Land or Water?

Nature is full of amazing animals with fascinating abilities. These abilities help them survive in their respective habitats. When their landscapes change, animals can adapt to fit the new conditions. An example of these adaptations is the existence of amphibious creatures. Amphibious animals can maneuver efficiently on land as well as in the water. Let’s take a look at a few amphibious animals.

Giant river otters are the largest otters in the world, and the species is one of the largest members of the weasel family—spanning up to six feet long and weighing up to 75 pounds! They reside in South America, solely in the Amazon, Orinoco, and La Plata rivers. As carnivores, their main diet depends on fish such as piranhas and catfish. Other meals include crustaceans, snakes, and other river animals. Living in extended families, they establish and defend a territory like a pack of wolves would, earning them the nickname “the wolves of the river.”

Fun Fact: Giant otters snort snot when curious or alarmed!

Otters are social creatures, so they can be playful at times. But make no mistake: these animals can be extremely tough when they need to be. As a pack, they can even fend off a bull shark when these sharks swim hundreds of miles upriver. With webbed feet and water-repellent fur, the otters are skilled swimmers, propelling themselves with an up-and-down motion and steering with their tail. On land, however, their feet have retractable claws that prevent the otter from slipping while running. Unfortunately, giant river otters are endangered and their population is gradually decreasing due to hunting and poaching (hunting or fishing illegally).

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Another amphibious mammal is the capybara, the largest rodent in the world. Although closely related to guinea pigs, their bodies more accurately resemble those of pigs. At 4.6 feet long and up to 2 feet at the shoulders, their weight can range from 77 to 143 pounds. Found primarily in South America in herds of up to 40 members, these rodents have adapted to life on land and in the water.

Fun Fact: Capybaras eat their own poo in the morning to take in extra protein from their previous meal!

Traction pads on the bottom of their feet prevent them from slipping when running, especially at speeds almost as fast as a young horse! They are also excellent swimmers due to their webbed feet and special fat reserves that aid in maintaining a neutrally buoyant position. Their eyes, ears, and nostrils are positioned towards the top of their blocky heads so that they are out of the water when the capybaras are swimming on the surface; this allows them to stay alert in case there are any predators, of which they have a lot. They can also dive underwater if needed. Their diet consists of a variety of plants, chiefly grasses and aquatic plants. Eating these plants actually wears their teeth down, curbing their teeth’s continuous growth.

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Mammals are not the only ones that can be amphibious: there are amphibious reptiles too. The green anaconda is one example. These snakes are known for being the largest snakes in the world in terms of weight (the longest being its cousin, the reticulated python), weighing over 500 pounds! They can grow up to 29 feet long and over a foot wide. Although they can maneuver on land and in the trees, they move more efficiently in the water. When hunting, they remain motionless with their eyes and nostrils, which are located on top of their heads, above the surface of the water.

Fun Fact: Female anacondas actually grow bigger than male anacondas!

This concealed position allows them to ambush (which means to surprise by attacking from a hidden place) their prey then constrict it using thousands of body muscles. Once the prey’s heart stops beating, the anaconda swallows it whole using stretchy ligaments in their mouth and backward-pointing teeth in the middle of their upper jaw that help the snake get its head up and over the prey. Swallowing prey, especially large creatures such as jaguars, can take hours, and in order to breathe, the anaconda’s windpipe is forced out of its mouth, almost like a snorkel. The meal takes over a week to digest, but the snake doesn’t need to eat for another few weeks or even months. After 7 months of pregnancy and fasting, female anacondas give live birth to 20-30 baby snakes that already have survival instincts. The mother then feasts on undeveloped eggs and stillborn babies to regain her strength.

Amphibious animals are only one instance of nature’s ability to adapt. Evolution is necessary for their survival, for their habitats can change. There is still so much unknown about certain biomes like the Amazon, and scientists are still discovering new species in the rainforest. As a matter of fact, nature can provide much inspiration for technology: evolution has turned the natural world into a living lab. I hope you learned something new today! Until next time!