My Science School

You may not have seen a skunk in your neighborhood, but you've probably smelled one. Their smelly spray, called musk, is not easy to ignore!

The spray, which comes from two glands near the base of the skunk’s tail, can hit a target 12 feet (3.7 meters) away. If you are lucky, you may get a warning before being sprayed. If threatened, skunks stamp their front feet, lift their tail, and growl. Some species of skunk even spring into a handstand before spraying, which puts the skunk's warning markings on full display. If the person or animal doesn’t retreat, the skunk aims the spray at the eyes, allowing the skunk to escape. The spray can remain on its target for days.

Skunks are nocturnal, which means they search for food at night and sleep in dens lined with leaves during the day. Their favorite foods include fruit and plants, plus insects, bird eggs, small rodents, and birds. Birds like the great horned owl prey on skunks. Scientists believe it’s because the birds don’t have a very good sense of smell, which makes the skunk’s spray useless in an attack.

Credit : National Geographic Kids

Picture Credit : Google

As you sweat, the water evaporates into the air and cools the skin beneath it. Unfortunately, pigs have very few sweat glands, and the ones they do have don't work very well.

As a result, pigs can't sweat like we do. So what's a pig to do when it gets hot?

You guessed it: wallow in the mud! Rolling around in the mud helps to keep pigs from overheating when it gets too hot outside.

Some pig farmers now use water sprinklers instead of mud to keep pigs cool in warm months. Mud, however, tends to keep pigs cooler longer because the water in mud evaporates more slowly than pure water.

Just because pigs like to roll in mud, don't assume that they're dirty animals. To the contrary, pigs tend to be very clean animals.

For example, if you spend much time around a pig farm, you'll find that pigs keep their “bathroom" as far away as possible from the areas where they eat and drink.

Since they spend a lot of time outside, rolling in the mud does have other benefits. You've probably noticed that most pigs are not very tan. In fact, their light pink skin can get sunburned very easily.

To help protect their skin from sunburn, pigs use mud as a form of sunscreen. When mud dries on their skin, it forms a barrier against the sun's harmful ultraviolet rays.

A good thick layer of mud also helps to protect pigs from insects. Flies, parasites, and biting insects are often drawn to the areas where pigs live since there is often food nearby. Mud helps to keep harmful insects away from pigs' sensitive skin.

Credit : Wonderopolis

Picture Credit : Google

Meerkats will stand on their back legs for a few reasons. Meerkats will use the increased height to survey their surroundings, calling out to other group members if any predators are close by. They also use this position to get extra heat and to defend their territories from other groups of meerkats.

Meerkats live in groups of as little as three members, to larger ones ranging up to 30 members. These small animals are among the few that can live in such large groups successfully. A meerkat family group is referred to as a mob, a gang, or a clan.

Many people are familiar with the upright position of a meerkat. You will either see one meerkat or a group standing together. Animals, whether big or small, have distinct behavior, and there is a reason for this. Meerkats stand to attention for a few different purposes.

Being such small mammals, meerkats are susceptible to all kinds of predators. Due to being so small, the meerkat has to search for food quickly. By searching for prey quickly, they spend much less time in the open and away from predators. Meerkats will try to get back to their burrows very quickly. The burrows protect them from their natural predators. 

The aerial predators of a meerkat are large birds such as eagles and hawks. The meerkats also need to look out for predators on the ground. There are many terrestrial predators, including animals much larger than them, such as jackals.

The meerkats know that having one or more meerkats standing guard means that they can concentrate on foraging for food.

Credit : North American Nature

Picture Credit : Google

Jellyfish are transparent and made up of 95 percent water, so you’d think there isn’t much to them. But you’d be wrong. Jellyfish are more complex than you’d think—and one of their most fascinating parts is their stinging cells. Located on their tentacles, jellyfish's stinging cells are called cnidocytes. They are small compartments that house a mini needle-like stinger. When an outside force triggers a stinger, the cell opens, letting ocean water rush in. This causes the stinger to shoot out into what triggered the action; once it’s there, venom is released. All of this happens within a millionth of a second. Though the venom of most jellyfish is not harmful, some can be deadly. For example, the Indo-Pacific box jellyfish—or sea wasp—releases venom that makes the heart contract. There is an antidote, but the poison acts fast, so someone who is stung must seek medical attention immediately.

People may come into contact with the nematocysts of a jellyfish when they are swimming in the ocean or walking on the beach. This contact can cause the venom from the nematocysts to be injected into the body. More than 150 million jellyfish stings happen in the world each year.

