In the wild, monkeys typically give birth at night when they're safest from predators. Because of that nighttime labor, researchers don't often get a chance to witness the deliveries and they have always assumed the mothers have labored alone, reports the BBC.
But researchers recently were able to watch a wild golden snub-nosed monkey (Rhinopithecus roxellana) give birth during the day. And they were surprised to see that she had help — a monkey "midwife" was there to assist her.
The helper began grooming the pregnant monkey when she first became agitated as labor started. She stayed nearby during contractions and tried several times to help the mother pull out the baby. The midwife also assisted the mother after the delivery.
The birth lasted just four minutes and 10 seconds. Immediately after she gave birth, the mother cut the umbilical cord, ate the placenta, and cleaned her new baby. The helper was permitted to hold and lick the newborn after the mother had fed and licked it first.
The researchers described their observation of the birth in the journal Primates. "Although 'aunting' or infant caregiving behavior has previously been reported in coloblines [a diverse group of primates], this is the first putative case of birth assistance in a nonhuman primate," the researchers wrote.
Golden snub-nosed monkeys are an endangered species found only in China in the wild.
The BBC points out that this isn't the first case of a monkey getting assistance during birth. In 2014, scientists witnessed a langur monkey acting as a midwife. A year earlier, a black and white snub-nosed monkey also received help during delivery.
The team is planning to record nighttime births to see if monkey midwifery is more common that previously thought.