Title: Largest organisms
Content: namadicus" may have been the largest land mammal ever, based on extensive research of fragmentary leg bone fossils from one individual, with a maximum estimated size of 22 tonnes. The Permian era "Cotylorhynchus", from what is now the southern United States, probably was the largest of all synapsids (most of which became extinct 250 million years ago), at and 2 tonnes. The largest carnivorous synapsid was "Anteosaurus" from what is now South Africa during Middle Permian era. "Anteosaurus" was long, and weighed about . The largest living reptile, a representative of the order Crocodilia, is the saltwater crocodile ("Crocodylus porosus")

Title: Animal
Content: measuring up to long. The largest terrestrial animals that ever lived were titanosaur sauropod dinosaurs such as "Argentinosaurus", which may have weighed as much as 73 tonnes. Several animals are microscopic; some Myxozoa (obligate parasites within the Cnidaria) never grow larger than 20 µm, and one of the smallest species ("Myxobolus shekel") is no more than 8.5 µm when fully grown. The following table lists estimated numbers of described extant species for the animal groups with the largest numbers of species, along with their principal habitats (terrestrial, fresh water, and marine), and free-living or parasitic ways of life. Species estimates

Title: Sauropoda
Content: comparison, the giraffe, the tallest of all living land animals, is only 4.8 to 5.5 metres (16 to 18 ft) tall. The best evidence indicates that the most massive were "Argentinosaurus" (120 metric tons), "Puertasaurus" (80 to 100 metric tons ), "Alamosaurus", "Paralititan", "Antarctosaurus" (69 metric tons). There was poor (and now missing) evidence that so-called "Bruhathkayosaurus", might have weighed over 175 metric tons but this has been questioned. The weight of "Amphicoelias fragillimus" was estimated at 122.4 metric tons but 2015 research argued that these estimates may have been highly exaggerated. The largest land animal alive today, the Savannah

Title: Largest prehistoric animals
Content: size. Total length was probably up to in female and they weighed about . The largest extinct "Titanohierax" was a giant hawk about 8 kilograms that lived in the Antilles, where it was among the top predators. The largest-known in this group was a giant flightless "Sylviornis", a bird long and weighing up to about . The largest-known songbird is the extinct giant grosbeak ("Chloridops regiskongi") at long. The largest-known cormorant was the spectacled cormorant of the North Pacific ("Phalacrocorax perspicillatus"), which became extinct around 1850, was larger still, averaging around and . The largest-known in this group—which has been

Title: Largest organisms
Content: and Newfoundland, but is less common here than in the east, and occurs only at depths between . The largest lancelets: European lancelet ("Branchiostoma lanceolatum") "primitive fish". It can grow up to 6 cm (2.5 in) long. The blue whale is the largest mammal. The largest land mammal extant today is the African bush elephant. The largest extinct land mammal known was long considered to be "Paraceratherium orgosensis", a rhinoceros relative thought to have stood up to tall, measured over long and may have weighed about 17 tonnes. In 2015, a study suggested that one example of the proboscidean "Palaeoloxodon

Question: Which is the largest animal ever to have inhabited the Earth?
Answer: Blue Whale