Newborns are tiny. That certainly doesn’t come as a surprise. But the relative tininess of some creatures is truly stunning. For example, newborn panda size really made us think about the logistics of things like feeding. These teeny creatures are about the size of a mouse – between three and five OUNCES.
Newborn panda size
For further information on this fun fact and other questions we had about baby pandas, we turned to National Geographic, a trusted source for all things nature (and cited down below).
In 2020, NatGeo wrote about newborn panda size after the birth of a new cub at the zoo in Washington DC. The reason? People wanted to know its sex. But panda cubs are so small that only a genetic test can determine their sex. (It was a boy.)
“That’s not all they’re missing at birth. Newborn giant pandas are almost completely unrecognizable. Rather than sporting their iconic black-and-white markings, pandas emerge from their mothers as pink, wrinkly, blind, squealing creatures roughly the size of a stick of butter,” noted the magazine.
Conservationists who want to save pandas have always had questions about how their size at birth might work for the species, especially since they’re so fragile:
“Pandas are born fragile and underdeveloped. Weighing between three and five ounces, newborn pandas are 1/900th the weight of their mother. This places them among the smallest newborns compared to their mother of any mammal: Human mothers are only about 20 times heavier than their babies, and killer whales are 50 times heavier. Only marsupials emerge smaller‚ and that’s because their babies get to hole up in their mothers’ pouches to finish developing. Red kangaroos, for example, are born at 1/100,000th the weight of their mothers.”
Why are baby pandas so tiny?
We’re still trying to figure out what makes a newborn panda size any kind of advantage. (Then again, pandas are notorious for not doing much to keep their species going on their own.)
Researchers have found that the bears gestate for just 1 month! They don’t even have fully developed skeletons. Even their bear relatives that are born very tiny emerge with skeletons, whereas pandas are born a bit “undercooked” (that’s the word used by the authors of a study in the Journal of Anatomy).
Our best guess is related to just how poorly suited panda bears are to…well, life.
“The short gestation likely has to do with the bamboo that makes up most of the bear’s diet, says Laurie Thompson, assistant curator of giant pandas at the National Zoo. Bamboo doesn’t have many nutrients. Rather than expend the enormous amounts of energy needed to grow a fetus, female pandas can focus on developing the high-fat milk that will help their cubs grow outside of the womb.” — WTF fun facts