Search results
The two extant families of sirenians are thought to have diverged in the mid-Eocene, after which the dugongs and their closest relative, the Steller's sea cow, split off from a common ancestor in the Miocene. The Steller's sea cow became extinct in the 18th century. No fossils exist of other members of the Dugongidae. [19]
The singing of the monstrous sea-nymphs bewitched approaching sailors and lured them to crash their ships on the rocks. With a nod to Colombus and Greek mythology, seacows are technically known as sirenians, an order comprising, today, just three manatee species and one dugong species. In the past they were more diverse and more widespread.
Sirenians, or seacows, are a group of marine mammals that include manatees and dugongs. In the modern ocean, only one species of seacow is found in each world region, however, the fossil record tells a different story.
Sirenians typically make two- to three-minute dives, [36] but manatees can hold their breath for up to 15 minutes while resting [34] and dugongs up to six minutes. They may stand on their tails to hold their heads above water.
Sirenia is the order of placental mammals which comprises modern "sea cows" (manatees and the Dugong) and their extinct relatives. They are the only extant herbivorous marine mammals and the only group of herbivorous mammals to have become completely aquatic. Sirenians are thought to have a 50-million-year-old fossil record (early Eocene-recent).
Dugong calves are about 3.3 to 3.9 feet (1 to 1.2 meters) and weigh 44.1 to 66.2 pounds (20 to 30 kilograms). Dugongs can live for seventy years. Because Steller's sea cow died out so quickly, most of what we know is speculation, an educated guess based on facts.
The extinct Steller’s sea cow (Hydrodamalis gigas), formerly of the Bering Sea, also belonged to the dugong family, but all were killed off by humans less than 30 years after they were first scientifically described in 1741. Steller’s sea cow was the largest sirenian and one of the few sirenians to occupy cold water.
People also ask
When did the dugongs split off from the sirenians?
Is a dugong a sirenian?
How do sirenians differ from dugongs & manatees?
Are dugongs extinct?
How many species of Sirenia are there?
Why are seacows called sirenians?
