One hypothesis is that, with a noisy ocean surface, a breach may provide a form of communication that can be better dispersed and received by other whales in multiple directions. In fact, it has been observed that the whales breach more often when their associates are further away, at least 2. In addition, if the waters are particularly choppy, a breach may give a large marine mammal the chance to breath in air that is free from spray.
Another reason for Humpback Whales, and Baleen Whales in general, to breach is to remove some pesky hitchhikers. It is not uncommon for Humpback Whales to be riddled with barnacles and lice and, although not harmful to the whale, too many could be annoying so a jump can be a cleansing event. Breaching events have been linked to communication, with social species jumping more frequently. Propositions include aggression, annoyance, vigor of a male, and courtship behavior.
A jump can also be used to add emphasis to a signal already made: vocal or visual, indicating a desire or a need. Turning our attention back to Killer Whales, a good time to see them leaping out the water is during a hunt.
Air is times less dense than water and so a jump gives the Killer Whale a good advance on its prey. This high-speed leap is known as porpoising and even once the feeding event is over, jumping can take place as a social form of celebration.
In particular, jumping behavior by young ones in the pod, with no conceivable purpose, may simply be practice for the future. Killer Whales have terrific eyesight both above and below the water so popping its head out could be the animal observing its surroundings, looking for other members of its pod or seeing if there is any food around.
However, for Whales lower down the food chain a breach may actually be a signal that there are predators around rather than a signal where the food is. What we can be pretty certain about is that they do not do it to entertain us humans but for some purpose beneficial to their survival. Its tail is longer and more muscular, too. Animals are what they eat and drink, and saltwater and freshwater have different ratios of oxygen isotopes.
This means that we can learn about what sort of water an animal drank by studying the isotopes that were incorporated into its bones and teeth as it grew. The isotopes show that Ambulocetus likely drank both saltwater and freshwater, which fits perfectly with the idea that these animals lived in estuaries or bays between freshwater and the open ocean.
Whales that evolved after Ambulocetus Kutchicetus , etc. These animals evolved nostrils positioned further and further back along the snout. For example, the pelvis had evolved to be much reduced in size and separate from the backbone. This may reflect the increased use of the whole vertebral column, including the back and tail, in locomotion. To swim, they move their tails up and down, rather than back and forth as fishes do.
This is because whales evolved from walking land mammals whose backbones did not naturally bend side to side, but up and down. You can easily see this if you watch a dog running. Its vertebral column undulates up and down in waves as it moves forward. Whales do the same thing as they swim, showing their ancient terrestrial heritage. As whales began to swim by undulating the whole body, other changes in the skeleton allowed their limbs to be used more for steering than for paddling.
In the skeletons of living dolphins and whales, the transition from body to tail fluke is marked by a change in their vertebral column: body vertebrae are taller than they are wide, and tail fluke vertebrae are wider than they are tall.
We see the same pattern in fossils from early basilosaurid whales, like Dorudon and Basilosaurus , and so know that they had flukes that could help power swimming. They also had other skeletal changes that accommodate an aquatic lifestyle.
Their elbow joints were flexible, unlike living whales, but able to lock, allowing the forelimb to serve as a better control surface and resist the oncoming flow of water as the animal propelled itself forward. The hindlimbs of these animals were almost nonexistent. This pattern is often called cat-napping. Dolphins generally sleep at night, but only for a couple hours at a time; they are often active late at night, possibly matching this alert period to feed on fish or squid, which then rise from the depths.
Bottlenose dolphins, based on electroencephalogram EEG readings, spend an average of It is not clear whether cetaceans undergo dream sleep.
But a pilot whale was noted as having six minutes of REM in a single night. To avoid drowning during sleep, it is crucial that marine mammals retain control of their blowhole. The blowhole is a flap of skin that is thought to open and close under the voluntary control of the animal.
