Discover the special thing inside the mother kangaroo's bag

The image of baby kangaroos often in the bag in front of the mother kangaroo is quite familiar, the bag protects and nurtures the young. Mother kangaroos secrete nutritional compounds inside the pouch with a special mechanism.

Although many marsupials raise their young in pouches such as opossums, Tasmanian devils and even koalas, the kangaroo is certainly the most familiar of all. So what's inside the kangaroo's bag?

The kangaroo's bag is like a hoodie worn backwards.

From the outside, the kangaroo's bag looks like a baby support belt, nothing special. However, its structure is complicated and the function of lactation is special.

Rick Schwartz, animal care supervisor and national spokesman for the San Diego Zoo, says the kangaroo's bag is like a hoodie worn upside down. The hood of the shirt is the pocket and the drawstring is the mother's muscles to open and close it. "The bag will open a little bit if the kangaroo wants it," says Schwartz.

Inside the bag is the texture of kangaroo skin, but no fur. Schwartz says it's soft and comparable to the skin on the inside of one's wrist. The inside of the bag is very warm, equivalent to a mother's body temperature of about 40.5 degrees Celsius. Therefore, baby kangaroos can sweat while in it.

The pouch holds four nipples or milk ducts. When a mother kangaroo gives birth after 32 or 33 days of pregnancy, her cubs are still very young, not yet developed. It is about the size of a jellyfish, weighing less than a gram.

Female kangaroos can give birth to up to 4 cubs in a year or so from just one mating. She can give birth to one child, then her body will delay the implantation of the next embryo until the first is a few months old and has spent time outside the sac. The special thing inside the bag are self-adjusting nipples that secrete nutrients appropriate for the age of the baby kangaroo.

Rick Schwartz said: "The mother kangaroo's body has a special structure, one nipple makes the right kind of milk nutrients for an 8-month-old baby and the other nipple can make the right nutrition for the baby, said Rick Schwartz. Infant".

Schwartz says the baby kangaroo stays in the pouch for about four and a half to five months before emerging, and then it begins to explore the world around it.

Over the next few months, it began to explore further and for longer periods of time. Baby kangaroos are weaned between 10 and 12 months, at which point they no longer enter the pouch.

During the process of raising babies in the pouch, the mother kangaroo needs to do some cleaning. To clean the bag, the mother has to bend her head to look inside the bag and use her tongue to remove dirt.