Animals that give birth to live young, called viviparous, include most mammals (humans, dogs, cats, whales), many fish (sharks, guppies), some reptiles (certain snakes, lizards), amphibians (some caecilians), and invertebrates (some cockroaches, aphids). This reproductive strategy allows internal development, protecting embryos from external environments, and has evolved independently in many different animal groups, from sharks to snakes to whales.
Here are 10 animals that hatch from eggs and also give birth to live young:
Mammals: Most mammals, including humans, dogs, cats, elephants, whales, and many more, give live birth. Some Reptiles: While most reptiles lay eggs, some, certain species of snakes and lizards, give birth to live young. Some Fish: Certain species of sharks and rays give birth to live young instead of laying eggs.
Backward-aging jellyfish
At the top of our immortal animals list is a tiny variety of jellyfish known as Turritopsis doohmii, or more commonly, the immortal jellyfish. It has found a way to cheat death by actually reversing its aging process, according to National Geographic.
Did you know the longest brooding period or 'pregnancy' of any known animal is a whopping four and a half years? If you think female African elephants have it tough with their 22-month gestation period, spare a thought for the deep-sea octopus Graneledone boreopacifica.
Aphids, tiny insects found the world over, are “essentially born pregnant,” says Ed Spevak, curator of invertebrates at the St. Louis Zoo.
The Amur leopard is one of the rarest big cats in the world, with only around 100 individuals left in the wild.
Jellyfish and comb jellies
This cycle can repeat indefinitely, potentially rendering it biologically immortal. These organisms originated in the Caribbean Sea, but have now spread around the world.
Python. Pythons, the slithery creatures of the wild, are also silent killers. There will be no sound when they slowly creep up to their victims, and in a sudden move they will constrict them, killing them slowly and painfully.
Parthenogenesis occurs naturally in aphids, Daphnia, rotifers, nematodes, and some other invertebrates, as well as in many plants. Among vertebrates, strict parthenogenesis is only known to occur in lizards, snakes, birds, and sharks.
Copperheads are ovoviviparous, meaning they give birth to their young encased in an amniotic sac, rather than laying eggs like many other snakes. After giving birth, a copperhead mother does not care for her young.
7 uncommon animals that produce milk
Like humans and all mammals, cats are born live. They don't hatch from eggs like birds and reptiles. A baby cat is called a kitten. For the first 4-6 weeks of a kitten's life, it can't eat any normal food - it just drinks its mother's milk, so it has to be around her all the time.
Share: Elephants have the longest pregnancy period of any living mammal. If you – or someone you know – has experienced a pregnancy that seemed to go on forever, spare a thought for the elephant. It's the animal with one of the longest gestation periods of all living mammals: nearly two years.
The tubeworm Escarpia laminata that lives in deep sea cold seeps regularly reaches the age of between 100 and 200 years, with some individuals determined to be more than 300 years old. Some may live for over 1,000 years.
I have named the mayfly Dolania americana the shortest lived among the Ephemeroptera with females typically living for less than five minutes (Sweeny & Vannote 1982).
The Northern White rhino is on the brink of extinction. In the chart, you can see the collapse of this beautiful animal's population as a result of poaching, habitat loss, and conflict. Now, only two individuals are left — Najin and her daughter, Fatu.
Elephant. The majestic elephant holds the record for the longest gestational period among land mammals, with pregnancies lasting approximately 22 months.
Watch for signs that bull sea lions are territorial, they will bark, blow bubbles, and show you their teeth when they are warning you to back away. Do not ignore these signs, they mean business.
1. Hyenas. Hyenas are often depicted as dirty, ugly scavengers, yet in the wild, they are the biggest threat to lions. These two species engage in fierce competition over food sources, leading to epic confrontations.