What is the secret of the Longest Living Animals on Earth?
Humans have a short lifespan on Eaarth as compared to animals. According to World Health Organization, the average life expectancy of humans is 70 years. Some creatures on the earth are immortal, and others can live for thousands of years. Scientists are attempting to reveal why some animals live so long. The oldest human was only 122 years old (cue the Greenland shark’s laughter!).
But how do these long-lived animals manage to live for centuries? Scientists believe it is related to the animals’ metabolism, size, and habitat. Larger animals have slower metabolism. Animals that live in frigid, cold environments have a slower metabolism. Greenland sharks can survive in the Arctic for centuries because of the cold water. Metabolic rate is believed to be inversely proportional to maximum lifespan, which means that fast-living species die young, whereas slow-living species live slower and longer.
Here is a list of some of the longest-living animals:
1. Rougheye rockfish
Its scientific name is Sebastes aleutianus. According to the Washington Department of Fish and Wildlife, they are among the longest-living fish, with a maximum lifespan of at least 205 years. These fish are pink or brownish. Their natural habitat is in coastal waters stretching from California to Japan.
Rougheye rockfish typically live at depths ranging from 500 to 1,500 feet. They live near the seafloor, in caves and crevices. According to the Committee on the Status of Endangered Wildlife in Canada, they can grow to be 38 inches (97 centimeters) long and eat other animals such as shrimp and smaller fish (opens in new tab), Rockfish grow slowly, mature late, and live a long time.
Unfortunately, this makes them particularly vulnerable to overfishing. Rockfish grow slowly, mature late, and live a long time. Unfortunately, this makes them particularly susceptible to overfishing.
2. Tuatara
It is the longest-lived vertebrate on Earth. It has inhabited the planet for over 200 million years. Its scientific name is Sphenodontia. The tuatara lives on New Zealand’s small islands and grows slowly. This small animal is only active at night. The lizard can live up to 60 years, but in captivity it can live for over 100 years, reaching a length of 76 cm.
Furthermore, the animal represents the beak-headed order, and it is the only living representative of this order today. The reptile resembles a large iguana on the outside. The lizard is distinguished by the presence of a “third eye” on the crown, which is overgrown with scales in adults.
Tuataras reach sexual maturity between the ages of 10 and 20 years and continue to grow until they are 35 to 40 years old.
3. Hydra
Hydra is small invertebrates with soft bodies. It resembles jellyfish and, like T. dohrnii, can live indefinitely. These invertebrates are largely composed of stem cells, which regenerate continuously through duplication or cloning, they do not deteriorate as they age. They do die in natural conditions due to threats such as predators and disease, but without these external threats, they could continue to regenerate indefinitely.
“They don’t seem to age, so they could be immortal,” said Daniel Martnez, a biology professor at Pomona College in Claremont, California, who discovered the hydra’s lack of aging.
4. Greenland Shark
Somniosus microcephalus lives deep in the Arctic and North Atlantic oceans. It belongs to the somnios family. Sharks grow about 0.5 to 1 cm per year and can reach lengths of up to 24 feet. Only shark that can withstand Arctic temperatures year round, ranging from 7 to -2 degrees.
It eats a variety of other animals, including fish and marine mammals like seals. This is unusual because most sharks are thermophilic. The animal can live for 100-200 years, which is the longest lifespan for sharks.
The oldest shark in that study was estimated to be around 392 years old, and the researchers speculated that the sharks could have been up to 512 years old, as previously reported by Live Science.
5. JellyFish
Scientifically it is known as Turritopsis dohrnii. It is an immortal jellyfish because it has the potential to live indefinitely. Jellyfish begin life as larvae before settling on the seafloor and developing into polyps. These polyps then give rise to free-swimming medusas, also known as jellyfish.
According to the American Museum of Natural History, mature T. dohrnii can turn back into polyps if they are physically damaged or starved and then return to their jellyfish state.
It is the only immortal creature on Earth and has no brain or heart. It lives in tropical waters. Jellyfish are native to the Mediterranean Sea. It can repeat this feat of reversing its life cycle multiple times and thus may never die of old age under the right conditions. T. dohrnii are small — less than 0.2 inch (4.5 millimeters) across — and are eaten by other animals, such as fish, or die in other ways, preventing them from achieving immortality.
6. Bowhead Whale
The Bowhead whale is known as Balaena mysticetus. The longest-living mammal lives in the colder waters of the north Atlantic and north Pacific oceans. Bowhead whales can break through sea ice up to seven inches thick due to their large skulls and muscular bodies. Adult bowheads are completely black, except for the front region of the lower jaw, which is white and noticeably upturned.
According to the National Oceanic and Atmospheric Administration, they can comfortably live for more than 100 years and may live for more than 200 years (NOAA).
Bowhead whales have a gene called ERCC1 in their bodies that keeps repairing the body’s damaged DNA. As a result, these fish are free of deadly diseases such as cancer, neurodegenerative disease, cardiovascular disease, and metabolic disease.
Furthermore, a section of another gene called PCNA has been duplicated. This gene is involved in cell growth and repair, and its duplication may slow the aging process. They can reach a height of 60 feet (18.3 meters), weigh 200,000 pounds (91 tonnes), and consume approximately 220,000 pounds (100 tonnes) of food per year.