Although still a matter of discussion, most researchers feel that in order to breathe, a dolphin or whale must be conscious and alert to recognize that its blowhole is at the surface. Humans, of course, can breathe while the conscious mind is asleep; our subconscious mechanisms have control of this involuntary system.
But equipped with a voluntary respiratory system, whales and dolphins must keep part of the brain alert to trigger each breath. Other methods help marine mammals to hold their breath longer than other types of mammals can.
Marine mammals can take in more air with each breath, as their lungs are proportionately larger than those in humans. In addition, they exchange more air with each inhalation and exhalation. Their red blood cells also carry more oxygen. And when diving, marine mammals' blood travels only to the parts of the body that need oxygen--the heart, the brain and the swimming muscles. 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. The narwhal tusk is the only animal horn or tusk with such unique anatomy.
All marine mammals in U. Protecting cetaceans in international waters is more difficult. With an international ban on whaling in effect since allowing for some exceptions many whale populations have bounced back from low numbers. However, several species populations remain extremely low.
In early , fewer than individual North Atlantic right whales remain and they are considered critically endangered, as are their sister species, North Pacific right whales , with fewer than individuals remaining. The vaquita, a small porpoise found only in coastal waters of the Gulf of California off of the Baja Peninsula in Mexico is also extremely endangered, mostly because of getting caught accidentally in fishing gear.
There are now less than 20 of these porpoises left. One of the biggest threats to whale survival is entanglement from fishing gear. Once made with biodegradable wood and ropes, fishing gear is now predominantly made of synthetic materials, like plastic. Today, female right whales are giving birth every 9 years as opposed to every three years as they were in the s, a trend that is likely not only influenced by entanglement but other stressors as well.
Consumption of plastic debris can also kill whales. Not only can the whales die from blockage of their stomach or intestines, sharp plastic shards can also pierce intestinal lining, and they can starve due to feeling falsely full from a stomach full of plastic with no nutrients.
As filter feeders, baleen whales suck in large volumes of water to catch the fish and krill required to sustain their massive sizes, and discriminating between food and plastic is impossible. Toothed whales can also unknowingly consume plastic hidden within their prey.
In , a large sperm whale was found beached with over pounds of trash in its stomach. Right whales live and migrate along coastal shores and so they frequently pass and congregate near bustling ports.
They are also slow swimmers, a trait that has proven deadly in the 21st century. Between and , 45 North Atlantic right whales were found dead in coastal waters of the U. Other whales, like the fin whale, blue whale, and humpback whale, are also struck by passing ships.
A study of humpback whales that live off the Gulf of Maine found that 15 percent of humpback whales in the region have injuries related to ship strikes. These findings prompted negotiations between the New England Aquarium, the National Marine Fisheries Service, the International Maritime Organization, and the shipping industry to move shipping lanes away from known whale congregation areas and to decrease ship speed limits. In , United States regulations were modified to limit the speed of larger ships to 10 knots 11 miles per hour when at a distance of 20 nautical miles 23 miles offshore during whale calving season, a time that changes according to the location along the coast.
It seems as though the rule is limiting whale death caused by ship strikes. Between and only two right whales were killed by ship strikes within U. Comparatively, ships killed 15 right whales between and , and 13 of those were found in areas now protected by speed limits. Unfortunately, although this effort has reduced deaths caused by ship strikes, the right whale population continues to decline due to gear entanglements.
As humans continue to increase their presence at sea, it becomes a noisier place to live. Ship and submarine sonar pings, military tests and drills, seismic testing, the churning of boat motors, and drilling on oil rigs are just a sample of manmade noises that contribute to noise pollution in the ocean. Whales rely heavily on sound for communication, but in this new noisy reality they struggle to have their voices heard.
Whale behavior is also harmed by the presence of human noise. Beluga whales were observed vacating a feeding area and swimming 50 miles 80 km away for several days to avoid an approaching ice-breaker ship. Beaked whales and blue whales are particularly sensitive to sonar, and several mass strandings have been tied to related military exercises. But there is cause to be hopeful. In an effort to reduce the impact of sonar on whales, the U.
