Swimming in an open sea or hiking in a deep forest on a vacation can be fun and exciting especially when you have a chance to visit Australia. Australia is home to vast biodiversity. It is a unique country for those who want adventure and to encounter different cultures, traditions, and of course, animals. About six million visitors come to Australia each year because of its beautiful beaches, unique flora and fauna, friendly and hospitable people, and relaxed atmosphere. Australia has some 9,700 protected nature areas such as national parks and can offer visitors a varried and diverse array of nature-based tourism opportunities. This country is home to more than one million species of plants and animals, many of which are unique. Australia is a “megadiverse” country, and is one of the most biologically rich countries in the world. There are 17 megadiverse countries, comprising a mere 10 percent of the earth's surface, but together accounting for more than 70 percent of its biodiversity. Australian biodiversity has been influenced by the range of environmental conditions in the country. Australia has diverse bodies of water and land which are home to a wide range of species of animals you can only find in the country. One of those is the Australian box jellyfish. The Australian box jellyfish is considered the most venomous marine animal and despite their gentle physical characteristics, they are considered one of the most dangerous species of jellyfishes. Box jellyfish are identified and distinguished by their box-like body. Some species of box jellyfish like the one in Australia produce potent venom delivered by contact with their long tentacles. Unlike other stings from other species, their venom can be fatal to humans. Its name was obviously derived from its physical characteristics and unlike other species, with the help of their form, box jellyfish can move more rapidly. They can swim up to a speed of  6 meters per minute. Its bell or head usually reaches about 6.3 inches (16 cm) in diameter but can grow up to 13.8 inches (35 cm). From each of the four corners of the bell trails a cluster of approximately 15 tentacles where venom can be found. The pale blue bell has faint markings or patterns when viewed from certain angles. If you look closely at its head, you’ll notice its resemblance to a human head or skull which makes it look scarier. Due to its almost transparent color, the creature is nearly impossible to notice in its habitat which makes it more dangerous as you cannot easily avoid contact. When the jellyfish are swimming or floating on the water, their tentacles contract so they are only about 6 inches (15 cm) long and only about 0.2 inches (5 mm) in diameter. But when they are hunting, their tentacles become thinner and extend up to about 10 feet (3 m) long. Their tentacles are covered with a high concentration of stinging cells called cnidocytes, also known as stinging cells. They are specialized cells that contain an “explosive” organelle called cnidocyst that acts as a 600 million-year-old microscopic injection system and is important for prey capture and anti-predator defense. Common to species in the diverse phylum Cnidaria, these cells can launch a toxic barb or blob to enable cnidarians to stun prey or deter invaders. Box jellyfish are active hunters during the day time; while at night, they are seen resting on the ocean floor. Australian box jellyfish have four eye-clusters with 24 eyes. Some of these eyes are quite sophisticate. They have a lens and cornea, and an iris that can contract in bright light, and a retina. Their speed and vision lead some researchers to believe that box jellyfish actively hunt their prey, mainly shrimp and small fish. Although all box jellyfish contain venom and are considered terrors of the sea, they are not dangerous to consume for some marine predators like green sea turtles which are the main predators of box jellyfish. Aside from green sea turtles, other predators are ocean sunfish, gray triggerfish, seabirds, whale sharks, some crabs, and some whales such as humpbacks. They are attracted to light of different colors but blue light seems to elicit a feeding behavior. Interestingly, black objects seem to cause them to move away. They can actually see images, with the aid of light-focusing lenses. A researcher named Anders Garm from the University of Copenhagen has found that the jellyfish always keeps its upper lens eyes pointing towards the sky. They live on a diet of prawns and small fish and are prey to turtles, whose thick skin is impenetrable to the cnidocytes of the jellyfish. Box jellyfish have tentacles covered in biological booby traps known as nematocysts - tiny darts loaded with poison. People and animals injected with this poison may experience symptoms such as paralysis, cardiac arrest, and even death, all within a few minutes of being stung. Although jellyfish can be found in many seas and oceans, box