7. Giant Galapagos Tortoise
Tortoises are well-known for their longevity. A 190-year-old Seychelles giant tortoise is the oldest living land animal. It is also known as Aldabrachelys gigantic hololissa. The tortoise lives on the South Atlantic Ocean island of St. Helena. In 1882, People brought him there from Seychelles.
Adwaita, a male tortoise, died in 2006 at the age of 255 at Kolkata’s Alipore Zoological Gardens. He ate wheat bran, carrots, lettuce, soaked gram (chickpea), bread, grass, and salt. This male tortoise of the Algebra species, weighing up to 250 kg, is said to have been given to Lord Clive, the founder of the British Empire in India. These tortoises can live for up to 150-250 years on average.
8. Koi Fish
Koi (Cyprinus rubrofuscus) is a tamed ornamental variety of the common carp. They have an average lifespan of 40 years, but the oldest known koi lived to be more than 200 years old.
Koi are native to the Caspian Sea’s fresh waters and can grow to be three feet long. There are wild populations in North America, South America, Africa, Europe, and Asia. Initially, they were eaten but then they were kept at home. Koi are commonly found in man-made rock pools and decorative ponds.
9. Red Sea Urchin
Strongylocentrotus franciscanus is a spine-covered small round invertebrate. They live in shallow coastal waters off the coasts of North America, from California to Alaska, and feed on marine plants. These creatures also live near rocky areas with low tides of up to 90 meters. They are also seen crawling along the ocean floor using their spines. It stays primarily from the low-tide line down to 300 feet and avoids extremely wavy areas.
Red sea urchins grew quickly and had short life spans of up to ten years, but as scientists studied the species more closely, they discovered that these urchins continue to grow slowly. If they can avoid predators, disease, and fishers, they can live for centuries.
Red sea urchins found off the coasts of Washington and Alaska are likely to live for more than a century, and the longest-living individuals in British Columbia, Canada, maybe around 200 years old.
10. Longfin Eel
Longfin eels can live up to 60 years, but the longest recorded lifespan was 106! They are indigenous to New Zealand and Australia. These eels spend the majority of their lives hiding in freshwater streams before migrating to the Pacific Ocean to breed. They only spawn once in their lifetime and then die. They are slow-growing animals, growing only 1-2cm per year, but females can grow to be 73-156 cm long.
11. Freshwater pearl mussels
Margaritifera margaritifera are bivalves that filter food particles from water. They are found in Europe and North America, primarily in rivers and streams. The oldest freshwater pearl mussel found was 280 years old. Because of their low metabolism, these invertebrates have long life spans.
The freshwater pearl mussel begins life as a tiny larva, measuring about 0.6 to 0.7 millimeters in length, which is expelled into the water by an adult mussel along with one to four million other larvae.
Freshwater mussels are excellent bioindicators because they live for a long time and are sensitive to environmental changes. It is a threatened species. Their population is declining due to a variety of human-caused factors, including liver damage and changes.
12. Geoduck clam
It is a species of very large saltwater clam in the family Hiatellidae. These colossal saltwater clams have been observed to live for over 165 years. Geoducks (Panopea generosa) grow at a rapid rate during their first four years of life, gaining more than an inch per year on average. They are distinguished by their long “necks,” or siphons, which can reach lengths of more than three feet, while the shell is typically no longer than eight inches.
Geoducks are indigenous to the Pacific Northwest, stretching from California to Alaska.
13. Tubeworm
Lamellibrachia luymesi are colorful deep-sea tubeworms. Invertebrates that live on the ocean floor are known as tube worms. Bacteria in their tubes produce sugars from chemicals, that they consume. Some tube worms live near hydrothermal vents, but the longest-living species live in colder, more stable environments known as cold seeps, where chemicals spew from seafloor cracks or fissures.
The tube worm resembles a giant plastic straw with a delicate pink flower at the end when it extends its petal-like plume – a gill-like organ for gas exchange – out of the top of its tube. They can grow to be more than 1.5 meters long and feed by forming a symbiotic relationship with bacteria that thrive in leaks.
According to a 2017 study published in the journal The Science of Nature, Escarpia laminate, is a cold-seep species of tube worm found in the Gulf of Mexico. It can live for up to 200 years, with some specimens living for more than 300 years. Tube worms have a slow metabolism and few natural predators, which has allowed them to evolve with such long life spans.
14. Ocean quahog clams
The North Atlantic Ocean is home to ocean quahog clams (Arctica islandica). This saltwater species can live even longer than the freshwater pearl mussel. According to the National Museum Wales in the United Kingdom, one ocean quahog clam discovered off the coast of Iceland in 2006 was 507 years old.
The Ocean Quahog has a slower metabolism in the colder waters surrounding Iceland, so it grows slowly and may even live longer than 507. The filter feeders burrow into the ocean floor and feed on microscopic algae.
15. Black Coral
Corals appear to be colorful underwater rocks and plants, but they are the exoskeletons of invertebrates known as polyps. These polyps continually multiply and replace themselves by producing a genetically identical copy, causing the coral exoskeleton structure to grow larger and larger over time.
Corals are thus made up of multiple identical organisms rather than a single organism, so the life span of a coral is more of a team effort. Deep-water black corals are among the corals that live the longest. According to Live Science, black coral specimens discovered off the coast of Hawaii have been radiocarbon dated to be 4,265 years old.