Porpoises, belonging to the genus Phocaenidae, are close relatives of dolphins. One of their unique characteristics that differ from other species of the same order is that they can produce clicks for echolocation at frequencies inaudible to humans. The reason for this is majorly influenced by the Orca, also known as the killer whale. Also, while at first glance dolphins and porpoises look of the same species, they actually are classified into two different geni. Part of this separate taxonomy is due to their many different yet unnoticeable mental and physical characteristics. These two distinct creatures also share a long line of ancestry. Biologists know this because of many found fossils of transitional aquatic mammals.
There are many physical differences between porpoises and dolphins. Porpoises, which are smaller and darker, have flat spade-shaped teeth whereas dolphins have sharper cone-shaped ones. A more observable feature is their triangular dorsal fin compared to the curved wave-like one of most dolphins. They also have a blunt and smaller "beak" (rostrum) than the known bottlenose of some dolphins. Lastly, they live in a deeper and cooler location.This is their most important difference because it explains the evolutionary changes of most of the characteristics listed. They evolved to accommodate for their new
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environment. Porpoises have an ability similar to that of dolphins called echolocation.
Echolocation is when an organism determines the location of something by measuring the time it takes for an echo to return from it. Porpoises unlike dolphins produce clicks at frequencies greater than 100kHz. This in theory resulted from a selective pressure imposed by their biggest predator, the killer whale, which has a maximum hearing limit of 100kHz (Tabor, paragraph 3-4). Porpoises usually travel solely or in groups of 4, therefore they would not provide enough defense against them. They instead developed this high click strategy to disregard them completely. Dolphins
on Fig. 6 Odontoceti Divergence the other hand travel in large groups, therefore having the ability to work together and drive off these predators. They also developed incredible speeds to escape them when necessary. Porpoises come from the order Cetacea which includes dolphins and whales. All these organisms originated from the oldest prehistoric whales called the Archaeoceti. These differed from modern cetaceans in three main ways: one was that they had different sets of teeth in separate areas of the mouth; two was that they had nostrils at the tips of their rostra; three was that they had hind limbs outside of their bodies (UCMP, paragraph 5). They then evolved into two paths: the Odontoceti and the Mysticeti. The Odontoceti contains the toothed whales and the Mysticeti contains the filter-feeding whales. Over time each path diverged into more paths and during the Miocene epoch, Odontoceti split into Delphinidae and Phocaenidae, aka dolphins and porpoises respectively. This most likely occurred from natural selection taking place at different depths of the ocean. There are many major reasons for the taxonomical distinction and evolutionary separation of porpoises from other cetaceans. Porpoises received high-frequency echolocational clicks because of killer whales. Due to different environments, their ancestral tree diverged into many branches of geni including theirs. Somehow they have managed to stay on the same large branch as dolphins yet still be on opposite sides because of all their differences. Porpoises have come a long way and will continue to split into whole new species for years to come.
No i believe that orcas should not be kept in captivity There are 3 reasons why they should not, firstly orcas mistreat each others, second you can’t recreate their environment, and lastly orcas can be dangerous in captivity.
Dolphins make up the largest and most diverse family of cetaceans. The family contains 26 recognized species of which 13 tend to have long well defined beaks and streamlined robust bodies. Many vary in size, shape, colors, beaks and flippers, as humans have various characteristics.
Orca whales do not like to be taken from their family, held captive for many decades and put with other whales that they do not know. No other living organism on this planet would like to be put through the same thing. Orca whales are highly social animals, they are very intelligent, and are very emotional. If they are kept away from other whales, fed intermittently and received little attention from staff makes them get very emotional and can lead to death of people and the whales. Orca whales should not be held captive; they are beautiful creatures that are not great for people’s amusement and if they are treated poorly, they will act poorly.
Sarai Michel English 9HP, Period 4 When I was six years old, my parents took me to SeaWorld for the first time. I remember clearly watching the Shamu show and sitting in the splash zone, ending up soaked in water by the end. But I also distinctly remember wondering how an animal so big and beautiful could ever be happy in such a small tank, so far away from home. The animals could never possibly experience the joy they would have out in the wild where they belonged.
