Slowest animals on Earth
At 60 mph, the cheetahs are fast, but watch these other speedy creatures fly! The basilisk lizard runs so fast that it can walk on water and the ostrich is just about the fastest animal on two legs. But is cheetahs the fastest animal on earth? And while the ostrich will never fly, it's just about the fastest thing on two legs. Right now, forget fastest. What about the slowest animals?
This countdown will reveal the Most Extreme of the slowest animals on earth!
1. Three-toed Sloth
The three-toed sloths are tree-living insectivores from South and Central America. There are four living species of three-toed sloths. These are the Brown-throated Sloth, the Maned Sloth, the Pale-throated Sloth, and the Pygmy Three-toed Sloth. Sloth’s are so slow they can be moving and algae grow on them. A sloth’s top speed is .003 miles per hour.
Three-toed sloths are about the size of a small dog or a large cat, with the head and body having a combined length of around 45 centimeters (18 in), and the animal having a weight of 3.5–4.5 kilograms (8–10 lb). Unlike the two-toed sloths, they also have a short tail of 6–7 centimeters (2–3 in), and they have three clawed toes on each limb.
They are frequently referred to as three-toed sloths, however all sloths have 3 toes, the difference is found in the number of fingers; meaning they are now more appropriately referred to as three-fingered sloths.
The three-toed sloth, unlike most other mammals, does not fully maintain a constant body temperature, and this limits it to warm environments. Members of this species tend to live around 25 to 30 years, reaching sexual maturation at 2 years of age.
Females give birth to a single young after a gestation period of around six months. They are weaned at about 9 months of age, at which point, the mother leaves her home territory to her offspring and moves elsewhere. Adults are solitary, and mark their territories using anal scent glands and dung middens.
2. Starfish
There are about 1,800 living species of starfish that occur in all the world's oceans, including the Atlantic, Pacific, Indian as well as in the Arctic and the Southern Ocean (i.e., Antarctic) regions. Starfish occur across a broad depth range from the intertidal to abyssal depths (>6000 m). Star fish’s top speed is .06 miles per hour. They can’t really move on their own but they just go with the current of the ocean.
Starfish are among the most familiar of marine animals and possess a number of widely known traits, such as regeneration and feeding on mussels. Starfish possess a wide diversity of body forms and feeding methods.
The extent that Asteroidea can regenerate varies with individual species. Broadly speaking, starfish are opportunistic feeders, with several species having specialized feeding behavior, including suspension feeding and specialized predation on specific prey.
Most starfish typically have five rays or arms, which radiate from a central disk. However, several species frequently have six or more arms. The body surface of sea stars often has several structures that comprise the basic anatomy of the animal and can sometimes assist in its identification.
3. Garden Snail
Helix aspersa, known by the common name garden snail, is a species of land snail, a pulmonate gastropod that is one of the best-known of all terrestrial molluscs. The shells must slow them down otherwise they’d be considered slugs. Interesting fact: snails can sleep for three years.
The adult bears a hard, thin calcareous shell 25–40 mm in diameter and 25–35 mm high, with four or five whorls. The shell is somewhat variable in color and shade but is generally dark brown or chestnut with yellow stripes, flecks, or streaks.
The body is soft and slimy, brownish-grey, and is retracted entirely into the shell when the animal is inactive or threatened. During dry and cold weather, the aperture of the shell is sealed with a thin membrane of dried mucus which is known as an epiphragm, which helps the snail retain moisture. The resultant quiescent periods are known as aestivation and hibernation respectively.
When hibernating, Garden Snail avoids ice formation by altering the osmotic components of its blood), and can survive temperatures as low as -5°C. During aestivation, the mantle collar has the unique ability to change its permeability to water.
In combination with an osmoregulatory mechanism similar to that seen during hibernation this allows Garden snail to survive several months of aestivation.
4. Giant tortoise
Giant tortoises are characteristic reptiles of certain tropical islands. Often reaching enormous size—they can weigh as much as 300 kg (660 lbs) and can grow to be 1.3 m (4 ft) long—they live, or lived (some species are recently extinct), in the Seychelles, the Mascarenes and the Galapagos. Giant Tortoise could be used as a noun for a slow person. So they must be slow. On the plus side, they can live to be 150 years old.
Today, the world's largest population inhabits Aldabra Atoll in Seychelles, where there are approximately 150,000 individuals. Although appearing similar, the tortoises represent separate branches of evolution. The Seychelles and Mascarenes tortoises derive from nearby Madagascar, while the Galapagos tortoises came from nearby Ecuador.
