The Blue Whale
The blue whale is the biggest mammal ever to exist on Earth, including all dinosaurs. Even newborn calves are bigger than most other animal species. Fully grown adults are roughly the length of three school buses parked end to end, typically measuring between 80 and 100 feet. The heart of a blue whale is enormous, weighing in at over 400 pounds. It will only beat twice per minute while diving for food.
The blue whale can weigh more than 150 tons. To give you some perspective, that's the same 30 adult African bush elephants weighing almost six tons each! That’s absolutely enormous!
Komodo Dragon
The biggest living lizard is the ferocious, forked-tongued Komodo dragon. Male Komodo dragons can reach a length of 10 feet and a weight of 200 pounds, while the maximum length for a female is 6 feet. These swift predators' have keen eyesight and a sense of smell that allow them to target water buffalo, deer, pigs, and, if you're in the wrong place at the wrong time, even people.
Komodo dragons are capable of running in short bursts at 13 mph. When threatened, they will even vomit the contents of their stomachs to lighten their load and run faster.
Goliath Frogs
The Goliath frog is an amphibian with attitude. It is the biggest frog ever recorded and can grow as large as an average house cat. At more than a foot in length and weighing over 7 pounds, these curious creatures are also champion jumpers. Goliath frogs can leap over ten feet forward. These enormous amphibians are silent, so you won't know they're there until they spring up in front of you.
Goliath frogs are nocturnal hunters who frequent river rocks. The diet of an adult goliath frog is similar to that of other frogs and includes insects, crustaceans, and fish.
Manta Ray
The size of a giant manta ray may just surprise you. Believe it or not, if you stood six fully grown men on each other's shoulders and measured from top to toe, that would equal the disc width of the giant manta ray. In fact, the average mature giant ray weighs up to 3,600 pounds. And while that's small compared to other sea creatures, we think it's worthy of our list.
Because the giant manta ray feeds on huge amounts of plankton, it has no need for teeth. But they have plates inside their mouths so that they can filter the water.
Giant Squid
The giant squid is one of the more mysterious creatures of the sea. Because humans rarely see them in their natural environment, most of what we know about them comes from studying giant squid washed up on beaches. The largest giant squid ever recorded was 59 feet long and weighed almost a ton. While they live on a diet of fish and shrimp, they have been known to attack small whales.
And can you believe their eyes are around 10 inches in diameter (about the size of a beachball), making them the biggest in the animal kingdom? That's pretty impressive!
The Reticulated Python and Green Anaconda
Reticulated pythons are the world's longest snakes, the longest ever recorded, measuring 32 feet, 9 inches. These versatile creatures are great swimmers; some have even been spotted at sea. They are so big and have such special abilities that they can overcome almost any obstacle. As ambush predators, reticulated pythons rely on their excellent sense of smell and quick reflexes to locate prey. But they are not the world's heaviest snake!
The green anaconda is the world's heaviest snake, weighing a whopping 550 pounds! They can grow to lengths of over 20 feet and widths of up to a foot.
Polar Bears
With a diet consisting primarily of seals, it's no wonder the polar bear is the largest land carnivore in the world. This magnificent beast can stand at an incredible 9 feet in length and weigh almost 1,800 pounds. When the temperature plummets along the coastal regions of their native Arctic, polar bears will wait patiently during the freezing weather for seals to surface at their breathing holes before pouncing.
Polar bears will also hunt by swimming beneath the ice since they are excellent swimmers. They paddle and propel themselves through the water with their large, slightly webbed front paws.
Elephant Seals
The elephant seal is by far the biggest pinniped, reaching lengths of over 20 feet and weighing up to 8,800 pounds. But despite their immense size, these massive creatures aren't named elephant seals because of their size. It's thanks to their inflated trunk-like snouts. There are two types of elephant seals, northern and southern. Southern elephant seals, found in the Antarctic, are by far the largest of all seals.
During the breeding season, male elephant seals will gather a harem of 40 to 50 females. Bloody battles are common among males as they try to establish dominance over each other.
