The name Icteridae derives directly from the Greek word for jaundice, reflecting the striking yellow plumage found on the majority of these New World birds. Irish zoologist Nicholas Vigors first formalized the group as a subfamily in 1825, placing them within the starling family before later taxonomic revisions separated them.
Among all passerine birds, the icterids exhibit the most extreme sexual dimorphism in terms of body size, with the male great-tailed grackle being 60% heavier than the female. The male Amazonian oropendola can reach lengths of 50 centimeters and weigh up to 400 grams, while the female orchard oriole averages just 15 centimeters in length and weighs a mere 15 grams.
A unique morphological adaptation shared by the icterids is the ability to gap, a specialized skull configuration that allows them to open their bills with immense force rather than passively. This adaptation enables them to force open gaps in fruit skins to access soft insides, a technique used by oropendolas and caciques to feed on tough tropical fruits.
The Jamaican blackbird, the yellow-shouldered blackbird, and the St Lucia oriole are all insular forms that face imminent danger from the destruction of their native habitats. The tricolored blackbird of California is also threatened, with populations declining due to the loss of grasslands and the destruction of nests by agricultural activities.
In Peru, the cacique and oropendola species are known as paucar, and local folklore attributes to them a level of intelligence that has influenced human behavior for generations. Native Americans in the region feed the brains of these birds to their children in the belief that it will make them fast learners, a practice rooted in the observation that the male paucar plays no part in nesting or care of the young.
A study published in 2019 by Carl Oliveros and collaborators found that the family Icteridae is sister to the family Icteriidae, which contains the yellow-breasted chat, and together these two families form a clade that is sister to the New World warbler family Parulidae. This discovery has reshaped the understanding of the family's evolutionary history, placing them in a new context within the passerine order.