Prior to the arrival of Homo sapiens, giant tortoises occurred in non-island locales as well. Between 200,000 to 10,000 years ago, tortoises on the mainland of Asia, Indonesia, Madagascar, North and South America, and even the island of Malta became extinct.
These animals belong to an ancient group of reptiles, appearing about 250 million years ago. In the Upper Cretaceous, 70 or 80 million years ago some already became gigantic. About 1 million years ago tortoises reached the Galapagos Islands.
Since 100,000 years ago most of the gigantic species began to disappear. Only 250 years ago there were at least 20 species and subspecies in islands of the Indian Ocean and 14 or 15 subspecies in the Galapagos Islands.
5. Koala Bear
The koala is an arboreal herbivorous marsupial native to Australia, and the only extant representative of the family Phascolarctidae. A little off topic but interesting fact about these cute bears. They are an endangered species because of the food they eat makes them high, so they fall out of the tree’s and die. No joke.
The koala is found in coastal regions of eastern and southern Australia, from Adelaide to the southern part of Cape York Peninsula. Populations also extend for considerable distances inland in regions with enough moisture to support suitable woodlands.
The koalas of South Australia were largely exterminated during the early part of the 20th century, but the state has since been repopulated with Victorian stock. The koala is not found in Tasmania or Western Australia.
The koala is broadly similar in appearance to the wombat (its closest living relative), but has a thicker coat, much larger ears, and longer limbs. The koala has large, sharp claws to assist with climbing tree trunks. Weight varies from about 14 kg (31 lb) for a large southern male, to about 5 kg (11 lb) for a small northern female.
It is generally a silent animal, but males have a very loud advertising call that can be heard from almost a kilometer away during the breeding season. Females glean clues regarding a male's suitability as a mate from these calls, showing a preference for larger males.
When under stress, koalas may issue a loud cry, which has been reported as similar to that of a human baby. There is little reliable information about the lifespan of the koala, but in captivity they have been observed to reach the age of 18 years.
6. Slug
Slugs, like all other gastropods, undergo torsion (a 180º twisting of the internal organs) during development. Internally, slug anatomy clearly shows the effects of this rotation, but externally the bodies of slugs appear rather symmetrical, except for the positioning of the pneumostome, which is on one side of the animal, normally the right hand side.
The soft, slimy bodies of slugs are prone to desiccation, so land-living slugs are confined to moist environments and must retreat to damp hiding places when the weather is dry. Slugs never reach a speed of 0.2 miles per hour. In fact the fastest slug ever recorded was .19 miles per hour.
Slugs' bodies are made up mostly of water, and without a full-sized shell, their soft tissues are prone to desiccation. They must generate protective mucus to survive. Many species are most active just after rain because of the moist ground.
In drier conditions, they hide in damp places such as under tree bark, fallen logs, rocks, and man-made structures, such as planters, to help retain body moisture.
Slugs produce two types of mucus: one which is thin and watery, and another which is thick and sticky. Both kinds of mucus are hygroscopic. The thin mucus spreads from the foot's centre to its edges, whereas the thick mucus spreads from front to back. Slugs also produce thick mucus which coats the whole body of the animal.
7. Seahorse
Seahorses compose the fish genus Hippocampus within the family Syngnathidae, in order Syngnathiformes. Syngnathidae also includes the pipefishes. "Hippocampus" comes from the Ancient Greek hippos meaning "horse" and kampos meaning “sea monster”.
Top speed of Seahorse? 5 miles per an hour! And that is when they are booking it. Seahorses even look like the most non sealant swimmers in the sea.
There are nearly 50 species of seahorse. They are mainly found in shallow tropical and temperate waters throughout the world. They prefer to live in sheltered areas such as sea grass beds, coral reefs, or mangroves.
Seahorses are named for their equine profile. Although they are bony fish, they do not have scales, but rather a thin skin stretched over a series of bony plates arranged in rings throughout their body. Each species has a distinct number of rings.
Seahorses swim upright, another characteristic that is not shared by their close pipefish relatives, which swim horizontally. Seahorses have a coronet on their head, which is distinct to each individual, much like a human fingerprint.
They swim very poorly by using a dorsal fin, which they rapidly flutter and pectoral fins, located behind their eyes, which they use to steer. Seahorses have no caudal fin. Since they are poor swimmers, they are most likely to be found resting, with their prehensile tails wound around a stationary object.
They have long snouts, which they use to suck up food, and eyes that can move independently of each other, much like a chameleon. Seahorses eat small shrimp, tiny fish, crustaceans and plankton.
8. Nematodes
The nematodes or roundworms are the most diverse phylum of Body cavity, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic.