jellyfish can be commonly found in the tropical Indo-Pacific region, the Atlantic Ocean, and the East Pacific Ocean. Some species were recorded to be habituating seas in North California, the Mediterranean Sea, and Japan. In the wild, the box jellyfish will live up to three months but can survive up to seven or eight months in a science lab tank. Studying with different poisonous animals, Hugo Flecker, an Australian medical practitioner, radiotherapist, toxicologist, and natural historian, was concerned at the unexplained deaths of swimmers. He identified the cause of death of a 5-year-old boy after being stung in shallow water at Cardwell as the box jellyfish later named Chironex fleckeri. As he pursued his studies, in 1945, he described another jellyfish envenoming which he named the "Irukandji Syndrome", later identified as caused by the box jellyfish Carukia barnesi. In Australia, critical encounters are most often caused by the largest species of this class of jellyfish, which is one of the world's most venomous creatures. The Australian box jelly, is considered as the largest of the cubozoans. They have caused at least 79 deaths in Australia alone since the first report in 1883. Certain box jellyfish stings can kill a person within minutes while other box jellyfish stings can lead to death in 4 to 48 hours after a sting due to a delayed reaction to the sting. A single box jellyfish creates and contains enough venom to kill more than 60 humans. To a human, a sting will cause necrosis of the skin, excruciating pain and, can even cause cardiac arrest and death within minutes, if the sting is severe enough. The venom of a box jellyfish is not the same as other stingers. It’s a complex concoction of different compounds, none of which are very well understood to this day. Scientists know it contains a multitude of compounds that, when injected together, work very effectively to immobilize and kill their victims. For humans, it can cause permanent scarring of the skin, destroy blood vessels and produce intense muscle spasms that are so severe that muscles of the heart can’t relax between contractions, stopping blood flow. A potent venom is composed of many different components and each acts on a different part of the human body. One component causes localized pain while the other component travels through veins and arteries straight to the heart which usually causes heart failure. After a sting, the pain comes on quickly and continues to get more intense and widespread through the body causing unbearable pain. Australian waters are home to different types of marine life and encounters with box jellyfish and crocodiles are common. To avoid such a painful, and possible deadly encounter, always wear appropriate protective clothing or swim gear. Lycra suits will reduce risk while swimming, especially in the summer months when they are actively hunting at day time. Only swim on patrolled beaches, preferably in netted swimming areas with lifeguards. It’s advisable not to allow children to enter the water without protective clothing, nor to swim unsupervised during the summer danger season. Lastly, be educated in the basic knowledge of rescue and resuscitation from a sting by a box jellyfish. If you are unsure if you were stung by a box jellyfish, some symptoms to look out for are pain, itching, rashing, nausea, diarrhea, swollen lymph nodes, and muscle spasms. For severe incidents, coma or heart failure which leads to death is observed. Victims of a box jellyfish sting must be monitored carefully for several hours after a sting. Some jellyfish species are toxic to humans, while others are safe for human consumption. In fact, jellyfish is commonly consumed in Southeastern Asia, as it's believed to offer several health benefits and is known for its distinct texture and taste. Jellyfish in general can be served hot, cold, cooked or raw. They essentially take on the flavor of the other food or condiments they are served with due to their bland original taste. Jellyfish are commonly cut into strips or thin slices and served in salads, but they can also be used in egg rolls, stir-fry, and sushi wraps. Jellyfish is known for its subtle and delicate, slightly salty, flavor. When it comes to texture, jellyfish have a slimy, slightly chewy consistency. Some Chinese and Japanese cultures often eat them raw or sliced as a salad ingredient. Jellyfish is famous in several Asian and Southeast Asian countries. Edible jellyfish are being exported and imported from countries like Indonesia, Malaysia, Myanmar, the Philippines, Singapore, Thailand, and Vietnam. Jellyfish are often used as an ingredient in various dishes, especially in Asian countries. In several East and Southeast Asian countries, and in some Asian countries,edible jellyfhish is considered to be a delicacy. Edible jellyfish is often processed into a dried product or dehydrated goods. Several types of foods and dishes may be prepared