Milk comes from mammals. It's kind of a clear mammal thing. Even our government knows that. And yet, Chinese scientists documented jumping spiders that provide their young drops of fluid rich in nutrients from the mother's body crease. It's the only diet for spiders until they begin to feed, and even then they still drink until they become a little more mature. The results are reported in Science.
The cockroaches and pigeons also give the young substance described as "milk" because it comes from their bodies and gives it an exclusive source of youth maintenance. Tattani mothers share this substance in the mixture, where their embryos develop.
Mothers-mothers and fathers-parents generate cultured milk and feed it with birds for the first few days of life, while babies can not digest real food. Milk of vegetable origin consists of cells filled with nutrients that are poured into flakes from the internal parts of the parental birds that are beneath their necks.
Toxeus magnus here are the jumping spiders to learn and look like ants. Their child protection method also seems to be different from the two examples above. They have a specialized organ that makes milk, according to researchers, made from inanimate eggs that turn into food for surviving offspring.
These spiders also live in small, nuclear nests as a family, where the mother takes care of children even after they become mature. For a while, the young endeavors to feed, but still keep them home, making them even more like mammals.
So this is definitely not breast-feeding, but these researchers think that "it's functional and lactation behavior." It also serves a similar evolutionary need: reimbursement of uncertain access to food and keeping young people in the nest as long as possible to protect themselves from predators.
The spider's spider milk has a protein content of 123.9 mg / ml, four times more than cow's milk. The vegan is not.
Science, 2018. DOI: 10.1126 / science.aat3692 (For DOIs).