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These spouts vary in size and shape based on the species and can be used to identify a species from afar. Whales are known for their surface antics—searching for a view of them at the surface is the basis for a booming tourism industry. Cetaceans need to spend a certain amount of time at the surface of the water to breathe air but, as those on whale watching tours know, they do more than just breathe there. While these marine mammals are at the surface catching a breath, they engage in many other behaviors for feeding and communication. Sperm whales, pygmy sperm whales (Kogia breviceps) and dwarf sperm whales (Kogia sima) make up the Physeteroidea group.
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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.
Brain power
Studying the molecular composition of the baleen will enable scientists to determine what kinds of food the whales ate and which oceans they swam in. Taken together, this information can paint an accurate picture of what life in the ocean was like for these whales some 75 years ago and enables us to understand how the ocean and its whales have changed over time. Because of these efforts, in 2016 most humpback whale populations were removed from the endangered species list.
Animals
Unsolved mystery: What are those weird bumps on the heads of humpback whales? - Earth Touch News
Unsolved mystery: What are those weird bumps on the heads of humpback whales?.
Posted: Fri, 28 Feb 2014 08:00:00 GMT [source]
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.
Rogue orcas are thriving on the high seas—and they’re eating big whales
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.
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.
Facts about dolphins
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.
Humpback Whales
Some suggest it could be a leftover trait from when whale ancestors were living on land. Others suggest that the nerves around the hair follicles help the whales in some way, and could be used to sense changes in the water such as pressure, helping whales detect shoals of fish or changes in the currents. There is some research showing that Minke whales have been observed using their chin hairs to detect air and ice interfaces in cold Antarctic waters. The bumps on humpback whales’ head, mouth and even on their flippers are called tubercles.
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.
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.
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.
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