What is the Difference Between Cetacea and Sirenia?

Cetacea and Sirenia are two taxonomic orders of aquatic mammals. The main differences between them are:

1. Size: Cetaceans are large carnivorous aquatic mammals, while Sirenians are small herbivorous aquatic mammals.
2. Habit: Cetaceans are carnivorous and predatory, whereas Sirenians are herbivorous and feed on aquatic plants.
3. Hairs: Cetaceans have no hair, except for a few bristles around the muzzle, while Sirenians have sparse hairs.
4. Caudal fin: Cetaceans have horizontally expanded caudal fins, usually divided into 'flukes', while Sirenians have horizontally flattened caudal fins.
5. Dorsal fin: Cetaceans have a dorsal fin, while Sirenians do not.
6. Eyes: Cetaceans have small eyes without a third eyelid, while Sirenians have small eyes with a third eyelid.

Examples of Cetaceans include the Ganges dolphin, sperm whale, porpoise, and blue whale. Sirenian examples include manatees and the dugong. Both orders of mammals are warm-blooded, have lungs, and possess a more complex brain.

Comparative Table: Cetacea vs Sirenia

Here is a table summarizing the differences between Cetacea and Sirenia:

Cetacea and Sirenia are two taxonomic orders of aquatic mammals. Cetaceans are large carnivorous aquatic mammals, while sirenians are small herbivorous aquatic mammals.