Olive Warblers: Family Peucedramidae

The family Peucedramidae contains only one distinct species, and several sub-species of the Olive Warblers. This family has a very limited distribution, from Arizona and New Mexico to central Mexico, and is the only family of Passerines with populations only in North America. These birds were, for a long time, considered New World Warblers, because their appearance and habits were so similar, but exhibit small differences that allow them to be placed in a completely different family.

Olive Warblers are typically about 5.5-6 inches long and have a grey-black body, and bright yellow head. They differ in brightness of color and general size according to how far North and South they live. Species that live further North are generally bigger, and species that live further South are smaller. This size difference is a special adaptation that allows Northern species to conserve body heat in colder climates.

Taxonomy and Crazy Cool Evolution

Olive Warblers differ from their relatives, the New World Warblers in several ways. Their bill is more slender and round, their wings are longer, and the bristles around the eyes of Olive Warblers are smaller and weaker than New World Warblers.

Olive warblers are a member of a group of birds known as the Nine-Primaried Oscines. This group contains several families of birds, including: American Sparrows, True Finches, New World Warblers, Icterids, Cardinals, Tanagers and Hawaiian Honey Creepers. All of these families evolved in South America and radiated all across the New World. Scientists believe that Olive Warblers were one of the first families to branch off of the group containing finch-y birds, such as Sparrows, Finches, Cardinals and other Warblers. This family only contains one genus:
Genus Peucedramus