Capybaras
The capybara reigns supreme among rodents. It is the planet's biggest living rodent and stands nearly 2 feet tall at the shoulders. Found on land or in water, the capybara dwarfs its cavy cousins and guinea pigs. These massive rodents are indigenous to South America, and are excellent swimmers, thanks to their somewhat webbed feet. Despite their size, they are quite gentle, sociable creatures that are frequently kept as pets.
Usually, there aren't more than ten capybaras in a group. However, during the dry season, a group can have up to 100 members, all led by a dominant male.
Whale Sharks
The whale shark, which may grow to be 40 feet in length, is the longest fish in the world. The massive fish tips the scales at over 20.6 tons, or approximately the same as two full-size school buses. These gentle giants are filter-feeders and are now recognized as the largest omnivores on Earth, surpassing even the largest Kodiak bears because of their voracious appetites for both krill and seaweed.
Native to the warm seas of the Atlantic and the Indo-Pacific, whale sharks are at risk of extinction because they are frequently trapped by fisheries or entangled in nets as bycatch.
The Japanese Spider Crab
Although there are large numbers of arthropods on Earth, only the Japanese spider crab can lay claim to the title of biggest arthropod species. The largest known Japanese spider crab measured 12.5 feet in length. But suppose you consider it unfair because all the length is in its legs. In that case, the world's largest arthropod is most likely the American lobster, with a considerably smaller size of 3.2 feet.
The spider crab can be found all around the world, although it is notably abundant in East Asia. Spider crab is prized for its refined flavor and high nutritional content.
Giant Isopods
Because they have no spine, giant isopods are classified as invertebrates. They live in the frigid depths of the Atlantic, Pacific, and Indian oceans and can reach a length of 30 inches, making them the biggest isopods known to science. They carry the abysmal gigantism gene, which causes their enormous size. They appear like common woodlice or pill bugs, but they are actually closely related to crabs and shrimp.
This enormous isopod protects itself from predators by curling into a ball and exposing its shell. You won't be bumping into them anytime soon; they live at depths of 7020 feet.
Giraffes
The Giraffe stands as the world's tallest land mammal. This long-necked, hoofed animal was once common in sub-Saharan Africa, where it could be found grazing in open woodlands. The Giraffe's neck has the same amount of bones as many other hoofed animals; they’re just longer in form. Since it takes a lot of food to sustain its massive frame, the Giraffe will consume more than 75 pounds of leaves daily.
Male giraffes will search widely in their pursuit of a suitable mate. But if they encounter another male competitor, they will bang heads and interlock their necks to assert dominance.
Great Dane
According to Guinness World Records, the largest dog ever recorded was a Great Dane from Otsego, Michigan, named Zeus. He was 3.6 feet tall at his shoulders. But according to Guinness World Records, when he stood on his hind legs, he was 7 feet, 4 inches tall, making him taller than most professional basketball players. Unfortunately, this magnificent 155-pound dog passed away at the age of 5 in 2014.
Great Danes are incredibly strong and graceful. Males may grow to be 32 inches tall and weigh 120 pounds, while females are slightly smaller but have a similar weight range.
Lion's Mane Jellyfish
Lion's mane jellyfish have two extremes. They can be relatively tiny, with a diameter of about 0.5 inches, or grow to tremendous sizes, with a diameter of 6.6 feet. But it doesn't stop there. Its tentacles can be up to 49 feet long, making it the world's largest jellyfish. Can you imagine that a lion's mane jellyfish, with its body and tentacles included, can grow longer than a blue whale?
In 2010, it was reported that a single lion's mane jellyfish stung between fifty and one hundred people swimming off the coast of New Hampshire. Their sting is very painful.
The Flying Fox Fruit Bat
With a wing span of up to 5.5 feet, the world's largest bat is simply awe-inspiring. They are widely known as the golden-capped fruit bat and the golden-crowned flying fox. Despite their size, these monsters only weigh approximately 2.6 pounds. This fruit bat is native to the Philippines but is at risk of extinction due to the destruction of their habitat and hunting. Being nocturnal, they forage at night.
