True increasing evolvability in the evolved robots model with limited capacity niches.

<p>The evolvability of organisms is shown averaged over 50 independent simulations that lasted 250 generations each. It is important to note that because the population size in the limited-niche model is much smaller, <i>one</i> generation of the passive model encompasses more individuals (2,000,000) than is considered over <i>all</i> generations in the niched model ( on average). In other words, the limited-niche model is more directedly and more efficiently biased towards evolvability. In particular, the difference in evolvability between the limited-niche model and the passive model is significant for all comparisons after the 50th generation (; Student's t-test).