I love interesting little facts, so here are a few inspired by one of my favourite subjects - Lactation!
Further information can be found by following the links at the bottom of the post.
THE MILKY WAY
According to Greek Mythology, the Milky Way was created when Hercules' wet nurse sprayed her milk into the sky and the droplets formed the Milky Way. There are numerous paintings depicting this, the most famous being "The Origin of the Milky Way" by Tintoretto.
The words "Galactic" and "Galaxy" etc, have the same linguistic origin as "Lactation" and "Lactic" etc.
Orangutans only have a baby every 7-9 years. This is because each baby nurses for up to five years and stays in his/hers mother's nest for up to eight years. The mother orangutan devotes everything to one child at a time and will only have another baby when the previous child has become independent enough.
FLAMINGOES' PINK MILK
Flamingoes (both male and female) produce prolactin and secrete a pink milk to feed their chicks. It is full of red and white blood cells and is produced in glands in the upper digestive tract. It feeds the chicks exclusively for two months while their filter-feeding apparatus develops.
Other birds that feed their young on milk are pigeons, doves and some penguins.
Monotremes are the only mammals that lay eggs. There are three types of monotremes - the duck-billed platypus and two kinds of anteater. It is possible that lactation developed as a way to keep eggs moist. Monotremes don't have nipples but they secrete milk from milk ducts through a hairy patch on their tummy. When their eggs are first laid they have three layers of shell. A fourth layer and a coating of a sticky substance then develops afterwards and is thought to be produced by the milk while the mother is incubating the eggs.
Cats knead their owner's lap (as well as cushions or their bed, etc) with their paws because as kittens they kneaded around their mother's nipples to initiate let-down of her milk. The instinct never goes away. When a cat kneads it's paws on you it's because it loves you and looks to you for comfort and protection. A cat that doesn't knead is not a happy cat.