An extensive new study on baboons has uncovered a mother-infant bond that persists even in death. Over 13 years, mother chacma baboons in the Namibian desert were observed carrying their dead infants for as long as 10 days before the body was abandoned, say researchers at University College London and France's Université de Montpellier. Their findings, published in Royal Society Open Science, describes 12 cases of infant deaths, including two stillbirths and a miscarriage. Mother baboons carried the dead for between one hour and 10 days—but for three to four days on average. During this period, the mother groomed the body, while males, often the infant's father, sometimes offered protection. In other words, both maternal and paternal behavior continued, per Newsweek.
It's unlikely the mothers believe the infants are alive, as bodies are often carried by a limb, or dragged. This never happens with a live infant, even one that is sick. Rather, it's believed that, "once formed, the [mother-infant] bond is difficult to break," lead author Alecia Carter says in a release. She suggests the mothers are also "dealing emotionally with their loss." Researchers believe factors including cause of death, a mother's age, and climate conditions determine how long a dead infant is carried. While chimps and macaques have been known to carry dead infants for a month—one macaque did this long after her infant became mummified, per Live Science—chacma baboons "travel much longer distances on an average day ... making it costly for a mother to carry her infant for long periods," Carter says. (Orcas have exhibited the same behavior.)