These creatures prefer old, mature forests unoccupied by people as their habitat. As fig trees are the bats' primary food source, they also inhabit river corridors known as riparian zones.
The Eastern Gorilla
With a maximum height of 6.2 feet and a weight of about 450 pounds, the eastern gorilla easily wins the title of biggest primate.These gorillas can be found in the forested mountain regions of the Democratic Republic of the Congo, Rwanda, and Uganda. Less than 5,000 eastern gorillas remain in the wild, making them an endangered species. The eastern gorilla can live to between 35 and 50 years.
The eastern gorilla has powerful jaws and teeth to go along with its noticeably large head. They have thick, black fur covering their bodies, and they walk on their knuckles.
Queen Alexandra’s Birdwing Butterfly
Queen Alexandra's birdwing is the biggest living butterfly, with a wingspan of around one foot wide. While the species' yellow, green, black, and blue males have significantly shorter wingspans of 6.7 to 7.4 inches, the brown females of the species have an 11 to 12-inch wingspan. Unfortunately, the IUCN classifies this rare beautiful butterfly, which inhabits a 40-mile-long patch of coastal rainforest in Papua New Guinea, as endangered.
Predators seldom attack these wonderful creatures when fully grown due to their size and menacing appearance. While birds occasionally attack them, these stunning butterflies can successfully scare them away when confronted.
The Hippopotamus
The hippopotamus is the biggest semi-aquatic animal and the third largest kind of land mammal, reaching a length of up to 13 feet and a weight of up to 3.5 tons. Despite appearances, the hippopotamus is more closely linked to whales than any other animal group thanks to an ancestor they both shared in common some 54 million years ago. Anyone who thinks they're cute and cuddly couldn't be more wrong.
In Africa, hippos are among the deadliest animals, responsible for the deaths of 500 humans per year. When angered, a hippo can run 20 miles per hour in short bursts.
Chinese Giant Salamander
The Chinese Giant Salamander is the world's biggest salamander and amphibian, reaching lengths of up to 6 feet. With an impressive family tree dating back 170 million years, the Giant Salamanders are sometimes referred to as "living fossils" since they still resemble their prehistoric ancestors. But while they have lasted such an incredible amount of time, sadly, these cannibalistic ambush predators are now on the brink of extinction.
Sensors on the salamander's flat heads help them to find their prey thanks to shifts in water pressure, while flaring skin on its sides helps this mottled gray creature breathe.
The Galapagos Tortoise
The Galapagos Tortoise is the biggest of its kind. The largest specimen measured 4 feet and 5 inches in length and tipped the scales at 919 pounds. The average lifespan of these tortoises is well over a century, making them the oldest living vertebrates. The 152-year-old was the oldest tortoise ever documented. Tortoise shells may appear solid, but they are lighter than they look, thanks to their honeycomb-like structure.
While tortoises aren't the best swimmers, they made it to Galapagos about three million years ago from South America without drowning. The Spanish word "Galapagos" means "turtle" or "tortoise."
Giant Huntsman Spider
The leg span of the Giant Huntsman Spider, at up to 12 inches, makes it the biggest spider in the world. These quick spiders are well-known not just for their massive size but also for their remarkable method of capturing their prey. Their name comes from the fact that they hunt their food rather than catch it in a web. Australia, Africa, Asia, the Mediterranean, and the Americas are all Huntsman territories.
The legs of huntsman spiders are twisted in such a way that they stretch forward like a crab. And despite their massive size, they are actually rather peaceful and gentle.
The Cinereous Vulture
The cinereous vulture, sometimes called the black vulture, monk vulture, or Eurasian black vulture, is one of Earth's biggest birds of prey. This massive raptor may grow to reach almost 4 feet in length, have a 10-foot wingspan, and weigh 31 pounds. This brilliant bird builds its nests on cliffs and in tall trees and can fly as high as the upper troposphere thanks to its ability to absorb more oxygen.
The bill of a cinereous vulture is strong enough to rip through the hardest skins. Still, apart from the occasional tortoise it drops, it seldom kills the prey it devours.
