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Cetaceans
Whales, dolphins, and porpoises all belong to the same taxonomic order called cetaceans. Cetaceans are comprised of about 80 kinds of whales, dolphins, and porpoises. The word cetacean is derived from the Latin "cetus" (a large sea animal) and the Greek "ketos" (sea monster).
WhalesWhales are the largest mammals on Earth, Larger than the largest of ancient dinosaurs, one species of whale, the great Blue whale, is the largest creature that has ever lived on Earth. and can grow up to 30m or 88 ½ foot long and weigh over 200 tonnes. Being a mammal implies that they are warm-blooded, give birth like humans and feed their young with their milk. It takes about 5 to 8 years for a female to reach sexual maturity and their 16-19 ft. calves are usually born only every three years. They have existed for 18 million years and thus are also the most ancient. They are considered one of the most intelligent mammals on Earth. They developed the largest brain of any creature alive, which is the size of a car. They are the oldest mammals on Earth and can live up to 200 years. Whales have used echolocation to locate food and scan their environment for millions of years, whereas we have only been using echolocation since it was discovered in 1917 by Paul Langevin. They are the most peaceful creatures and don’t kill larger or other intelligent life forms. The world’s largest mammals roam in the world’s largest space. Over 70% of the Earth is covered in ocean and the nice thing about living in the ocean is the weightlessness effect of water. Whales dominate peacefully whilst maintaining their environment in a sustainable way. The oceans largest inhabitants feed on almost the smallest – krill, which are only 1.5 – 3 cm long. The Blue whale’s heart is the size of a car, their tongue the size of an elephant, some of its blood vessels are wide enough to swim through. Its tail is the width of a small aircraft's wingspan. It’s streamlining is close to perfection and enables it to cruise at 20 knots which makes them one of the fastest animals in the sea. Each year Gray whales migrate between their summer feeding grounds in the Bering, Chukchi, and Beaufort Seas to their winter breeding grounds off Baja California, Mexico. This is one of the longest migrations by a mammal species. The Sperm whale is the most famous of the Physeteridae family. It is also the largest of the toothed whales and may dive deeper than any other cetacean. Whales do not have any natural predators, apart from humans. Long live the Great Whales! Blue Whale Video, Planet Earth The Future narrated by David Attenborough Nearly 90% of cetacean species are toothed whales. Most toothed whales are small dolphins and porpoise. Toothed whales have 1 to 65 teeth depending on the species and tend to be smaller than baleen whales. Toothed whales have a single blowhole and do not have baleen plates. There are several families of Odontoceti, or toothed whales, including Sperm whales, Pygmy Sperm whales, over 20 different species of Beaked whales, River dolphins (3 families) Belugas and Narwhales, dolphins and porpoises. Baleen whales are very large, have paired blow holes, and characteristic baleen plates used for filtering food from the ocean. Baleen whales are the largest animals on earth, yet they feed on some of the smallest animals in the ocean.
There are 12 baleen whale species divided into 4 families: Northern Right whale and the Southern Right, Pygmy Right, Gray and Bowhead whale. There are the species of Rorqual whales including the Humpback whale, Fin whale, Bryde's whale, Northern and Southern Blue whale, Northern Hemisphere Minke and the Antarctic Minke.
DolphinsDolphins are Cetaceans and belong to the family Delphinidae. The largest dolphin is the Killer whale, Orcinus Orca being 23 feet (7 meters) long; the smallest is the Heaviside’s dolphin, Cephalorhynchus heavisidii being 3.5 feet (1.2 meters) long. The Killer whale weighs up to 4.48 tons (4.55 tonnes); and the Heaviside’s dolphin up to 88 pounds (40 kilograms). Their life span can reach up to 100 years, depending on species. Gestation is usually 10 to 12 months for most species and they usually have one calf which weighs between 10 to 400 pounds (4.5 to 180 kilograms), depending on species and they reach their age of maturity at 6 to 15 years, depending on species. Dolphins have an eye on each side of their head. Each eye moves independently of the other, so dolphins can see ahead, to the side, and behind them. They can also see very well both underwater and in the air. Members of the dolphin, or Delphinidae family, usually have teeth in both jaws. We can find four different species of river-dolphins: Indian river-dolphin (Indus and Ganges river-dolphins), Amazon river-dolphin (Boto), Yangtse river-dolphin (Baiji), and the La Plata dolphin. The Baiji Yangtze Dolphin is with all probability gone extinct in December 2006. There are only two species in the Monodontidae family, the Narwhale and the Beluga (white whales).
Long live the Dolphins!
PorpoisePorpoise species include the Harbour porpoise, Gulf of California porpoise. The dorsal fin on a porpoises is triangular in shape unlike the hooked dorsal fin of dolphins. Porpoises grow up to 7 feet (2.1 meters)
Long live the Porpoises!
Whale Communication System
Listen to the highly developed communication of whales and dolphins. We may not be able to translate the language but it certainly shows how sophisticated and creative these beings are. Videos:
Japan, Norway, Canada, Greenland, Russia, Denmark, Iceland and South Korea have been whaling to various degrees.
Please take a second and save a whale's life. The key governments in the debate need to hear from you that you demand that the International Whaling Commission works to protect whales. Sign the letter here
Noise PollutionWhales depend on sound for navigation and communication for finding food. Both traffic and industrial activity can increase underwater noise which can reduce the whales' ability to communicate.
Protect Whales from Sonar! Send a Citizen Comment urging the National Marine Fisheries Service to reject the Navy's plan for worldwide deployment of dangerous LFA sonar.
Whale Migration
Dotted lines show migration routes of three species of whales through BioGem
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