Hartman and Oring (2003) studied the importance of nest orientation to nest microclimate in Horned Larks in California.
Nests showed a significant northern bias in orientation angle and were 49% shaded in the early afternoon, the hottest part of the day.
The dashed circle represents the outline of a nest.
Each individual curved black bar represents the vegetation around one nest.
This indicates that the even the earliest birds built nests to protect their eggs and young (From: Chiappe 2009). Cornell Lab of Ornithology, Ithaca, NY; Retrieved from the Birds of North America Online: Scharf, W.
Orientation and microclimate of Horned Lark nests -- Across their range, Horned Larks typically construct nests adjacent to & north of objects such as a tuft of grass or a rock.