The Tasmanian Giant Crab
The Tasmanian Giant Crab is the biggest and heaviest crab species, with a maximum weight of 30 pounds and a carapace width of up to 18 inches. The crab, which may be found throughout the southern coast of Australia, anywhere from New South Wales to Western Australia, is extremely slow-growing and has a long life span. Tasmanian giant crabs eat smaller, slower-moving creatures like gastropods, crustaceans, and starfish.
In the summer, they are found most frequently at a depth of 560 to 590 feet, while in the winter, they can be found at a depth of 620 to 1,310 feet.
The Ostrich
The common ostrich, at 9 feet in height and 350 pounds in weight, is the biggest and heaviest living bird. Although it cannot fly, this bird can reach speeds of up to 40 miles per hour because of its extraordinarily large and muscular legs. Although they eat mostly plant matter, ostriches may occasionally snack on insects. The ostrich has the biggest eye of any terrestrial mammal, measuring around 2 inches in diameter.
Ostriches have three stomachs and a long intestine to help them digest the food they swallow whole because they lack teeth. They swallow stones to help grind their food.
The African Bush Elephant
The African Bush Elephant is the biggest terrestrial mammal in the world, at up to 24 feet in length, 13 feet in height, and 11 tons in weight. Elephants, which may be found in Africa's savannas, are herbivores who require a daily diet of roughly 350 pounds of vegetation. The gestation period of this species is 22 months, which is the longest of any mammal. They will drink 50 gallons every day.
An African bush elephant's tusks can grow to be 8 feet long and weigh between 50 and 100 pounds, which is around the size of the average human.
The Saltwater Crocodile
The saltwater crocodile, the biggest reptile in the world, is a native of brackish and freshwater areas of Eastern India, Southeast Asia, and Northern Australia. Males typically weigh 92 pounds and are around 17 feet long. However, there have been accounts of crocodiles as large as 23 feet long and 4,400 pounds in India. The largest confirmed crocodile, however, was Lolong, a 20.24-foot-long, 2,370-pound, 50 year old crocodile.
Crocodiles are sociable creatures that form large groups. At the start of mating season, males become territorial and protect their river banks by lifting their huge heads and roaring at intruders.
The Goliath Beetle
The Goliath Beetle, found in the tropical parts of Africa, is the biggest in the world. It is speculated that these insects weigh more than any other. Their maximum weight as larvae is 3.5 ounces, and their maximum length as adults is 4.7 inches. These beetles are capable of lifting loads up to 850 times heavier than their own body weight. They have six legs and sharp claws for climbing.
A Y-shaped horn often protrudes from the top of the male's head. During mating and territorial disputes, they often use this horn as a weapon. They are black, white, and brown.
The Leatherback Sea Turtle
The Leatherback Sea Turtle is the biggest of all living turtles, reaching lengths of 7 feet and weighing more than 2,000 pounds, making it the fourth-heaviest reptile behind three crocodilians. The leatherback, which dates back more than 100 million years, is critically endangered today despite having formerly been found in every ocean on Earth save the Arctic and Antarctic. They are the only sea turtles without a hard shell.
The leatherback sea turtle stands out because of its ability to control its internal temperature. This will be useful when they are tens of thousands of feet below the surface.
The Giant Forest Scorpion
The giant forest scorpion, at a staggering 9.1 inches in length and roughly 2 ounces in weight, is the biggest scorpion in the world. These monsters, which can be either black or a darker brown, can be found in the jungles of Asia, especially in India and Sri Lanka, and feed on various insects, lizards, reptiles, and even other scorpions. Their venom is mild, and they are not aggressive.
Their enormous pincers are used to capture prey during hunts, and then that animal is torn to pieces. Giant forest scorpions only interact with one another during the mating process.
The Giant Clam
The maximum size of a giant clam is roughly between 4 and 5 feet long, and you will find them primarily in the South Pacific and Indian Oceans. Yellow, green, iridescent blue and purple are just some of the hues that may be found on the exposed mantle of a giant clam. It consumes zooplankton and microscopic marine plants and can live for a century or more if protected.
