Whales Smithsonian Ocean
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Estimating whale populations before large-scale commercial whaling depleted their numbers in the 19th century is particularly difficult. Scientists use historical whaling records or genetic methods (comparing genetic diversity within current whale populations) to determine past population sizes. Larger species also retain heat because their skin surface area is small compared to the size of their bodies. Smaller species make use of higher metabolism and a counter-current heat exchange system of blood vessels in their flukes and flippers to keep warm. This exchange allows for cold blood in the limbs to move from the animal’s extremities in veins directly along arteries carrying warm blood from the animal’s core, instead of losing heat at the surface of the animal’s skin. Their blood vessels are also able to constrict when an animal is in cold water, reducing the amount of energy needed to pump blood throughout the circulatory system and conserving heat.
At the Smithsonian
Today, the live dolphin trade is illegal in the United States, Mexico, and Europe, however, live dolphins are still captured in other countries to minimize inbreeding among the dolphins already in captivity. The nostrils were believed to have been moved to the top of the head to assist with living in the ocean. Bones with digit like structures can also be found in the whales flippers which appear to have been legs or arms that were once used for walking, fighting or gathering food. This can be seen by observing the curvature of a whales spine which appears to resemble that of a species designed for walking and/or running. The existence of hair may also be a sign of their evolutionary past when their ancestors walked on land.
Functions of Whales’ Hairs
The other group of whales are the toothed whales, which as the name suggests possess teeth rather than baleen plates. Whale calves in some species of toothed whales are born with hair along their snouts and lose it quickly after birth. Marine mammals come in all shapes and sizes, from surfboard-stealing sea otters to giant humpback whales making Fibonacci spirals. However while the former is famously cute and fluffy with thick fur, do whales have hair?
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The hairs are connected to nerves that send signals to the brain, allowing the whale to sense the environment around them. The hair also contains sensory cells that detect vibrations and sound waves, which help whales locate prey, communicate, and navigate through the water. Whereas humans breathe through their nose and mouth, whales have a blowhole on the top of their head—or two in the case of baleen whales. While it’s not the same as the human nose, this is where they breathe in and out.
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Whales belonging to the group known as Mysticeti (baleen whales) have two blowholes, while toothed whales (Odontoceti) have only one. Unlike humans who breathe automatically, whales have active control of when they breathe. Cetaceans have specific control over a muscle called the nasal plug that closes the passageway of the blowhole—it remains closed when they are diving and is opened when they reach the surface. Whales are mammals which means that, like humans and other land mammals, they have three inner ear bones and hair, they breathe air, and the females produce milk through mammary glands and suckle their young. Mammals typically have hair to maintain body heat, but because cetaceans have insulating fat in the form of blubber they are often born with minimal hair that is lost as they grow older.
History & Culture
In the 2002 movie Whale Rider, a young Maori girl follows the path originally set forth for her brother to become tribe leader, using her special connection with Southern right whales to prove that she is worthy. In 2013, the release of the documentary Blackfish, a depiction of orca treatment at Sea World, changed the public’s perception of whales in captivity. Many people became upset by the revelations of the documentary, and attendance at marine parks has since dropped.
Animals
Whales may be large, but their bodies are streamlined to help aid in efficient swimming. Cetacean flukes move vertically through the water (unlike fish that typically move their tails horizontally back and forth). Their flippers (or pectoral fins) are modified forelimbs with an immobile elbow joint and are used mainly for steering, whereas flukes help propel the animals forward.
Exposed In The Everglades: The Bryde's Whale That Wasn't (U.S - National Park Service
Exposed In The Everglades: The Bryde's Whale That Wasn't (U.S.
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Beaked whales suck their prey into their mouths in order to swallow them. Larger toothed whales, like orcas, eat fish and cephalopods, but also sharks and larger marine mammals including sea otters, seals, sea lions and smaller whales. Different populations of orcas tend to make their meal choices based on their locations—salmon in waters off the Pacific Northwest, herring in waters off of Europe and minke whales in waters off Antarctica.
Yes, whales have hairs, but not all whales retain them throughout their lives. These hairs, known as sensory hairs, are present in whales when they are born. The number of hairs found on a whale is relatively small, typically ranging from , depending on the species.
Vibrissae in humpback whales can detect movements in the water, such as the path of nearby fish or the current of the water. These hair follicles also aid in reducing drag on the whales’ flippers during movement. In essence, the hair follicles on whales adapt to their aquatic lifestyle and help them survive in their respective environments. While most species shed this hair as they mature, certain species retain their hair throughout their entire lives. While whales are known to have hair, some other marine mammals also possess this characteristic. Among the many water-dwelling creatures that have hair, three notable examples are harp seals, sea otters, and northern fur seals.
It is also thought that the hairs may have a social function, perhaps being used in social situations, by calves communicating a need to nurse, or perhaps in sexual situations. Scientists with NOAA and the Natural History Museum examine the whale skeleton in the museum's massive whale vault. This specimen is now considered the Rice's whale holotype, meaning it is the specimen all other potential Rice's whales will be compared to. The enterprise first started in California in the 1950s and has continued to grow in popularity. In 2009, the industry generated around 2.1 billion dollars from 13 million whale watchers and supported 13,000 jobs.
Being able to regulate their oxygen levels is particularly important for deep-diving species. Once underwater, “they can then slow down their heart rate, and shunt the oxygenated blood to the areas that they need”—including their brain, heart, and muscles. Fossils of gigantic ancient whales called Basilosaurus were first mistaken for dinosaur fossils, but were later recognized as mammals.
The theory is that some land-living ungulates favored munching on plants at the water’s edge which had the added advantage of allowing them to easily hide from danger in shallow water. Over time their descendants spent more and more time in the water and their bodies became adapted for swimming. Their front legs became flippers and a thick layer of fat called blubber replaced their fur coats to keep them warm and streamlined. Eventually, their tails became bigger and stronger for powerful swimming and their back legs shrunk.
Dolphins use their beak and conical teeth, while porpoises have shorter mouths and squarer teeth, both allowing them to grip their prey—no need to chew. One population of dolphins has learned to cover their beaks with conical sponges to dig up fish hiding on the seafloor, a skill that is passed from mothers down to their offspring. Dolphins will also thrash octopuses at the surface as a way to stun them before they attempt to eat them.
Cetaceans grow quickly after birth—a blue whale calf can grow 100 pounds a day. Although the young grow quickly, it takes years for them to reach sexual and social maturity (ten years in the case of most baleen whales). Most toothed whales feed on one prey item at a time, grabbing it and swallowing it whole. Dolphins and porpoises eat a variety of fish, squid and crustaceans, like crabs and lobsters.
Phoenix was chosen because so much is known about her and her family (her mother’s name is Stumpy). At that time Spencer Fullerton Baird was a curator and avid naturalist who made whale research a top priority for the Institution. In 1871, he convinced Congress to create the Commission of Fish and Fisheries, the precursor to today’s National Marine Fisheries Service and the U.S. The agency was run by Baird himself, in addition to his other duties at the National Museum (what is now the National Museum of Natural History), and later when he was elected as Secretary of the Smithsonian in 1878. While Baird was at the Museum he acquired many marine mammal specimens, including those from the U.S.
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