Ever since a sperm whale (Physeter macrocephalus) head-butted and sunk a whaler’s ship in 1821, whalers and scientists have theorized that the mammals’ uniquely boxy foreheads might be adapted for use as battering rams—possibly for male-on-male battles over access to females. But not everyone agrees, especially because the structures that would be front and center in an impact are important for producing the whale’s clicking communication. In a new study, researchers tested the idea by running virtual crash tests: Using a model of a sperm whale skull constructed using already published data, they simulated ramming impacts, and recorded where in the skull these impacts produce the most mechanical stress. To examine the role of internal structures, the researchers also removed the vertical tissues that divide up the large, oil-filled organ called the “junk” in some models. The simulations showed that these junk compartments help spread the force of impact over the skull, and removing the compartments increased overall stress on the skull by 45%. Plus, the compartment tissues are thickest near the front of the skull—the same area where impact forces are the most intense, the authors report today in the journal PeerJ. Male ramming behavior has only been observed once in sperm whales. But based on their ram-ready skulls, the authors say, these contests may be occurring below the surface.
Based on the 2000 book by Nathaniel Philbrick, it’s a loose retelling of the 1821 sinking of the whaleship Essex, after an enormous sperm whale bashed in its hull with its head. The story eventually helped inspire Herman Melville’s 1851 novel, Moby-Dick, which describes a whaleship captain’s self-destructive obsession with hunting down the white sperm whale that sank a previous ship and severed his leg.
What is threatening the grey Whales?
This is another type of Whales
The grey whale lived around 300years ago in the Atlantic and pacific oceans. The giant animals were hunted extensively for their meat and oil. They became extinct in the Atlantic by the end of the 17th century, but can still be found in the pacific ocean. Around 20,000 animals migrate every year in October from Alaska in the north to the coast of Mexico, where they give birth to their young ones in winter. In west pacific, there are at most 200 grey whales at present and they are listed as critically endangered. These animals are sensitive to noise and are being displaced from their habitat because of the construction of drilling rigs for the crude oil industry.
The gray whale is distributed in an eastern North Pacific (North American), and an endangered western North Pacific (Asian), population. North Atlantic populations were extirpated (perhaps by whaling) on the European coast before AD 500, and on the American coast around the late 17th to oearly 18th centuries.The gray whale is one of the animal kingdom's great
migrators.
Traveling in groups called pods, some of these giants swim 12,430 miles round-trip from their summer home in Alaskan waters to the warmer waters off the Mexican coast. The whales winter and breed in the shallow southern waters and balmier climate. Other gray whales live in the seas near Korea.
Like all whales, gray whales surface to breathe, so migrating groups are often spotted from North America's west coast. These whales were once the target of extensive hunting, and by early in the 20th
century they were in serious danger of
extinction.
Let's come to the point
Today gray whales are protected by international law, and their numbers have grown. In 1994, the gray whale was removed from the United States endangered species list.
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