Spider babies eating milk on bellies of spider mothers | REUTERS
Chinese scientists discovered a spider species that feeds their babies with milk as mammals, marking the first time humans discovering invertebrates breastfeeding and nursing theirs offspring, said Chinese Academy of Sciences Friday.
Breastfeeding is a unique animal behavior to mammals, including humans. This type of spider, commonly known as big ant spider, discovered with “breastfeeding behavior”, belongs to Myrmarachne of Salticidae, which is a spider species widely distributed in the tropical and subtropical regions of East and Southeast Asia.
“Spider babies which just hatched out clime up on spider moms’ bellies, to eat a kind of liquid (secreted by spider moms), which was tested to be milk containing four times the protein of cow’s milk. We call it spider milk,” said Chen Zhanqi, a post doctor from Chinese Academy of Sciences.
Researchers found after long-term observation that the newly hatched spider babies feed themselves entirely with the milk in the first 20 days after birth, during which they grow as big as half of their mothers. From 20 to 40 days, spider babies go out looking for food by themselves, while also eating milk from their mothers. This period is a transition for weaning.
The study also found that spider babies don’t leave their mothers after weaning, and continue to stay with them in nests, even after they grow up. This kind of spider will take care of its grown-up offspring, which is seen as a long parental behavioral mode. This mode was once thought to only exist in the social vertebrates with long lifespan.
Experts believe that this breakthrough discovery has extremely important significance for the research on revolution of breastfeeding behavior for contemporary animals. — Reuters