescence: Alzheimer's disease and evolution
Brian Charlesworth 
Current Biology 
Volume 6, Issue 1, Pages (January 1996)
DOI: /S (02)

2. Figure 1
The sensitivity of net fitness to changes in survival (red line) or fecundity (blue line) at specific ages, as a function of age (in years). Sensitivities are measured as the partial derivatives of net fitness with respect to changes in survival or fecundity at the ages indicated. The data are for females in the Taiwan population of 1906 [9].
Current Biology 1996 6, 20-22DOI: ( /S (02) )

3. Figure 2
Antagonistic effects of a polymorphic locus with two alleles (A1 and A2) on an early (E) and a late (L) life-history trait. The relative net fitnesses of the three genotypes are also shown (F). The homozygote A1A1 has a reduced value of the late trait, relative to the maximal value, but only a moderately reduced fitness, because of the low sensitivity of fitness to changes late in life. The homozygote A2A2 has a reduced value of the early trait, and a much lower fitness than A1A1. The deleterious effects of both alleles are partially recessive, so that the heterozygote A1A2 has the highest fitness. This model results in the maintenance of variation by selection [13], with the allele which affects the late part of the life-history (A1) being present at a higher frequency than the allele affecting the late part of the life-history (A2).
Current Biology 1996 6, 20-22DOI: ( /S (02) )