Cyclical nursing patterns in wild orangutans

Tanya M. Smith, Christine Austin, Katherine Hinde, Erin R. Vogel, Manish Arora

Research output: Contribution to journalArticle

14 Scopus citations

Abstract

Nursing behavior is notoriously difficult to study in arboreal primates, particularly when offspring suckle inconspicuously in nests. Orangutans have the most prolonged nursing period of any mammal, with the cessation of suckling (weaning) estimated to occur at 6 to 8 years of age in the wild. Milk consumption is hypothesized to be relatively constant over this period, but direct evidence is limited. We previously demonstrated that trace element analysis of bioavailable elements from milk, such as barium, provides accurate estimates of early-life diet transitions and developmental stress when coupled with growth lines in the teeth of humans and nonhuman primates. We provide the first detailed nursing histories of wild, unprovisioned orangutans (Pongo abelii and Pongo pygmaeus) using chemical and histological analyses. Laser ablation inductively coupled plasma mass spectrometry was used to determine barium distributions across the teeth of four wild-shot individuals aged from postnatal biological rhythms. Barium levels rose during the first year of life in all individuals and began to decline shortly after, consistent with behavioral observations of intensive nursing followed by solid food supplementation. Subsequent barium levels show large sustained fluctuations on an approximately annual basis. These patterns appear to be due to cycles of varying milk consumption, continuing until death in an 8.8-year-old Sumatran individual. A female Bornean orangutan ceased suckling at 8.1 years of age. These individuals exceed the maximumweaning age reported for any nonhuman primate. Orangutan nursing may reflect cycles of infant demand that relate to fluctuating resource availability.

Original languageEnglish (US)
Article numbere1601517
JournalScience Advances
Volume3
Issue number5
DOIs
StatePublished - May 2017

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Cyclical nursing patterns in wild orangutans'. Together they form a unique fingerprint.

  • Cite this

    Smith, T. M., Austin, C., Hinde, K., Vogel, E. R., & Arora, M. (2017). Cyclical nursing patterns in wild orangutans. Science Advances, 3(5), [e1601517]. https://doi.org/10.1126/sciadv.1601517