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More About Whales ...
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Whales are the largest species of exclusively aquatic placental mammals, members of the order Cetacea, which also includes dolphins and porpoises. The term whale is ambiguous: it can refer to all cetaceans, just the largest ones, or only to members of particular families within the order Cetacea. This latter definition is the one followed within Wikipedia. Whales are those cetaceans which are neither dolphins (i.e. members of the families Delphinidae or Platanistoidae) or porpoises. This can lead to some confusion as Orca (Killer Whales) and Pilot Whales have "whale" in their name, but are dolphins from the perspective of classification. Cetologists tend not to worry too much about making a distinction.
Like all members of the order, whales evolved from land mammals which returned to the sea undergoing aquatic adaptation, probably in the Eocene, between 55 and 34 million years ago. The precise ancestry of whales is still obscure, as there is no commonly agreed succession, but they are thought to have evolved from a group of carnivorous artiodactyla (even-toed hoofed animals). In 2001, two important 47-million-year-old partial fossils, named Rodhocetus balochistanensis and Artiocetus clavis, were discovered in Balochistan, Pakistan. These fossils represent intermediate forms between land-living ungulates and whales and are evidence that the whales' closest relatives on land might be hippos, which had been previously suggested by DNA studies. The first fully marine cetaceans, like Basilosaurus, appeared 40 million years ago.
Like all mammals, whales breathe air into lungs, are warm-blooded (i.e., endothermic), breast-feed their young, and have some (very little) hair. The whales' adaptions to a fully aquatic life are quite conspiciuous: The body is fusiform, resembling that of a fish. The forelimbs, also called flippers, are paddle-shaped. The end of the tail holds the fluke, which provides propulsion by vertical movements. Whales do not possess hind limbs, small bones inside the body are the only remains of the pelvis. Most species of whales bear a fin on their backs. Beneath the skin lies a layer of fat, the blubber. It serves as an energy reservoir and also as insulation. Whales have a four-chambered heart. The neck vertebrae are fused in most whales, whhich provides stability during swimming at the expense of flexibility. Whales breathe through blowholes, located on the top of the head so the animal can remain submerged. Baleen whales have two, toothed whales one blowhole. When breathing out after a dive, a spout can be seen from the right perspective, the shape of which differs among the species. Whales have a unique respiratory system that lets them stay underwater for long periods of time without taking any oxygen. Some whales, such as the Sperm Whale, can stay underwater for up to two hours in a single breath.
Whale females give birth to a single calf. Nursing time is long (more than one year in many species), which is associated with a strong bond between mother and young. In most whales reproductive maturity occurs late, typically at seven to ten years. This strategy of reproduction spawns few offspring, provided with a high rate of survival
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Source: Wikipedia Read more about Whales
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VIDEO CLIPS
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Humpback Whale
5.460MB MOV View Movie
Banderas Bay Humpback Whales
humpback slapping tail to surface
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Humpback Whale
4.020MB MOV View Movie
Banderas Bay Humpback Whales
Three humpbacks, a single adult female, a calf, and an escort male
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Humpback Whale
6.880MB MOV View Movie
Banderas Bay Humpback Whales
Two whales having fun
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Humpback Whale
0.860MB MOV View Movie
Banderas Bay Humpback Whales
Humpbacks showing acrobatics (breaching)
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Blue Whale
1.030MB TML View Movie
Mike Johnson Marine Natural History Photography
Blue Whale
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Blue Whale
0.180MB TML View Movie
Mike Johnson Marine Natural History Photography
Blue Whale
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Blue Whale
0.040MB TML View Movie
Mike Johnson Marine Natural History Photography
Blue Whale diving
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Blue Whale
0.030MB GIF View Movie
Mike Johnson Marine Natural History Photography
Blue Whale
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Great White Shark
2.140MB MOV View Movie
Extreme Science
Great White Shark attacks Killer Whale
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Fin whale
1.040MB AVI View Movie
University of Aberdeen Zoology Museum
Fin whale
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Humpback whale
1.170MB MOV View Movie
Ocean stock footage
Mating humpback whales, French Polynesia
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Humpback whale
0.640MB MOV View Movie
Ocean stock footage
Humpback whale, Moorea, French Polynesia
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Humpback whale
0.930MB MOV View Movie
Ocean stock footage
Humpback whales and dolphins
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Humpback whale
0.300MB MOV View Movie
Ocean stock footage
Humpback whale breaching
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Blue Whale
1.240MB MOV View Movie
Ocean stock footage
Aerial shot of whales
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Gray Whale
0.920MB MOV View Movie
Ocean stock footage
Gray mother whale and calf
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Sperm Whale
12.890MB MOV View Movie
Whalenet
Sperm Whale Satellite Tagging in the Azores
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Blue Whale
3.650MB MOV View Movie
Whalenet
Closeup of Blue whales, one with a satellite tag
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Blue Whale
4.150MB MOV View Movie
Whalenet
Blue Flukes & Biopsy Sample
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Blue Whale
0.840MB MOV View Movie
Whalenet
Blue Whale Satellite Tag
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Fin Whale
3.250MB MOV View Movie
Whalenet
Excellent footage of fin whales & dolphins together; annotated example of identifying field marks
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Whale
0.960MB MOV View Movie
Whalenet
Demonstration of whale flipper slapping
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Whale
1.960MB MOV View Movie
Whalenet
Watch a whale feed! View ventral pleats.
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Minke Whale
3.290MB MOV View Movie
Whalenet
Narrated rare minke sighting
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Humpback Whale
1.670MB MOV View Movie
Whalenet
Spy Hop by Humpback Whale
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Fin whale
3.760MB MPG View Movie
Newfoundland and Labrador, Canada
Fin whale spraying out from the sea surface.
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Fin whale
0.990MB MPG View Movie
Newfoundland and Labrador, Canada
Underwater view of fin whale
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Fin whale
0.350MB MPG View Movie
Newfoundland and Labrador, Canada
Fin whale with Newfoundland's sea shore in the background
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Whale
0.620MB MPG View Movie
Newfoundland and Labrador, Canada
Whale release movie
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Whale
2.020MB MPG View Movie
Newfoundland and Labrador, Canada
Whale release movie
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Whale
1.120MB MPG View Movie
Newfoundland and Labrador, Canada
Whale release movie
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Killer Whale
Streaming RAM View Movie
National Geographic - Creature Feature Archive
Video of Killer Whales
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North Atlantic Right Whale
0.530MB MOV View Movie
CNN
Right whale takes a breath
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Gray Whale
1.280MB MOV View Movie
CNN
Gray whales off the coast of Washington
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Humpback Whale
Streaming RAM View Movie
National Geographic
Humpback whales logging
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Sperm Whale
Streaming RM View Movie
PBS
Demon of the Sea?
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