A true dark chocolate will never have sugar listed first in the ingredients. It should always be below the cocoa ingredients. It should also tick as many of the following points:
Antbirds are mostly birds of humid lowland rainforests. Few species are found at higher elevations, with less than 10% of species having ranges above 2000 m (6500 ft) and almost none with ranges above 3000 m (10000 ft).
This study would be comparative. Kettlewell then directly observed bird predation by placing light and dark moths on tree trunks and recorded how many times a bird found a moth. He found that birds were twice as likely to eat a dark moth on a light tree than a light moth on the same color tree, and vice versa.