This mollusk attaches to a coral reef and lives there for the remainder of its life. The algae in this clam's system are what give its mantle its vibrant colors.
The Red Kangaroo
The red kangaroo is not only the national symbol of Australia but also the biggest kangaroo species on the planet. They can be found across much of Australia's interior and parts of the northwestern coast.The red kangaroo is a strong and agile animal with a tremendous jump of several feet. The red can utilize its tail as a footing when kicking, making the kick more powerful when necessary.
Males often pick fights during mating season solely to prove their group dominance. The largest kangaroo ever recorded was 8 feet long, standing 6 feet tall. What a marvelous marsupial!
Indian Rhinoceros
The Indian Rhinoceros, or Greater One-horned Rhinoceros, is an impressive creature recognized for its single black horn and armor-like skin. These rhinos reside in the northern part of the Indian subcontinent, primarily in India and Nepal. They are one of the largest species of rhinos, with males weighing up to 2,200 kilograms. Despite their enormous size, they are known for their relatively docile behavior unless threatened. Once ranging across the entire northern part of the Indian subcontinent, habitat loss and poaching have significantly reduced their numbers and distribution.
Today, efforts towards conservation have led to a gradual increase in their population. However, the Indian Rhinoceros is still considered a vulnerable species, due to ongoing threats, especially from poaching for their horns. Increased protection and preservation of their habitats remain crucial for their survival.
Emperor Penguin
Emperor Penguins are the tallest and heaviest of all living penguin species. Native to Antarctica, these fascinating birds are incredibly adapted to life in extreme cold. Adult emperors can stand up to 130 cm (about 4.2 feet) tall and weigh as much as 45 kg (about 99 pounds). Renowned for their striking black and white plumage with areas of yellow and orange around their necks, Emperor Penguins are perhaps best known for their extraordinary parenting skills in the harshest climate on Earth.
In the extreme Antarctic winter, male Emperor Penguins incubate their single egg for two months without eating, while females forage at sea. This incredible display of parental care and resilience in the face of harsh conditions is a testament to the adaptability of life on our planet.
Dalmatian Pelican
The Dalmatian Pelican is one of the world's largest flying bird species, standing up to 6 feet tall and boasting a wingspan that can exceed 11 feet. This impressive bird is predominantly greyish-white, with an elegant crest of feathers on the back of its head during breeding season. They inhabit a variety of water bodies, including freshwater lakes, deltas, and estuaries across Southeastern Europe to India and China. They are expert fishers, dipping their large, pouched bills to scoop up their prey.
Unfortunately, the Dalmatian Pelican is classified as 'Near Threatened' on the IUCN Red List of Threatened Species. The primary threats to its survival include habitat loss, disturbance, pollution, and competition with fisheries. Conservation efforts are necessary to ensure this magnificent bird's survival.
Goliath Birdeater
The Goliath Birdeater is a species of tarantula and is often considered the world's heaviest spider. Native to the rainforests of South America, it can reach a leg span of up to 11 inches and can weigh up to 6 ounces. Although its name suggests otherwise, the Goliath Birdeater's diet primarily consists of insects and small amphibians. Despite their fearsome appearance, these tarantulas are not particularly dangerous to humans, with their venom causing only mild discomfort.
Despite their formidable size, Goliath Birdeaters lead mostly solitary lives and come out primarily at night to hunt. Females can live up to 15-25 years, significantly longer than their male counterparts who live only 3-6 years, typically.
Beluga Sturgeon
The Beluga Sturgeon is an ancient species of fish that is native to the Caspian and Black Sea basins. Known for their massive size, they can grow up to 20 feet long and weigh over a ton, making them one of the largest freshwater fish. The Beluga Sturgeon is famous for its roe, or eggs, which are processed into the highly prized beluga caviar. This has led to overfishing, causing a serious decline in their population over the last few centuries.
