Fig. 5

Stochasticity in alewife morphological evolution. A low eb value indicated that alewives’ small body size substantially improved the efficiency of their foraging for small prey. θ _P(A) was the standard deviation of the frequency of the allele improving alewives’ growth. θ _P(B) was the standard deviation of the frequency of the allele increasing alewives’ gill-raker number. The intensity of within-trophic competitions was moderate (eA=1). Trophic interaction were moderate (eI=0.4). Alewives’ small gill-raker spacing did not undermine the efficiency of their foraging for large prey (lp=0). There were three prey clusters. Allele frequencies were recorded every 150 years in this figure