The pelvis performs two major functions for terrestrial mammals. It provides somewhat rigid
support for muscles engaged in locomotion and, for females, it serves as the birth canal. The …

Highlights► Elo-rating generates reliable dominance hierarchies and circumvents
drawbacks of established ranking methods.► It allows visualizing dominance relationships …

Long-term studies of well-identified individuals and improved methodologies have
advanced primate behavioral ecology, genetics, and physiology (Kappeler & Watts, 2012; …

Human fetuses at term are large relative to the dimensions of the maternal birth canal,
implying that their birth can be associated with difficulties. The tight passage through the …

Premature loss of offspring decreases direct fitness of parents. In gregarious mammals, both
ecological and social variables impact offspring survival and may interact with each other in …

A large brain combined with an upright posture in humans has resulted in a high
cephalopelvic proportion and frequently obstructed labor. Fischer and Mitteroecker [B …

Most primates, including humans, give birth during the inactive phase of the daily cycle.
Practical constraints therefore limit our knowledge of the precise timing of nocturnal birth in …

The birth process is an integral part of reproductive success in mammals, yet detailed,
quantitative descriptions of parturition in nonhuman primates are still rare. Observations of …

Social bonds between group members affect individual fitness and wellbeing. While the
impact of bond strength is well studied, the consequences of bond predictability and …

Parturition is one of the most important yet least observed events in studies of primate life
history and reproduction. Here, I report the first documented observation of a bonobo (Pan …