Navy agreed in to end mid-frequency sonar training in specified areas where whales congregate, and in they extended the exclusion to low-frequency hunting sonar. In waters near British Columbia, Canada, a voluntary speed reduction policy during the season when endangered orcas migrate through Haro Strait was put in place for the first time in The initial policy successfully decreased noise pollution from commercial ships and was continued in This work includes completely protecting certain species, designating sanctuary areas, setting catch limits for specific species, deciding on appropriate whaling seasons, and prohibiting the capture of mothers with their calves.
But as whaling populations continued to decline, the Commission evolved to fill a conservation role. In , the IWC officially banned commercial whaling, however, aboriginal whaling and the issuance of scientific whaling permits are still allowed.
Because of these efforts, in most humpback whale populations were removed from the endangered species list. Only the population that breeds in Central America remains on the list, and the California blue whale population is also making a comeback.
In , a study determined that this subset of blue whales is at about 97 percent of what it was prior to whaling , offering hope that other whale species and populations, with continued protection, can rebound. Since , whales have found a home at the Smithsonian Institution. At that time Spencer Fullerton Baird was a curator and avid naturalist who made whale research a top priority for the Institution.
Fish and Wildlife Service. 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 While Baird was at the Museum he acquired many marine mammal specimens, including those from the U.
Exploring Expedition of to The museum is also home to Phoenix, a 45 foot, 2, pound full-scale model of a female North Atlantic right whale that hangs in the Sant Ocean Hall.
She is one of many whale models that have graced the halls of the Museum, including the blue whale that was the first-ever cast of a whale , and the blue whale that replaced it. Today, the National Museum of Natural History has two curators who specialize in the topic of whales. Nick Pyenson , author of the critically acclaimed Spying on Whales, is a specialist on fossil whales, and Michael McGowen is a whale geneticist.
After the new U. National Museum today the National Museum of Natural History opened in , it was moved across the Mall, mounted on a pedestal, and placed at the center on the Hall of Marine Life. For fifty years the seventy-eight-foot cast of the blue whale enchanted visitors to the Museum.
The blue whale model met its end around , when it was replaced by a new, even bigger blue whale model. In the s the Smithsonian began an institution-wide exhibits modernization program, and many halls of the Natural History building were completely renovated at this time. The new hall dedicated to Life in the Seas was to have as its centerpiece a state-of-the art model of a blue whale in mid-motion. Modeling techniques had advanced considerably in the decades since , and lightweight plastics and fiberglass allowed for a more dynamic posture.
Most whales could only be studied after they had washed up on a beach or at whaling stations after they had been killed and hauled to shore. Scientists could not agree as to whether or not the ventral plates of the mouth expanded when diving or rising, and this issue presented a significant problem in designing the blue whale model.
The foot-long model was suspended thirty feet above the floor and attached to two steel brackets jutting out from the wall. In , a new exhibit label was added, explaining that there was an error with the model. Photographs of living blue whales still did not exist at this time, but there were a few photographs of other rorquals or baleen whales, including sei and minke whales, that revealed much slimmer, streamlined bodies than expected.
The blue whale model was eventually removed in as renovations began for the new Kenneth E. Behring Family Hall of Mammals. Currently suspended at the center of the Sant Ocean Hall is a life-size model of a North Atlantic right whale named Phoenix.
The result of four years of work, and collaboration between exhibit fabricators, whale biologists, sculptors, painters, engineers, and many others, this exhibit is unique and exciting in that it represents a live animal. Phoenix has been tracked in her Atlantic Ocean environment by marine biologists at the New England Aquarium in Boston, ever since her birth off the coast of Georgia in She is the mother of three calves and became a grandmother in She got her name Phoenix from her ability to rise again, like the mythical bird, after a life-threatening entanglement with fishing gear in She still bears a scar below her right lip from that encounter, which you can see on the model and which scientists use to help identify her in the waters of the Atlantic.
