Jamaica Produced The Most Primitive Manatee Fossil
It's of something that looks nothing like today's manatee.
A fossil of the world's most primitive sirenian (Prorastomus sirenoides) was discovered in Jamaica. It is a 50-million-year-old, 4-legged, pig-sized mammal which is one of the best examples uncovered so far showing the intermediate stage of the transition from a land to an aquatic animal.
Paleontologist Daryl Domning of Howard University reported this is the first whole skeleton found where the legs could support the animal out of water. The fossil is of an animal almost 7 feet long that may have weighed several hundred pounds.
Largest in size of all surviving manatee species is the West Indian manatee. It is divided into two subspecies, the Florida manatee ( Trichechus manatus latirostris ) and the Antillean manatee (Trichechus manatus manatus).
The distinction is based on the differences in internal skull characteristics, not something that can be detected visually.
The Antillean manatee is found in 19 different countries, including Puerto Rico, Jamaica , the Dominican Republic, Trinidad, Guyana , Belize , Surinam, French Guyana, certain parts of South America, and Mexico.
The largest group, over 300, is believed to live in the waters of Belize where they have become a major tourist attraction. In most other countries the population is thought to be fewer than a hundred animals.
The West Indian manatee has 3 surviving relatives around the world. They are the Amazonian manatee (Trichechus inunguis), which lives only in the fresh water upper regions of the Amazon River; the West African manatee (Trichechus senegalensis), found in western Africa; and the dugong ( Dugong dugon), scattered throughout the Indo-Pacific, primarily in Australian waters. At one time the dugong also lived in Florida and the Caribbean .
How the manatee got its common name is uncertain. The term evidently has its roots in the Carib Indian word "manati," meaning "woman's breast."
Perhaps an unlikely term to apply to a marine animal, but the manatee is a mammal and its mammae do resemble those of a human.