with edible jellyfish, including salads, sushi, noodles, and main courses. Various preparation methods exist and each country in the world has its own specialties. Though it can be cooked in different types of cuisine, dehydrated and pickled jellyfish is considered a delicacy in several Asian countries. China, Korea, Taiwan, and Japan are just a few of the countries that find jellyfish a great delicacy, and is often served on special occasions too. Most species of jellyfish are edible and are a rich source of vitamins and nutrients. They have low calories with high antioxidant properties which prevent cell injury. Dehydrated jellyfish can be prepared for eating by soaking it in water for several hours to rehydrate it, and then parboiling, rinsing, and slicing it. In some Asian countries, Jellyfish salad is a popular dish. It may be prepared using cold marinated jellyfish that is sliced into very thin pieces. In fact, some Asian airlines also serve jellyfish salad as a part of their meals for passengers. In Japan where sushi and sashimi are popular, jellyfish sushi is one of their delicacies. In Thailand where noodles like pad thai dish are considered as a staple dish, they also have an authentic Thai dish using jellyfish as the main ingredient. They have innovated their way of cooking and they gave birth to a crunchy style of noodles made of jellyfish. A Japanese company named Tango Jersey Dairy produced vanilla and jellyfish ice cream. Although jellyfish can be 95% water, they also contain high amounts of biological molecules. 'It's really rich in proteins – basically a superfood for microbes,' said Dr. Tinta. For those interested in collagen intake, you might consider a jellyfish jerky on your next trip to one of the Asian countries mentioned above. Jellyfish are rich in collagenous protein with no crude fat. The collagen from jellyfish has been proven to produce many beneficial effects, including antioxidant, anti-inflammatory, and immune-modulatory activities and lipid-lowering effects. If you are stung by a jellyfish in tropical waters and you experience extreme pain, breathing problems, nausea, vomiting, or sweating, seek medical attention right away. A sting of a jellyfish occurs when its tentacles touch a person’s skin. Stinging cells present on their tentacles, also called nematocytes, penetrate poison into the skin. The type and how severe the sting is will depend on how much of the tentacle touched the skin and the species of jellyfish. In northern Australian tropical waters where box jellyfish are common, stings from these sea terrors can cause a severe and dangerous reaction. The venom from these species is very potent and the tentacles are long and likely to come into contact with more of the skin. Other jellyfish in northern waters can cause “Irukandji syndrome,” where a person experiences extreme pain in their body, not necessarily at the location of the sting. The reaction to human skin may not occur until half an hour after the jellyfish have stung. This type of sting can also be dangerous and may require immediate emergency medical treatment. The most common type of jellyfish sting comes from the bluebottle jellyfish. Bluebottles are also called Portuguese Man-of-War, and can be found up and down Australia’s coastline. The Portuguese man-of-war was named after its resemblance to 18th-century Portuguese warships. After a sting from Portuguese Man-of-War, their tentacles leave long, stringy red welts on the skin. There is local pain, burning, swelling, and redness. The welts last from minutes to hours. A rash may come and go for up to 6 weeks. While the man-of-war's sting is rarely deadly to people, it packs a painful punch and causes welts on exposed skin. Beachcombers are warned: The stalwart man-of-war may still sting you even weeks after having washed ashore. These stings are painful. However, it is uncommon to require medical attention after being stung. If you're stung by a Portuguese Man-of-War, don't panic. The sting, while very painful, is not likely to be life-threatening. Experts recommend pouring vinegar on the wound to help deactivate the venom and then immersing the area in hot water. Use water that's 110 to 113 F (43 to 45 C). It should feel hot, not scalding. Keep the affected skin submerged or in a hot shower until the pain subsides. This may take as long as 20 to 45 minutes. Apply hydrocortisone cream or ointment twice a day to the affected skin. Some locals, use vinegar to stop the venom from the sting. Be sure not to use ammonia, urine, rubbing alcohol, freshwater or ice. All of these treatments can trigger the release of more venom. If vinegar is not available, scrape the stingers off of the affected area. Portuguese man-of-war stings may cause blisters or small, shallow sores on the skin. At the site of the stings, the skin may look dusky or bluish-purple. Healing may take many weeks and permanent scars may occur at the site of a sting.