Take note: they belong to a vegetarian species.
Tonkean macaques are a species endemic to Southeast Asia. But facing a threat today on habitat loss, some of them are taken care of in animal sanctuaries.
Infant death is common among first-time Tonkean macaque moms. At the Parco Faunistico di Piano dell’Abatino animal sanctuary alone, 16 babies of 51 total births died or were stillborn. What's interesting is that the mothers were seen carrying around their infants' corpses for days! Scientists explained that this may either be a manifestation of grief or it's just that they don't know yet that the offspring is dead.
One new mother, however, baffled the researchers as she was spotted eating the remains of her deceased baby! A mother's love gone wrong?
Evalyne seemed to be really disturbed and restless after her four-day-old baby died. She was seen staring and screaming at her own reflection--a first, says lead researcher Arianna De Marco, an evolutionary biologist at Fondazione Ethoikos in Italy. Later on, she was then seen, as expected, caring for her dead infant for the first weeks.
The infant's body had actually fully mummified and later on had its head fall off. But the loving mother still continued grooming, licking, and carrying it. “I was both curious and moved at the same time,” De Marco says.
And in the third week, the unexpected happened: as soon as the rest of the remains fell apart, Evalyne started nibbling on its body. She continued consuming it until nothing but a single bone was left!
“This kind of behavior has been documented in chimpanzees and a few other primates, with mothers carrying their dead infant until it disintegrates,” notes Frans de Waal, a primatologist at Emory University. But "the new part here is the cannibalism,” he added. “Macaques do not normally eat each other.”
Not only that, “they are [actually] a vegetarian species and never eat meat," adds De Marco. “It is difficult to give an explanation for this behavior. The dramatic change of maternal behavior from caretaking to cannibalistic attitude is astonishing," he explained.
De Marco noted that this could also be explained by her newness to motherhood and that her baby lived long enough to form a mother-child bond. Perhaps Evalyne resorted to eating the infant to express her attachment.
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