Using three-dimensional ultrasound technology with the assistance of computer graphics and tiny cameras, an international team of scientists has captured images of animal fetuses in the womb for the first time, documenting their development from conception to birth.
Over the past two years, the researchers have collaborated with dozens of zoos and wildlife sanctuaries worldwide to monitor an elephant fetus for nearly two years (the longest gestation period among mammals).
In dolphins, researchers observed that around eight weeks of gestation, the calf began swimming in its mother’s womb. In the following weeks, it developed its tail, fins, and blowhole before being born a year later, making it easier to adapt to the ocean environment.
A baby elephant in its mother’s womb. This image shows a 12-month-old Asian elephant fetus appearing to take its first steps, ready for life in the outside world. Elephants have a gestation period of 22 months, but by the middle of pregnancy, small details like toenails are already distinctly formed. Unlike humans, newborn elephants retain their body proportions as they grow to adulthood.
A dolphin calf in its mother’s womb. This photo shows a dolphin about six months old resting in its mother’s womb. Dolphins are mammals, yet they give birth underwater. To facilitate the newborn, dolphins can travel thousands of kilometers to warmer waters. After a 12-month gestation period, dolphin calves are born fully capable of survival, equipped with teeth and swimming abilities. Dolphins are considered highly intelligent animals and are closely related to humans. Because of this, they are utilized for various purposes, from entertainment to rescue missions and performing special tasks for the military. With their ability to emit ultrasound waves, dolphins can detect prey under various conditions.
A puppy in its mother’s womb (Photo: TTO)
Two bear cubs cuddling in their mother’s womb, already showing characteristics similar to their parents. The gestation period for this species is relatively long, lasting from 195 to 265 days. In autumn, pregnant female bears move inland to dig dens in preparation for giving birth. The cubs are born in December or January, usually twins, sometimes triplets, though this is rare. At birth, they weigh only 600-700 grams and have not yet opened their eyes. The cubs grow rapidly on their mother’s milk, which is rich in vitamin A. By 26 days old, they can hear, but they will not open their eyes until a week later.
A leopard cub in its mother’s womb. This species does not have a fixed breeding season; instead, they can become pregnant year-round. The gestation period lasts 91-111 days, and females can give birth to up to four cubs, with two being the most common. Even at two months old, spots have already formed on the coat of this leopard cub. At birth, the cubs are still blind and can only see after about two weeks. They will stay with their mother for about two years before leaving to establish their own territories.
A lion cub in its mother’s womb. According to scientists, during the breeding period, each pair of lions can “mate” 20-40 times a day for four consecutive days. Some documents even record that certain pairs of lions have mated up to 86 times a day. The gestation period for this species typically lasts about three months.
A chihuahua puppy in its mother’s womb. Looking like a small bear but with half the gestation period, chihuahuas already possess basic dog characteristics. However, after birth, the shape of these animals will continue to develop, with a more pointed snout. The teeth of adult chihuahuas also become harder and sharper compared to their juvenile teeth.
Thanks to ultrasound, we can see the image of a penguin chick inside its eggshell. The penguin is curled up, floating in the fluid. The first feathers have already formed, preparing for the chick before it enters the outside world. The gestation period for penguins is about 65 days. After the egg hatches, the mother continues to warm the chick to help it acclimatize to the cold external environment.
A penguin chick still inside the egg. Although penguins are egg-laying animals, the chick also undergoes a growth and development process to mature. However, this growth process occurs within the eggshell thanks to the temperature from the parent birds’ bodies. Similar to mammals, penguin chicks are also surrounded by a liquid medium inside the eggshell.
A baby snake in its mother’s womb. Ultrasound has allowed scientists to discover the secret world of snakes in utero. Young snakes share many characteristics with lizards and birds; even at just a few weeks old, they have formed clear brain and spinal cord regions. This marks a preparation for entering life outside.
A tiger shark pup in its mother’s womb. Tiger sharks are among the most fearsome sharks in the world. Once born, they quickly develop into one of the ocean’s most dangerous predators. Even in the womb, they exhibit their predatory nature by eating their unborn siblings if necessary, using their sharp newly formed teeth.
A foal in its mother’s womb. Horses typically give birth about once every five and a half years, resulting in fewer foals compared to other domesticated animals. Additionally, raising horses requires more meticulous care.
A kitten in its mother’s womb.
A puppy in its mother’s womb.