The exhibit highlighted how traditional Inuit knowledge and scientific research can be combined to reveal new insights about these difficult-to-study whales —and the rapidly changing environment they live in. The exhibit displayed a life size model of a male narwhal, skulls and tusks including a rare double-tusked skull , and intricate Inuit artwork. This is one of the many questions paleobiologist Nick Pyenson is researching at the National Museum of Natural History.
By measuring the skulls of baleen whales throughout evolutionary history he and his colleagues were able to create a timeline of when whales began to grow in size. The hypothesis is that during the Ice Ages krill and other zooplankton that whales consumed started to become more concentrated in their seasonal occurrence than prior to that geologic time.
If concentrated food sources were far apart, it would help to be very big: a large body size not only helps you push through water more efficiently but also increases the capacity to store food for energy. A patchy ocean also means that food is grouped together in a dense area, allowing the whales to efficiently eat up large quantities in one sitting. The Gulf of Panama is a bustling place where tens of thousands of ships cross to pass through the Panama Canal.
It is also a popular breeding ground for whales. Tragically, whales often get hit by passing ships and sometimes the collisions are deadly. But in December , new shipping lanes were implemented with the aim to limit the number of ship-whale collisions. This is the first instance where satellite tags were used in the planning of new shipping lanes, and the hope is that it will limit the number of deadly strikes.
During road construction that started in , paleontologists discovered a rich fossil site containing dozens of whale skeletons, along with the remains of other extinct marine mammals and marine vertebrates. At the site the team documented the remains of ten different kinds of marine vertebrates, including billfishes, seals, aquatic sloths, and several different species of whales.
The skeletons of over 40 individual large baleen whales dominated the site and included an extinct sperm whale and an extinct walrus-like whale Odobenocetops , both of which were previously only known from Peru. A 3D print of one of the most complete fossils from this site now hangs on the wall of the Q?
There are many hidden mysteries in the collections of the National Museum of Natural History. With some tenacity and lots of research, the origins of the mystery collection were discovered and the baleen can be used to answer scientific questions. 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. Skip to main content. Whales Cetacea. Are You An Educator? At Smithsonian Ocean, we have lesson plans, activities, and resources to help you engage your students in the wonders of our oceans.
See Lesson Plans. The fluke from the right whale named Phoenix, as seen in New England Aquarium, photographer Tim Frasier. Andrew Russell, Flickr. Credit: Courtesy of Kait Frasier. An unidentified earplug from the National Museum of Natural History collection.
The light and dark layers come from a build up of keratin and lipids and can be used to estimate whale age. A close up of a grey whale eye. North Atlantic right whales Eubalaena glacialis are big—but they're not the biggest whales. That distinction goes to the blue whale Balaenoptera musculus. Smithsonian Institution. A male sperm whale feeding near the surface. Phoenix is seen skim feeding off the coast of Maine in August Allied Whale, College of the Atlantic.
This family tree shows how the ancestors of whales moved gradually from land to sea. North Atlantic right whales migrate seasonally along the eastern coast of the United States. Adapted from E. New England Aquarium researchers Dr. Courtesy of the New England Aquarium. Bottlenose dolphins are very social animals, and often travel and hunt in groups called pods. A humpback whale breaching in Antarctic waters.
Ari Friedlaender. A right whale opens wide, revealing huge plates of baleen hanging from its upper jaw. A bottlenose dolphin carries a sponge, which it uses as a tool to dig up prey from the seafloor.
Ewa Krzyszczyk, Public Library of Science. Cookie-cutter sharks eat smaller animals like squid whole, but also take large, round cookie-cutter shaped bites out of larger animals, such as tuna, whales, dolphins, and seals which you can see in this picture of an elephant seal.
They suction on to the larger animals and twist around to take a bite of flesh using their lower row of sharp teeth. Jerry Kirkhart.
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