Snakes are believed to have evolved from lizards, with the first specimens appearing in the fossil record between 143 and 167 million years ago during the Jurassic period. They diversified and modern snakes emerged after the extinction of the dinosaurs 66 million years ago.
Now there are more than 3,000 species of snakes on the planet, 600 of which are poisonous.
They are one of the most dangerous animals on earth. The World Health Organization estimates that between 80,000 and 138,000 people die each year from snake bites.
Snakes are believed to have evolved from lizards, with the first specimens appearing in the fossil record between 143 and 167 million years ago during the Jurassic period. They diversified and modern snakes emerged after the extinction of the dinosaurs 66 million years ago.
Now there are more than 3,000 species of snakes on the planet, 600 of which are poisonous.
They are one of the most dangerous animals on earth. The World Health Organization estimates that between 80,000 and 138,000 people die each year from snake bites.
The size of snakes varies widely between species, with the smallest measuring only about four inches long. But what is the biggest?
Longest snake
Graham Alexander, a professor of herpetology at the University of Johannesburg in South Africa, told Newsweek that a snakebite should always be taken "with a pinch of salt", as they are often overdiagnosed.
However, he said that no other snake can match the length of the reticulated python. "I've seen reticulated pythons in Southeast Asia that were over 19 feet tall," he said. "They are massive snakes, without exaggeration."
The reticulated python has an average length of 20 feet, making it the longest snake in the world.
It is native to South and Southeast Asia and can be found in rainforests, forests and surrounding grasslands. The python is a good swimmer and in some cases has been found far away from the sea.
Alexander said: "We must remember that captive specimens may have the potential to reach larger sizes than wild ones due to a stable food supply and lack of prey in captivity.
"I know there are a few cases of Burmese pythons and reticulated pythons reaching lengths of about 26 feet in captivity. These are truly extraordinary."
Pythons are non-venomous and kill their prey by suffocation. They use a striking motion to wrap themselves around their prey, squeezing a little more tightly each time the prey exhales.
Alexander noted that while pythons can be very large in length, the threat they pose depends on their evolutionary history with humans: "Giant pythons in Asia, such as the Burmese and reticulated pythons, sometimes attack humans. They have not had as long an evolutionary history with humans as African pythons have.
"In my opinion, African pythons exclude humans as prey because humans are too dangerous—pythons that carry humans usually die, which has taken that taste out of the population. That is in general with anecdotal reports on giant snakes, is a pretty exaggeration."
Heaviest snake
In terms of mass, the green anaconda is no green.
A member of the boa family, green anacondas are non-venomous and use their strong jaws to capture their prey. Then they die before swallowing it whole.
They are also highly aquatic and spend almost all their time in the water. According to Alexander, the green anaconda can sometimes reach over 220 pounds and up to 16 feet in length.
"Maybe there will be exceptional individuals that are quite large but I don't believe reports of 10 m [32.8 ft] snakes in the wild," he said.
"In my opinion, I would not think that there are humans on the anaconda's menu, because anacondas, especially large individuals, ambush from the water in marshy wetlands and are therefore less likely to meet humans there, unless humans are specialized. Researchers are not looking for form. Snakes."
Largest venomous snake
Venomous snakes are smaller in size because they do not have to depend on suffocation in their prayers.
Sikandar said that the king cobra is one of the largest venomous snakes in the world, which grows up to an average of 13 feet. However, there have been reports of it growing up to 18 feet in some reports.
King cobras live in South and Southeast Asia, and are classified as vulnerable because of their low population, despite having an aggressive reputation, the king cobra is actually much more alert than many small snakes.
The king cobra, like many other snakes, attacks in self-defense or to defend its eggs only when it is surrounded. However, its poison can also be fatal. Depending on the power of the venom and how big the prey is, it can kill within 15 minutes.
The Black Mamba is one of the longest venomous snakes in the world and one of the most dangerous snakes in the world.
Nick Evans, founder of the KwaZulu-Natal Amphibian and Reptile Conservation in Durban, South Africa, told Newsweek that the black mamba is the longest snake ever found, reaching almost nine feet in length. There are records of them growing up to 14 feet, although Evans said this is rare.
Black mambas live in South and East African savannas, rocky hillsides and open forests, although with many residential areas being between canyons, this often means they can be found in and around homes.
Evans said that they are extremely misunderstood creatures.
"Before working with him, I was always a little intimidated by him. I had clearly heard a lot about his intimidating reputation. However, after learning to work with him, and working with a few hundred, Now I can see what they're really like, that their reputation is greatly exaggerated," he said.
"They are known to be super aggressive killers. Yes, their neurotoxic venom can certainly be fatal. However, they are far from aggressive. I am constantly chasing them, they are not chasing me . .. the problems start when people try to kill them, or catch them without training."