Whales dont spray water from their blowholes and other myths, debunked
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On land where light is abundant, humans see the world using three specific color receptors. But underwater light is filtered, and in deeper water, many wavelengths are lost so that colors lose their vibrancy, fading altogether at deeper depths. Whales, adapting to this environment, only have one color receptor—they see in greyscale, which allows them to see better in the low light and they have large pupils to allow as much light in as possible. However, the murky waters of the Ganges have proven too dark for the river dolphins that live there.
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Sensory Organs
With fewer than 450 individuals left, North Atlantic right whales are considered endangered and until 2013, researchers were unsure where they mated. In 2014, researchers determined that this species gathered to reproduce in waters off the Gulf of Maine during the Northern Hemisphere winter. The species can be seen in groups at the surface of the water nuzzling, rubbing, and generally jostling for a mate, in what researchers think is courtship behavior. Dolphins also show signs of courtship behavior, sometimes crossing over to aggressive mating behavior, and sexual behavior unrelated to reproduction. Some species with more narrow face shapes, such as dolphins and beluga whales, can see with binocular vision—where they stitch together a single image, the way humans see. Despite losing their visible hair, whales continue to depend on their sensory hair to navigate underwater.
Most diverse songs
The bubbles will merge together and rise to the surface, causing confusion and producing a de facto net that surrounds schooling fish they have encountered. Then, other whales will rise up through the center forcing the fish towards the surface where they are gulped like fish in a barrel. Bubble net feeding, as it’s called, is only seen in humpback whales during the feeding season. Gray whales, in contrast, feed close to the seafloor where they suck up prey in the muddy sediment that they filter through their baleen.
Rogue orcas are thriving on the high seas—and they’re eating big whales
Today, most nations observe the whaling ban put in place by the International Whaling Commission (see Conservation section). Only a few nations, including Iceland, Japan, and Norway, object to the ban and continue to whale. The IWC also allows certain aboriginal groups from Canada, the U.S., Greenland, Russia, South-Eastern Asia, and the Caribbean to whale since it has been deemed an integral part of their nutritional and cultural life. The Hr gene is responsible for encoding a protein that regulates hair follicle cycling, and changes in this gene may have affected hair loss in cetaceans. In contrast, the FGF5 gene plays a role in hair follicle development and morphology, and changes in this gene may have influenced the hair loss process. Positive selection for the FGF5 gene in cetaceans may have promoted hair growth termination and early entry into the catagen stage of hair follicle cycling.
Not all whales sing
In summary, hair on whales and dolphins might serve multiple functions, from helping them locate prey to facilitating communication and navigation. Hippos are the closest living relatives of whales, but they are not the ancestors of whales. Both hippos and whales evolved from four-legged, even-toed, hoofed (ungulate) ancestors that lived on land about 50 million years ago. Modern-day ungulates include hippopotamuses, giraffes, deer, pigs, and cows. Unlike the hippo’s ancestor, whale ancestors moved to the sea and evolved into swimming creatures over a period of about 8 million years.
Do baleen whales have hair?
Cetaceans are broadly divided into two groups, depending on whether they have teeth (odontocetes) or baleen (mysticetes). Eleanor is a content creator and social media assistant with an undergraduate degree in zoology and a master’s degree in wildlife documentary production.
Animals
Toothed whales, unlike baleen whales, hunt prey directly and do not require the elaborate filtering mechanism provided by baleen. Cetaceans include the largest living animals on the planet, but some of the smallest can be found living on and in whales, dolphins, and porpoises. Small crustaceans called whale lice live in folds and rough patches of their skin, as well as in their lesions and nostrils. Most whale louse species have an exclusive corresponding cetacean species that acts as the host for their entire life cycle. Male and female sperm whales even have different unique lice species that they host. Whales are extraordinary marine mammals with several unique adaptations to their aquatic environment.
Equally, the earliest whales may have experienced pressures from other predators on land, or they returned to the ocean for reasons that we cannot fully test. Whales have also adapted the shape of their eye to better see underwater. Terrestrial animals, including humans, rely on the cornea—the clear outer layer of the eye—to focus images using a property called refraction, a bending of light as it crosses through different materials. As light travels through the air and enters the eye, it bends and creates a focused image on the retina with a bit of help from the lens. Underwater, terrestrial animals become far-sighted because the fluid of the eye and the water are so similar; light doesn’t bend enough and the image doesn’t focus effectively.
The Norwegian whalers initially hunted close to home, but by 1904 they began to expand throughout the world, establishing whaling stations as they went. In the 1920s, they also introduced pelagic-factory ship whaling where the entire whale was hauled on deck to be processed at sea. Other advances included processing machinery, radio, the use of fleets with many specialized vessels, and aircraft spotting. Whaling became so efficient that by World War II many species were on the brink of extinction.
Historians think the first description of a horned horse comes from Greek physician Ctensias of Cnidus in 398 B.C., though it also finds its way into the Bible through a series of mistranslations. Then during the Middle Ages, Viking traders likely introduced narwhal tusks to European markets. Unfamiliar with this Arctic whale species, the existence of the narwhal tusk became proof of the unicorn. Evidence for this theory includes depictions of unicorns in artwork with a spiraled horn.
There are over 80 species of whales, and hair is only visible in some of these species. In some adult whales, you can't see hair at all, as some species only have hair when they are fetuses in the womb. It is likely that these accounts influenced the stories we are familiar with today. In the Bible, Jonah becomes imprisoned in a whale’s stomach for three days, a theme that is mirrored in Disney’s Pinocchio from 1940. Herman Melville’s famous story of Moby Dick, published in 1851, also features a villainous sperm whale that Captain Ahab chases to enact revenge.
By the 1970s, public awareness halted the capture of orcas off the coast of British Columbia and Washington, and in 1976 the last orca was taken from the region. Iceland then became the main source of whales for marine parks—between 1955 and 1972, 300 orcas were captured from Icelandic waters for the marine park industry. In later years marine parks resorted to breeding their captive whales, and in 2004 the first live births from artificial insemination occurred. In the 1860s a Norwegian entrepreneur revolutionized the whaling process and ushered in a new, modern era of whaling. Sven Foyn’s boats were steam-powered and equipped with deck cannons that shot harpoons that exploded on impact.
These whales have a characteristic hump on their back, right before their dorsal fin. Another striking feature is their long side fins and the grooves on their underside. Scientists have discovered that blues can sing for days and have found 11 different song types around the world that may correspond to distinct populations of blue whales. They have also found that blue whales migrate over large distances and produce songs throughout the year - at their tropical breeding grounds, during migration, and on their feeding grounds.
In baleen whales, between the blowhole and the lungs there is a special larynx called the U-fold that directly connects to a unique, expandable sac within the whale’s chest. When the whale “talks,” air flows from the lungs, through the U-fold, and then fills the sac. The vibrations made by the U-fold reverberate within the air-filled sac, a system that allows these whales to create a sound loud enough to travel thousands of kilometers.
Most baleen whales take their large gulps of seawater close to the surface—species such as rorquals lunge-feed in a single gulp, while right whales skim continuously with their mouths agape. Researchers have found that blue whales complete 360 degree turns while lunging with wide open mouths to align their mouths with the swarm of prey and get the most possible krill. A blue whale can eat as much as one ton of krill per day at the peak of feeding time in Antarctica and fit as much as 150 percent of its body weight worth of water in one gulp. One whale will dive down and begin to produce bubbles in a circle below the surface of the water.
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