Depending on the type of jellyfish and how much of the skin touches the venom, the sting can cause pain or other serious health problems. Some jellyfish stings can be life-threatening. It is important to get medical help if you have severe symptoms after a jellyfish sting.

Credit : Cleveland Clinic

Picture Credit : Google

­It's possible to die from a wound inflicted by a dead stingray, but it's also highly unlikely.­ The movement of the tail is what brings the barbed spine to an erect position and causes the venomous barbs to tear through the integumentary sheath. In other words, there is no muscle controlling the spine or barbs; they become a threat as the result of the tail's movement, somewhat like the motion of a folding knife springing from its cradle with a flick of the wrist.

This means that a dead stingray shouldn't be able to create the laceration needed to envenomate a person -- unless it died while in a defensive stance. If the spine was erect and ready for destruction, but hadn't met its mark when the stingray died, then it would still present a threat if someone handling the dead stingray punctured his or her skin with the spine.

Stingray venom is serious stuff. In large enough doses, it can affect the heart's electrical functioning and either dilates or constricts blood vessels. The venom won't make it to the heart in most cases; it will usually hang around the wound site, causing tissue necrosis, or cellular death. There is some relief available for the pain: Soaking the wound in very hot water has been shown to soothe the ache created by stingray venom. Bacterial infections are also common, so you may need to take some antibiotics in the event of stingray sting. It's also highly recommended that anyone suffering a sting from a stingray seek medical attention. Stingray venom persists without medical intervention; the damage it causes to the soft tissue doesn't go away on its own.

Picture Credit : Google

Though leopard seals obtain all of their food resources from the water, they must come ashore to pup and to care for their young. Unlike other species of Antarctic seals, which mate on land or on the ice surface, leopard seals mate in the water. The males apparently do not visit the pupping areas and do not participate in parental care. Pupping and nursing both take place on the ice surface, rather than on ice-free shores.

Leopard seals are perhaps most well known for their predation on Antarctic penguins. They wait at the ice edge for penguins to enter the water to feed and then aggressively chase them for a quick meal. Young penguins, especially those entering the water for the first time, are particularly vulnerable to predation by leopard seals. Though penguins do make up a large part of their diet during some seasons, the Leopard Seal’s diet is more heterogeneous than one might expect. They are known to eat fish, squid, krill, and juveniles of other seal species, in addition to penguins. Killer whales are the only species known to eat leopard seals.

Like most Antarctic species, the remote nature of the leopard seal’s home range keeps human interactions to a minimum. Though they are known for their aggressive behavior, they only very rarely aim that aggression towards humans. There are currently no strong human threats to this seal, and scientists generally consider it to be a species of least concern. However, potential impacts of expanding Southern Ocean fisheries and ongoing climate change on the populations of leopard seals are not well known, so it is important to continue to study and monitor this and other Antarctic seals.

Credit : Oceana

Picture Credit : Google

Dolphins are able to protect vulnerable members of their pods and extended families such as young dolphins and injured or sick dolphins. Dolphins use their strong snouts as a powerful weapon to ram sharks, targeting their soft underbellies and gills to cause injuries.

Sharks pose less of a threat to larger members of the dolphin family. Indeed, orcas are the top predator in the ocean and small sharks are a target for some populations. Orcas will even attack and kill great white sharks just to eat their livers which are a high energy food source.

When dolphins are hungry, they turn into calculating predators who are capable of developing unusual methods to trap their prey. For instance, dolphins that live in the shallow waters of Florida have been observed using their tails to kick up mud in a circular formation in order to trap fish inside, while dolphins who live in Shark Bay, Australia, have been seen using sponges as tools to dig up prey from the seafloor.

What's more, dolphins are able to communicate these tactics with other dolphins, which means they're always improving their skills. According to the Smithsonian, "dolphins learn different tricks for catching food from one another in a kind of cultural transmission."

Dolphins have sharp teeth that they usually use to rip apart their prey. Bottlenose dolphins, for example, have between 80 and 100 teeth that they use to grab, grip and secure their prey.

However, the creatures can (and do!) bite humans on occasion. Because of the potential danger, officials at the Commerce Department's National Marine Fisheries Service have even released fliers with warnings that "dozens of bites have been reported" and "people have been pulled underwater" by the animals. In fact, as recently as 2012, an 8-year-old girl was infamously bitten by one of the animals at SeaWorld.

Picture Credit : Google