Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
The extended parenting hypothesis. Grey box: aspects related to living in family groups. Green stippled boxes: ecological aspects; purple checkered boxes: life history aspects; blue boxes: extended parenting and social aspects; orange box: cognitive aspects; brown dashed box: costs of learning and brains; black squared boxes: links to other hypotheses.
