The most representative mammal of Australia is the animal that we commonly call kangaroo, whose name does not correspond to a taxonomic term. These species belong to the Macropodidae family, which also includes a variety of lesser-known and smaller individuals. Thus, depending on the species, they can be medium to large in size, however, generally the term kangaroo is used to refer to the larger ones, which weigh up to 90 kilos and measure close to two meters in height. Usually, they have nocturnal and twilight habits, while during the day they remain calm..
Kangaroos are quite peculiar animals, showy and can be docile. They are characterized by having a fairly complex reproduction system, as well as a peculiar process of birth and development, considered unique within the animal kingdom. This places them within what are known as marsupials. Continue reading this interesting AnimalWised article and discover with us how are kangaroos born.You may also be interested in: How are seahorses born? Index
- When are kangaroos born?
- How and where are kangaroos born?
- How is the kangaroo bag inside?
When are kangaroos born?
Kangaroos are primarily native to Australia, although they can also be found in New Guinea and nearby islands. These animals are bipedal because they move by jumping with their two hind legs, which are long and narrow, but very muscular and powerful, which allows them to reach speeds of up to 70 km / h. When they move slowly, they use their non-prehensile tail to support themselves and maintain the balance of the body, an aspect that does not occur when they jump, since locomotion in this way is performed very efficiently.
These are relevant data to understand certain aspects of the reproduction and birth of kangaroos. The reproduction of kangaroos it is a unique process within the animal kingdom, since females are capable of maintaining three offspring of different ages and development times at the same time. However, ¿when kangaroos are usually born? The reproductive times of kangaroos can vary from one species to another.. For example, in the case of the red kangaroo (Macropus rufus), the environmental conditions must be conducive to breeding, so that they do so in the rainy season so that, when the calf begins its independence from the mother, there is food available. For its part, the eastern gray kangaroo (Macropus giganteus) and the western gray kangaroo (Macropus fuliginosus), generally procreate year-round, but births occur more frequently in the summer so that the young begin their feeding independence in the spring.
As a curious fact, kangaroos develop a courtship that can last a short time or a couple of days and the males often clash to obtain the right to mate with the female in heat. In this dueling process, the two individuals can fight with their front legs, hence the image of some comics in which we observe two kangaroos boxing. The dominant male may fertilize more than one female in the same season.
Know all the details of the Reproduction of kangaroos in this other article.
How and where are kangaroos born?
Once the female becomes pregnant, she will have a short uterine gestation period. In fact, the gestation of kangaroos is one of the shortest processes in mammals, since it lasts between 28 and 33 days, the latter being the specific period of the red kangaroo. After this time, ¿how and how big are kangaroos born? Well, since the gestation process in the womb is so short, an underdeveloped embryo is born, very small (about 2 cm on average, although it may vary depending on the species), hairless and with eyes and ears still in a premature state.
The baby kangaroo is born through her mother's vagina, as with all placental mammals. The kangaroo birthing process is quick and immediate, without any help and instinctively, the newborn is mobilized by climbing from the vagina to the marsupial bag of the mother, site where it hooks to the nipple of this to start sucking. It will take about eight months for the young kangaroo to start to get out of the pouch and begin to fend for itself. At this time, although she is already beginning to take food on her own, she will be able to eventually return to the pouch to continue breastfeeding.
When the female calves and the child leaves the uterus to move to the marsupial bag, the new mother can become pregnant immediately, starting the development of a new embryo. However, because another baby kangaroo is found breastfeeding, a process known as embryonic diapause, which consists of paralyzing the growth of the new fetus for about 235 days so that the kangaroo in the bag continues to grow. After this time, the embryo is reactivated in the uterus, which coincides with the abandonment of the one in the bag. About a month later, the new kangaroo is born and a third pregnancy can occur, which will follow the same process described. In this way, the same female can have a diapausing embryo in the uterus, a growing baby kangaroo in the marsupium and a third young son who is already moderately independent, but who eventually returns to feed on his mother. In fact, the kangaroo mother has the ability to produce two types of milk: one for the embryo that is developing in the pouch and another for the kangaroo that has already come out of the pouch..
How is the kangaroo bag inside?
The word "pouch " comes from the Latin marsupium and means "bag ". It is a kind of sac that animals called marsupials have and in which the development of the immature embryo that has been born is completed. Unlike the outer fur that covers the body of these animals, the inside of the kangaroo pouch it is a fabric with very little hair, so you can see the skin of a reddened coloration.
The rearing of the baby kangaroo is carried out by means of the pouch. In this way, within this particular structure the breasts of the female are found. Thus, the kangaroo pouch is like an epidermal fold that acts as an incubator for the embryo, where it not only feeds, but also maintains the appropriate temperature, being the ideal space in which it is protected from predators and adverse effects. medium. If a newborn does not enter the pouch within a few minutes of being born, it will inevitably die because, remember, it is an embryo still developing.
¿The male kangaroo has a pouch?
The male kangaroo does not have the pouch or pouch, since it does not need it, unlike females in which their breasts are covered by this sac-like fold, protecting the embryo there so that its development culminates while its lactation period occurs. Once the newborn enters the pouch, it firmly attaches its mouth to the mother's nipple, which expands until it fits snugly into the baby kangaroo's mouth..
The animal world never ceases to amaze us with its fascinating and varied reproduction strategies to guarantee the perpetuation of species in ecosystems. In this article we have learned how kangaroos are born, but each species has its own reproduction and birth mechanism, so we encourage you to consult these other articles:
- ¿How elephants are born?
- ¿How whales are born?
In this National Geographic video we can see what the inside of the kangaroo bag looks like and how the newborn feeds: