My Science School

Vipers are a large family of snakes; the scientific name is Viperidae. They are found all over the world, with the exceptions of Antarctica, Australia, New Zealand, Madagascar, north of the Arctic Circle and island clusters such as Hawaii. 

The family Viperidae includes adders, pit vipers (like rattlesnakes, cottonmouths and copperheads), the Gaboon viper, green vipers and horned vipers. 

All vipers are venomous and have long, hinged fangs. "Generally more venomous vipers are in tropical areas, particularly South America and Africa," said Alan Savitzky, a professor of biological sciences at Utah State University specializing in the biology of snakes. Vipers found in colder, northern climates, such as the black or European adder have more moderate venom. 

Vipers range widely in size, though are generally stocky with short tails. One of the world’s smallest vipers is the Mao-Lan pit viper (Protobothrops maolanensis), which was discovered in China in 2011. They are less than 2 feet (61 centimeters) long, according to National Geographic. The longest viper — and the longest venomous snake in the Americas — is the South American Bushmaster (Lachesis muta), which grows to more than 11 feet (335 cm), according to the University of Michigan’s Animal Diversity Web (ADW). 

Almost all vipers have a distinctive triangular head, according to Discover magazine. This head shape is due to the placement of their large venom glands in the mouth. Some nonvenomous species have evolved a similarly shaped head in order to potentially trick predators into thinking they are vipers. Additionally, most vipers have keeled scales, vertically elliptical pupils and coloring and patterns that serve as camouflage. 

Vipers are known for their extreme fangs, which are long, hollow, hinged and rotatable, according to an article in the journal Physiological and Biochemical Zoology. These fangs connect to venom glands located behind the eyes at the back upper part of the jaw. Venom travels down through the follow teeth to be injected into prey as the viper bites. 

Vipers can rotate their fangs together or independently, which allows them to wait until the last second to erect their fangs. Their mouths can open nearly 180 degrees so the ability to rotate their fangs within that space is an advantage. When not in use, vipers’ hinged fangs fold up and lie against the roof of the snake’s mouth. This allows their fangs to grow relatively long, according to Andrew Solway, author of "Deadly Snakes" (Heinemann-Raintree, 2005).

Vipers can extend their fangs and bite without injecting venom. This is known as a dry bite and is common in human snakebites. Dry bites enable vipers to conserve their previous venom, which can run out and takes a while to replenish, according to an article in the journal Tropical and Geographical Medicine. 

Credit : Live Science 

Picture Credit : Google

Black mamba is species of mamba snake known for its large size, quickness, and extremely potent venom. It lives in sub-Saharan Africa and is one of the continent’s most dangerous snakes.

The average black mamba is 2–2.5 metres (6.6–8.2 feet) long, with a maximum length of 4.3 metres (14 feet). Despite its name, the snake is not black. Instead, it ranges in colour from gray to dark brown, with a lighter underside. The black actually refers to the colour of the inside of its mouth; green mambas and other snakes have white mouths. The black mamba is found in rocky savannas and lowland forests. Unlike the other mamba species, the black mamba is not primarily arboreal, preferring the ground, where it often sleeps in termite mounds or tree hollows. One of the fastest snakes, it is capable of speeds of more than 12 miles (19 km) per hour. The black mamba typically lays 6 to 20 eggs. Prey consists primarily of small mammals and birds.

Although it has an aggressive reputation, the black mamba is generally shy and nervous, and it will use its incredible speed to escape threats. However, if disturbed or cornered, the snake may rear up and threaten with an open mouth and a slightly expanded or flattened neck (or hood) before striking; once a black mamba attacks, it will bite its victim repeatedly. Its extremely toxic venom—two drops of which will reportedly kill most humans—attacks both the nervous system and the heart. Even though most bites are fatal, it is responsible for only a small number of deaths annually, and unprovoked attacks on humans have not been proved. In the wild, black mambas will typically live at least 11 years, while those in captivity have life spans of more than 20 years.

Credit : Britannica 

Picture Credit : Google

Lobster is an invertebrate that belongs to the crustacean family, living in the oceans across the world.

There are two kinds of lobsters - clawed and spiny. Clawed lobsters have claws and inhabit cold waters, while spiny lobsters have antennas instead of claws and inhabit tropical waters.

It has10 legs and a long tail with a fan-like tip. Its body is protected by a shell, which it sheds and grows periodically. Its diet includes fish, molluscs, worms, and crustaceans. Occasionally, it consumes algae and sea vegetation.

Lobsters eat voraciously after molting, and will often consume their own recently emptied shells. Eating the old shell replenishes lost calcium and hastens the hardening of the new shell.

 Lobsters were once considered poor man’s food. In Colonial times the crustaceans were so plentiful in the northeast that they were often used as fertilizer, feed for farm animals, and as fishing bait. Because they were so cheap, they were only eaten by poor people and served to prisoners and servants.

Picture Credit : Google

Can you believe that there are sharks that can live for over 400 years? Greenland sharks have the longest known lifespan of all vertebrates on Earth. Scientists estimated the age of a Greenland shark to be about 400 years in 2016. It is said that they do not even reach sexual maturity until they are about 150 years old.

Greenland sharks are rarely encountered by humans. They are thought to prefer colder, deeper environments but may be found anywhere between the sea surface and depths of 2,200 meters (about 7,200 feet). Greenland sharks are slow-moving, typically swimming at rates of less than 3 km (about 1.9 miles) per hour. They are carnivorous, and their diet is often made up of several different types of fishes, including smaller sharks, eels, flounders, and sculpins. Crustaceans, seabirds, and carrion—as well as terrestrial mammals (such as horses and reindeer) that likely fell through the ice—have been found in stomach analyses of the species. Greenland sharks are not considered dangerous to humans, in part because they live in regions where people do not typically swim; the only known report of a possible attack by a Greenland shark on a person dates to 1859.

Greenland sharks are considered to be a near-threatened species by the International Union for Conservation of Nature. The species was valued for its liver oil; about 114 litres (30 gallons) of liver oil can be obtained from a large specimen (see also fish oil). (Although the flesh of the Greenland shark may be eaten, it is toxic unless properly cleaned and dried or repeatedly boiled prior to consumption.) Greenland sharks were fished commercially from the 19th century until 1960. Norway persecuted Greenland sharks during the 1970s, because they were considered to be a nuisance that threatened other fisheries. In the early 1900s as many as 30,000 Greenland sharks were caught a year. In the present day the annual take is far smaller; small-scale subsistence fisheries in the Arctic harvest fewer than 100 individuals annually, and roughly 1,200 are caught accidentally in fishing trawls.

Credit : Britannica 

Picture Credit : Google

Anaconda, (genus Eunectes), either of two species of constricting, water-loving snakes found in tropical South America. The green anaconda (Eunectes murinus), also called the giant anaconda, sucuri, or water kamudi, is an olive-coloured snake with alternating oval-shaped black spots. The yellow, or southern, anaconda (E. notaeus) is much smaller and has pairs of overlapping spots.

Green anacondas live along tropical waters east of the Andes Mountains and on the Caribbean island of Trinidad. The green anaconda is the largest snake in the world. Although anacondas and pythons both have been reliably measured at over 9 metres (30 feet) long, anacondas have been reported to measure over 10 metres (33 feet) and are much more heavily built. Most individuals, however, do not exceed 5 metres (16 feet).

Green anacondas lie in the water (generally at night) to ambush caimans and mammals such as capybara, deer, tapirs, and peccaries that come to drink. An anaconda seizes a large animal by the neck and almost instantly throws its coils around it, killing it by constriction. Anacondas kill smaller prey, such as small turtles and diving birds, with the mouth and sharp backward-pointing teeth alone. Kills made onshore are often dragged into the water, perhaps to avoid attracting jaguars and to ward off biting ants attracted to the carcass. In the wild, green anacondas are not particularly aggressive. In Venezuela, they are captured easily during the day by herpetologists who, in small groups, merely walk up to the snakes and carry them off.

Green anacondas mate in or very near the water. After nine months, a female gives live birth to 14–82 babies, each more than 62 cm (24 inches) in length. The young grow rapidly, attaining almost 3 metres (10 feet) by age three.

Credit : Britannica 

Picture Credit : Google

If you thought it would take just a day for a snake to digest its meal, you're wrong. A snake can take up to five days to digest its last meal. With larger snakes such as anacondas, the digestion period is weeks rather than days.

The typical 4-5 day digestive process in snakes encompasses the entire feeding process, from striking and swallowing to excreting feces.

The larger the snake, the longer it takes to digest its food. Big snakes eat larger prey, and larger prey takes longer to fully digest. It can take a large snake a week or more to digest prey.

Snakes have stomach acid and enzymes that break down prey. Once this process is completed, the food is moved on to the gut for further nutrients to be extracted.

Snakes can take a longer or shorter time to digest their food. Some constrictors can eat a meal, fully digest it, and defecate in only one day. Others will go longer, up to two weeks, for reasons which vary but include temperature and the availability of food.

Credit : Snakes for Pets

Picture Credit : Google

Legless lizards look a lot like snakes, but aren't. Most of their body is actually tail and they have tiny vestigial limbs and a non-forked tongue. Unlike snakes, they have eyelids and external ear openings.

All this being said, there are a few ways to tell snakes apart from the majority of legless lizards. For example, snakes tend to have relatively longer bodies and shorter tails than their limbless reptilian cousins. Further, serpents don't have eyelids or external ears, while most lizards do. And many "legless" lizards actually have tiny vestigial limbs, while snakes generally sport no external appendages at all.

There also tend to be big ecological differences between snakes and limbless lizards. Most serpents take relatively big prey items on an infrequent basis, while lizards tend to eat large numbers of small creatures such as insects.

But you can't always rely on these guidelines. Pythons and boas, for instance, have rudimentary hind limbs that males use during courtship and mating. And the species that I studied in grad school — Burton's legless lizard, Lialis burtonis — has no eyelids, just like a snake. It eats like a snake, too, attacking other lizards up to half of its own weight, choking them out and swallowing them whole. 

Credit : Live Science 

Picture Credit : Google

Mangoose is a small predatory carnivore, found predominantly in Africa and some parts of South Asia. Most species have greyish or brown fur, while others have a striped coat and a ringed tail. It has a long body with short legs and a tapered snout.

It is a fast and agile creature, noted for my bold attacks on venomous snakes such as king cobra. It lives in abandoned burrows. Some of them are solitary, while others live in large groups.

It feeds on rodents, birds, reptiles, frogs, insects, and worms. Mongooses are mainly carnivorous, but they are known to supplement their diets with plant matter. Despite their defenses against venomous snakes like cobras, they often target smaller, simpler animals as prey.

Mongooses belong to the taxonomic family Herpestidae, which includes some 30 species across 20 genera. They are native to Africa, Asia, and southern Europe, but some species have also spread beyond their native range. They vary in size from the dwarf mongoose, which measures about 8 inches long and weighs less than a pound, to the white-tailed mongoose, which can grow up to 2.3 feet in length and weigh 9 pounds.

Picture Credit : Google

Did you know the mongoose is one of the rare animals that is immune to a dose of snake venom? It is known for its ability to fight and kill snakes like cobras. But how is it possible? Besides being agile and having thick coats, mongooses have specialised acetylcholine receptors that make them tolerate a certain amount of snake venom.

Mongooses evolved in Africa in two distinct groups (genera), one of which, including the meerkats, stayed on in Africa. The other went globetrotting – first to Spain, then South Asia, including India. There are six species found in India; four mainly stay in the forests of the Western Ghats, the other two – the Indian grey mongoose and the small Indian mongoose – have more or less spread everywhere and adapted their lifestyle to live alongside us, enjoying scrub jungles, fields, villages and even the desert.

At around 3 ft long, the Indian grey mongoose is the larger of the two and is the one to have made its name as a cobra killer. Its technique is simple: dart and feint at the snake at ninja speed, so that the latter is forced to strike repeatedly, until it is fagged out. Then, bite its head. Apart from cobras, it hunts rats, mice, ground-nesting birds, lizards, even hares and insects, while its smaller cousin goes for insects, fruits and tubers. It’s been believed that the mongoose is immune to cobra venom, but this is not exactly true. It does have some resistance to the venom, but it simply avoids being bitten with its ninja moves. Also, it frizzes up its fur stiffly, to become twice its size and makes it difficult for the snake’s strike to hit home. It’s a fearless hunter and attacker, plunging headlong at its victim and biting its head – no sly ambush from the rear here. Or, it will stalk its victim, and, when close enough, pounce. Or, it will follow its prey to its burrow and dig it out – for which its huge front claws are perfect. Let one loose in a hen-house and it will cause carnage, killing left, right and centre, far in excess of its needs – and, like a complete reprobate, guzzling up the blood.

Credit : The Indian Express

Picture Credit : Google

Ants are social animals. They communicate with each other using a chemical scent called pheromones. They rely on pheromones to defend territories and exchange information such as the location of food sources and nest sites. Like other insects, ants perceive smells with their long and thin antennae. The antennae provide information about the direction and intensity of scents.

In species that forage in groups, a forager marks a scent trail to find its way back to its colony - similar to Hansel from Hansel and Gretel leaving a trail of bread crumbs through the woods to find his way back home. On the way back to the nest carrying food, the ant creates a trail with an even stronger scent. This trail is followed by other ants. These followers then reinforce the trail when they head back with food to the colony. Thus ants are often seen marching one after the other.

Picture Credit : Google

The sighting of a striped hyena in the Asola Bhatti Wildlife Sanctuary on the Delhi-Haryana border recently made headlines. Why?

The striped hyena is a near-threatened species with less than 10,000 of them in the wild globally. It is one of the least known large camivore species", and since it is a nocturnal creature, its sighting is rare. It is found in several African and Asian countries, including Nepal and India. The last time a striped hyena was sighted in Delhi was under tragic circumstances-it was killed in a road accident in 2015. On several occasions, pugmarks were found in the Aravalli j forests spanning the neighbouring regions of Gurugram and Faridabad too. It is said that during 2017-2018, pugmarks of a striped hyena were found in the Asola sanctuary. And finally comes this sighting at the sanctuary through camera trap. Interestingly, a striped hyena was spotted for the first time since 2017 in Uttarakhand's Corbett Tiger Reserve this August. So why are such sightings important?

"It's a scavenger and plays an important role in maintaining the stability of a forest ecosystem. The presence of a striped hyena in Asola indicates an improvement in the Asola forest." As a scavenger (an animal that consumes dead organisms), it helps clean up the surroundings, decreasing the chances of potential spread of infection. Since scavengers usually feed on kills left behind by larger predators, the presence of a striped hyena is also indicative of the presence of predators such as leopards and tigers. The sighting is also significant because it gives hope at a time when the number of striped hyenas is decreasing due to several reasons such as habitat loss, death due to accidents, etc.

Picture Credit : Google