Figure 3.

Eggs used in three experimental trials. Each row of images represents one egg rejection trial, with experimental eggs on the right. Also noted are the values of higher-level (NPM) pattern, low-level pattern and colour differences between experimental and host eggs. The three selected trials shown here illustrate cases where (1) NPM experimental-host distance is high but low-level differences are low; (2) low-level differences are high, but NPM experimental-host distance is low; (3) all pattern differences are low, but colour difference between experimental and host eggs is high. The experimental egg was rejected in all three of these experiments.