Nearly half of the 133 captive births recorded before 1998 were of twins, but panda mothers are typically unable to care for more than one infant. For the first two to three weeks of life, the mother uses her forepaws and her thumblike wrist bones to cuddle and position the infant against herself in a rather uncarnivore-like and almost human fashion. Relative to the mother, giant pandas produce the smallest offspring of any placental mammal (about 1/800 of the mother’s weight). Altogether, gestation averages 135 days (with a range of 90–184 days), but, because of the short growth phase, a term fetus weighs only about 112 grams (4 ounces) on average. Hormone levels in females’ urine indicate that the period of embryonic/fetal growth and development lasts only about two months. Like bears, giant pandas undergo a delay in implantation of the fertilized ovum into the wall of the uterus, a period of two to three months after mating. Giant panda cub ( Ailuropoda melanoleuca) At this time males may become highly aggressive as they compete for the opportunity to mate. Assemblages of one to five males per female have been recorded. Males appear to locate females first by scent and ultimately by vocalizations. A spring mating season (March–May) and a fall birth season (August–September) are seen in both wild and captive populations. Except for the mothers’ care of infants, the only social activity of pandas takes place during females’ estrus, which occurs annually during the spring and lasts one to three days. ![]() Males appear to use scent to identify the areas where they live, whereas females primarily use it for signaling estrus. Chemical analysis of marks is consistent with a difference in function for males and females. The gland is rubbed against trees, rocks, and clumps of grass, with scent conveying information on identity, sex, and possibly social status of the marking individual. A large scent gland located just below the tail and surrounding the anus is used to leave olfactory messages for other pandas. Under this arrangement scent functions in regulating contact between individuals. Each animal confines its activities to a range of about 4 to 6 square km (1.5 to 2.3 square miles), but these home ranges often overlap substantially. The giant panda’s solitary nature is underscored by its reliance on its sense of smell (olfaction). Bamboo is the healthier diet for captive pandas. The species cannot naturally survive outside bamboo forests, though in captivity they have been maintained on cereals, milk, and garden fruits and vegetables. Although unable to capture prey, pandas retain a taste for meat, which is used as bait to capture them for radio collaring and has made them pests in human camps on occasion. Fossilized dental remains indicate that the giant panda committed to bamboo as its principal food source at least three million years ago. As much as 16 out of every 24 hours is spent feeding, and elimination of wastes occurs up to 50 times per day. Pandas solve this problem by rapidly passing prodigious quantities of the grass through their digestive tracts on a daily basis. Despite adaptations in the forepaws, teeth, and jaws for bamboo consumption, the giant panda has retained the digestive system of its carnivore ancestry and is therefore unable to digest cellulose, a main constituent of bamboo. SpaceNext50 Britannica presents SpaceNext50, From the race to the Moon to space stewardship, we explore a wide range of subjects that feed our curiosity about space!Īs much as 90–98 percent of the panda’s diet consists of the leaves, shoots, and stems of bamboo, a large grass available year-round in much of China’s forested regions.Learn about the major environmental problems facing our planet and what can be done about them! Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century. ![]() 100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.COVID-19 Portal While this global health crisis continues to evolve, it can be useful to look to past pandemics to better understand how to respond today.Student Portal Britannica is the ultimate student resource for key school subjects like history, government, literature, and more.This Time in History In these videos, find out what happened this month (or any month!) in history.#WTFact Videos In #WTFact Britannica shares some of the most bizarre facts we can find. ![]()
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