Today, the Beluga Sturgeon is critically endangered. The demand for its caviar, coupled with habitat loss due to dam construction and pollution, has significantly reduced their numbers. Conservation efforts, including stricter fishing regulations and captive breeding programs, are vital for the survival of this unique species.
Kori Bustard
The Kori Bustard is a large bird native to Africa, renowned as one of the heaviest flying birds in the world. Adult males can weigh up to 19 kg (42 lbs) and stand over 120 cm (4 ft) tall. They have a predominantly gray and brown plumage that provides perfect camouflage against the savannah grasslands they inhabit. Kori Bustards are omnivorous, their diet is diverse including small mammals, birds, reptiles, insects, seeds, and berries.
Despite their impressive size, Kori Bustards are mostly silent and tend to be solitary or found in small groups. Their population is declining due to hunting and habitat loss. They are currently classified as "Near Threatened" by the International Union for Conservation of Nature (IUCN).
African Buffalo
The African Buffalo, also known as the Cape Buffalo, is a powerful herbivore native to Africa. Known for its large size, the African Buffalo can weigh up to 1,000 kilograms and stand nearly 1.7 meters tall at the shoulder. Its most distinctive feature is its set of heavy, curved horns which are used for defense. African Buffaloes have a strong herd instinct and their groups can number in the hundreds.
Unfortunately, the African Buffalo is threatened by habitat loss and diseases such as bovine tuberculosis and corridor disease. Despite these threats, it remains one of the most successful grazers in Africa, thanks to its adaptability to different habitats and strong herd defense mechanisms.
Moose
The Moose is the largest species in the deer family, known for its distinctive broad, flat antlers and impressive size. Native to the northern regions of North America, Europe, and Asia, moose can stand over 2 meters at the shoulder and weigh up to 700 kilograms. Their diet primarily consists of terrestrial and aquatic vegetation. Moose are excellent swimmers and are known to wade into water bodies to feed on aquatic plants.
Moose are solitary animals, unlike many other deer species that form herds. They face threats from predators such as wolves and bears, and from road collisions in areas where their habitats intersect with human settlements. Conservation efforts focus on managing hunting and maintaining the integrity of their habitats.
Atlas Moth
The Atlas Moth, native to the forests of Asia, is one of the largest lepidopterans in the world, boasting an impressive wingspan that can exceed 24 cm (9.4 in) and a wing surface area of about 400 square cm (62 square in). Its name derives from the intricate, map-like patterns on its wings. Interestingly, adult Atlas Moths do not have a mouth and cannot eat; they survive on fat reserves they accumulated during their larval stage.
Atlas Moths are a marvel of nature not only due to their size, but also because of their unique life cycle. They live for only about one to two weeks as adults, during which their sole purpose is to find a mate and reproduce. Their short lifespan is a stark contrast to their majestic appearance.
Perentie
The Perentie, native to Australia, is the largest monitor lizard or goanna in the country, and the fourth-largest living lizard on earth. They can reach lengths of up to 2.5 meters (8.2 ft). They inhabit arid areas and have adapted to the harsh desert environment. They are skilled climbers and swimmers but are most often found on the ground, hunting for prey. Perenties are carnivorous, feeding on a variety of animals including insects, birds, and small mammals.
The Perentie's cultural significance extends into indigenous Australian lore, where it is often featured in mythology and rock art. Despite its intimidating size, it generally avoids human interaction and poses no significant threat unless provoked.
Bengal Tiger
The Bengal Tiger, native to the Indian subcontinent, is one of the largest and most iconic species of big cats. Known for their striking orange coat with black stripes, adult males can weigh up to 258 kg (569 lbs) and measure up to 3 meters (10 ft) in length. These solitary predators primarily feed on large mammals such as deer and wild boar. Bengal Tigers play a crucial role in the ecosystems they inhabit, controlling prey populations and maintaining balance.
Regrettably, Bengal Tigers are classified as endangered due to threats like habitat loss, human conflict, and especially poaching for their skins and body parts. Conservation efforts are ongoing to protect these majestic creatures and their habitats to ensure their survival for generations to come.