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Indus river dolphin AI simulator
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Hub AI
Indus river dolphin AI simulator
(@Indus river dolphin_simulator)
Indus river dolphin
The Indus river dolphin (Platanista minor) is a species of freshwater dolphin in the family Platanistidae. It is endemic to the rivers of the Indus basin in Pakistan and northwestern India. This dolphin was the first discovered side-swimming cetacean. In Pakistan, it occurs in the Indus river, patchily distributed in five small sub-populations that are separated by irrigation barrages. In India, a very small isolated population at a very high risk of extinction lives in the Beas river.
From the 1970s until 1998, the Ganges River dolphin (Platanista gangetica) and the Indus dolphin were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of the South Asian river dolphin. However, more recent studies support them being distinct species. It is listed as the national mammal of Pakistan and the state aquatic animal of Punjab, India.
The Indus river dolphin was described in 1853 by Richard Owen under the name Platanista gangetica, var. minor, based on a dolphin skull, which was smaller than skulls of the Ganges river dolphin.
The Indus and Ganges river dolphins were initially classified as a single species, Platanista gangetica. In the 1970s, they were considered to be distinct species, but again grouped as a single species in the 1990s. However, more recent studies of genes, divergence time, and skull structure support both being distinct species.
The Ganges river dolphin split from the Indus river dolphin during the Pleistocene, around 550,000 years ago.
The Indus dolphin has the long, pointed nose characteristic of all river dolphins. The teeth are visible in both the upper and lower jaws even when the mouth is closed. The teeth of young animals are almost an inch long, thin and curved; however, as animals age the teeth undergo considerable changes and in mature adults become square, bony, flat disks. The snout thickens towards its end. The species does not have a crystalline eye lens, rendering it effectively blind, although it may still be able to detect the intensity and direction of light. Navigation and hunting are carried out using echolocation. The body is a brownish color and stocky at the middle. The species has a small triangular lump in place of a dorsal fin. The flippers and tail are thin and large in relation to the body size, which is about 2–2.2 m (6 ft 7 in – 7 ft 3 in) in males and 2.4–2.6 m (7 ft 10 in – 8 ft 6 in) in females. The oldest recorded animal was a 28-year-old male 199 cm (78 in) in length. Mature adult females are larger than males. Sexual dimorphism is expressed after females reach about 150 cm (59 in); the female rostrum continues to grow after the male rostrum stops growing, eventually reaching approximately 20 cm (7.9 in) longer.[citation needed]
The Indus river dolphin presently only occurs in the Indus River system. Its range once stretched over about 3,400 km (2,100 mi) of the Indus River and its tributaries, but today, it only occurs in about 690 km (430 mi) of the river, and its range has declined by 80% since 1870; it is not present anymore in the tributaries. A remnant population is present in the Beas River and Harike Wetland located in Punjab, India.
Since the two originally inhabited river systems – between the Sukkur and Guddu barrage in Pakistan's Sindh Province, and in the Punjab and Khyber Pakhtunkhwa Provinces – are not connected in any way, how they were colonized remains unknown. The river dolphins are unlikely to have travelled from one river to another through the sea route, since the two estuaries are very far apart. A possible explanation is that several north Indian rivers such as the Sutlej and Yamuna changed their channels in ancient times while retaining their dolphin populations.
Indus river dolphin
The Indus river dolphin (Platanista minor) is a species of freshwater dolphin in the family Platanistidae. It is endemic to the rivers of the Indus basin in Pakistan and northwestern India. This dolphin was the first discovered side-swimming cetacean. In Pakistan, it occurs in the Indus river, patchily distributed in five small sub-populations that are separated by irrigation barrages. In India, a very small isolated population at a very high risk of extinction lives in the Beas river.
From the 1970s until 1998, the Ganges River dolphin (Platanista gangetica) and the Indus dolphin were regarded as separate species; however, in 1998, their classification was changed from two separate species to subspecies of the South Asian river dolphin. However, more recent studies support them being distinct species. It is listed as the national mammal of Pakistan and the state aquatic animal of Punjab, India.
The Indus river dolphin was described in 1853 by Richard Owen under the name Platanista gangetica, var. minor, based on a dolphin skull, which was smaller than skulls of the Ganges river dolphin.
The Indus and Ganges river dolphins were initially classified as a single species, Platanista gangetica. In the 1970s, they were considered to be distinct species, but again grouped as a single species in the 1990s. However, more recent studies of genes, divergence time, and skull structure support both being distinct species.
The Ganges river dolphin split from the Indus river dolphin during the Pleistocene, around 550,000 years ago.
The Indus dolphin has the long, pointed nose characteristic of all river dolphins. The teeth are visible in both the upper and lower jaws even when the mouth is closed. The teeth of young animals are almost an inch long, thin and curved; however, as animals age the teeth undergo considerable changes and in mature adults become square, bony, flat disks. The snout thickens towards its end. The species does not have a crystalline eye lens, rendering it effectively blind, although it may still be able to detect the intensity and direction of light. Navigation and hunting are carried out using echolocation. The body is a brownish color and stocky at the middle. The species has a small triangular lump in place of a dorsal fin. The flippers and tail are thin and large in relation to the body size, which is about 2–2.2 m (6 ft 7 in – 7 ft 3 in) in males and 2.4–2.6 m (7 ft 10 in – 8 ft 6 in) in females. The oldest recorded animal was a 28-year-old male 199 cm (78 in) in length. Mature adult females are larger than males. Sexual dimorphism is expressed after females reach about 150 cm (59 in); the female rostrum continues to grow after the male rostrum stops growing, eventually reaching approximately 20 cm (7.9 in) longer.[citation needed]
The Indus river dolphin presently only occurs in the Indus River system. Its range once stretched over about 3,400 km (2,100 mi) of the Indus River and its tributaries, but today, it only occurs in about 690 km (430 mi) of the river, and its range has declined by 80% since 1870; it is not present anymore in the tributaries. A remnant population is present in the Beas River and Harike Wetland located in Punjab, India.
Since the two originally inhabited river systems – between the Sukkur and Guddu barrage in Pakistan's Sindh Province, and in the Punjab and Khyber Pakhtunkhwa Provinces – are not connected in any way, how they were colonized remains unknown. The river dolphins are unlikely to have travelled from one river to another through the sea route, since the two estuaries are very far apart. A possible explanation is that several north Indian rivers such as the Sutlej and Yamuna changed their channels in ancient times while retaining their dolphin populations.
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