The largest animal currently alive is the blue whale. The maximum recorded weight was 190 tonnes (209 US tons) for a specimen measuring 27.6 metres (91 ft), whereas longer ones, up to 33 metres (108 ft), have been recorded but not weighed.[1][2][3] It is estimated that this individual could have a mass of 250 tonnes or more.[4][5][6] The longest non-colonial animal is the lion's mane jellyfish (37 m, 120 ft).[7]
In 2023, paleontologists estimated that the extinct whale Perucetus, discovered in Peru, may have outweighed the blue whale, with a mass of 85 to 340 t (94–375 short tons; 84–335 long tons).[8] However, more recent studies suggest this whale was much smaller than previous estimates putting its weight at 60 to 113 tonnes.[9] While controversial, estimates for the weight of the sauropodBruhathkayosaurus suggest it was around 110–170 tons, with the highest estimate being 240 tons, if scaled with Patagotitan, although actual fossil remains no longer exist, and that estimation is based on described dimensions in 1987.[10] In April 2024, Ichthyotitan severnensis was established as a valid shastasaurid taxon and is considered both the largest marine reptile ever discovered and the largest macropredator ever discovered. The Lilstock specimen was estimated to be around 26 metres (85 ft) whilst the Aust specimen was an even more impressive 30 to 35 metres (98 to 115 ft) in length. Whilst no weight estimates was made as of yet, Ichthyotitan would have easily rivalled or surpassed the blue whale.[11][12] The upper estimates of weight for these prehistoric animals would have easily rivaled or exceeded the largest rorquals and sauropods.[13]
The African bush elephant (Loxodonta africana) is the largest living land animal. A native of various open habitats in sub-Saharan Africa, males weigh about 6.0 tonnes (13,200 lb) on average.[14] The largest elephant ever recorded was shot in Angola in 1974. It was a male measuring 10.67 metres (35.0 ft) from trunk to tail and 4.17 metres (13.7 ft) lying on its side in a projected line from the highest point of the shoulder, to the base of the forefoot, indicating a standing shoulder height of 3.96 metres (13.0 ft). This male had a computed weight of 10.4 to 12.25 tonnes.[1]