It has been estimated that the total number of nematode species might be approximately 1,000,000. Unlike cnidarians or flatworms, roundworms have a digestive system that is like a tube with openings at both ends.
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Colorized electron micrograph of soybean cyst nematode (Heterodera sp.) and egg |
Nematodes have successfully adapted to nearly every ecosystem from marine to fresh water, from the Polar Regions to the tropics, as well as the highest to the lowest of elevations. They are ubiquitous in freshwater, marine, and terrestrial environments, where they often outnumber other animals in both individual and species counts, and are found in locations as diverse as mountains, deserts, oceanic trenches, and within the earth's lithosphere.
They represent, for example, 90% of all life forms on the ocean floor. Their many parasitic forms include pathogens in most plants and animals (including humans). Some nematodes can undergo Cryptobiosis.
Nematodes are a slender type of worm, typically less than 2.5 millimeters (0.10 in) long. The smallest nematodes are microscopic, while free-living species can reach as much as 5 centimeters (2.0 in) and some parasitic species are larger still. The body is often ornamented with ridges, rings, warts, bristles or other distinctive structures.
The head of a nematode is relatively distinct. Whereas the rest of the body is bilaterally symmetrical, the head is radially symmetrical, with sensory bristles and, in many cases, solid head-shields radiating outwards around the mouth. The mouth has either three or six lips, which often bear a series of teeth on their inner edge. An adhesive caudal gland is often found at the tip of the tail.
9. Gila monster
The Gila monster is a species of venomous lizard native to the southwestern United States and northwestern Mexican state of Sonora & Australia. A heavy slow-moving lizard, up to 60 cm (2.0 ft) long, who lives in deserts, slugs around the sand and mainly stays where it is to conserve it’s energy.
It is estimated that the Gila monster spends 95% of its time underground in mammal burrows or rocky shelters. It is active in the morning during the dry season (spring and early summer); later in the summer, it may be active on warm nights or after a thunderstorm. On the surface, it maintains a body temperature of about 30 °C (86 °F). Gila monsters are slow in terms of sprinting ability, but they have relatively high endurance and maximal aerobic capacity for a lizard.
The Gila monster feeds primarily on bird and reptile eggs, and occasionally upon small birds, mammals, frogs, lizards, insects, and carrion. The Gila monster eats infrequently (only five to ten times a year in the wild), but when it does feed, it may eat up to one-third of its body mass.
It uses its extremely acute sense of smell to locate prey, especially eggs. Its sense of smell is so keen that it can locate and dig up chicken eggs buried 15 centimeters (5.9 in) deep and accurately follow a trail made by rolling an egg.
The Gila monster venom is produced in modified salivary glands in the Gila monsters lower jaw, unlike snakes, whose venom is produced in the upper jaw.
The Gila monster lacks the musculature to forcibly inject the venom; instead, the venom is propelled from the gland to the tooth by chewing. Capillary action brings the venom out of the tooth and into the victim.
10. Manatee
Manatees are large, fully aquatic, mostly herbivorous marine mammals sometimes known as sea cows. There are three accepted living species of Trichechidae, representing three of the four living species in the order Sirenia: the Amazonian manatee, the West Indian manatee, and the West African manatee.
They measure up to 13 feet (4.0 m) long, weigh as much as 1,300 pounds (590 kg), and have paddle-like flippers. They have flippers but rarely use them. They stay in the shallow water and just float around very rarely reaching a speed over five miles an hour.
Manatees have a mass of 400 to 550 kilograms (880 to 1,200 lb), and mean length of 2.8 to 3 meters (9.2 to 9.8 ft), with maximums of 3.6 meters (12 ft) and 1,775 kilograms (3,910 lb) seen (the females tend to be larger and heavier). When born, baby manatees have an average mass of 30 kilograms (66 lb). They have a large flexible prehensile upper lip.
They use the lip to gather food and eat, as well as using it for social interactions and communications. Manatees have shorter snouts than their fellow sirenians, the dugongs. Their small, widely-spaced eyes have eyelids that close in a circular manner. The adults have no incisor or canine teeth, just a set of cheek teeth, which are not clearly differentiated into molars and premolars.
Uniquely among mammals, these teeth are continuously replaced throughout life, with new teeth growing at the rear as older teeth fallout from farther forward in the mouth. At any given time, a manatee typically has no more than six teeth in each jaw of its mouth. Its tail is paddle-shaped, and is the clearest visible difference between manatees and dugongs; a dugong tail is fluked, similar in shape to that of a whale.
Like horses, they have a simple stomach, but a large cecum, in which they can digest tough plant matter. In general, their intestines have typical length about 45 meters, which are unusually long for animals of their size. Article & Image Source: wikipedia, web.
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