Killer whales are one of the most fascinating displays of ocean life. The killer whale has characteristics that are important to its survival in the ocean. It is interesting to know that killer whales have a plentiful diet. It is astounding to see how killer whales behave in the ocean. I plan to tell you about the killer whale, its characteristics, its diet, and its behavior in the ocean as well as the predation of the orca.
Killer whales communicate by a series of clicks and whistles called vocalization. Each pod, or family, has their own unique language. This gives whales the ability to identify their own pods. Orcas have a brain that is about five ti...
Shirihai, H. and B. Jarrett (2006). Whales, Dolphins and Other Marine Mammals of the World. Princeton, Princeton University Press. p.185-188.
These whale songs can be heard by humans because Humpback whales usually swim near the coast and sing with a strong voice. Whale songs can be heard in 30 kilometres’ distance.
Penguins and Orcas are different because penguins huddle in groups to stay warm and the orcas don't because they just stay warm by themselves and because they don't travel in groups. On the other hand penguins are apart of the bird family unlike orcas who are apart of the sea. In other words orcas have rubbery skin and penguins have scale like feathers. Orcas use spyhopping to find their dinner while penguins use their beak/nose. As well as penguins
An orca, more commonly known as a killer whale, is currently one of the largest marine animals held in captivity. Countless arguments are being made, supporting and opposing captivity of orcas to be exploited as circus animals in theme parks around the world. Throughout recent history, Sea World trainers have been injured and killed by the orcas and the whales, and the whales themselves have been observed as severely depressed. If Sea World releases the whales, they would undergo an immense economic downfall and the whales would be too weak to survive in the wild if they were freed. Since the first Sea World park opened in San Diego, California in 1964, common questions have arose concerning the well-being of orcas in captivity, the dangers of humans training them, the physical capability of whales theoretically being released, and the psychological differences between whales living in the wild versus whales living in Sea World's confinement.
Orcas have fusiform bodies, meaning that they are spindle-shaped. This allows them to glide through the water with very little resistance. The male and female orca are different in terms of their size, weight, and the shape of both their dorsal and pectoral fins. Males generally range from 22 to 27 feet in length, weighing between 8,000 and 12,000 pounds. Females generally range from 17 to 24 feet in length, weighing between 3,000 and 8,000 bounds. A male’s pectoral fins, dorsal fins, and flukes grow larger than a female’s grow, making it easy to distinguish the sexes of the species. Orcas are easily recognizable due to the coloration. While mostly black in coloration, the area behind the dorsal fin is tinted gray,
The Humpback Whale, Megaptera novaeangliae, is part of the marine mammals group. They are found in oceans all over the world, they live in open waters. Even though they are mammals, they do not live on land (Monterey Bay Aquarium). Humpback whales are known for their magical song that can travel great distances. These gentle giants are omnivores, their main diet is krill. They are mostly found near coastlines feeding on tiny shrimp-like krill, plankton and small fish. Humpbacks migrate annually from summer feeding grounds near the poles to warmer winter breeding water closer to the Equator. Humpback whales are powerful swimmers, and they use their massive tail fin, called a fluke to propel themselves through or even out of the water! Mothers and their young swim close together, often touching one another with their flippers with what appears to be gestures of affection. Even though it takes more than one year for a humpback whale to grow fully, mother whales leave them after one year (National Geographic).
Whales have special adaptations which help them survive in the water. I have already mentioned blubber and bones in their flippers, but there are more. Echolocation is a whale's navigation tool to help them get around in the water, find food, and potential threats. By using echolocation toothed whales can determine many factors about their environment such as how far an object is, how fast it is moving, whether it is above or below them, what direction it is traveling in, how large it is and whether it is a hollow or solid object. It is extremely useful in areas where visibility is low and helps whales avoid colliding with other objects when they are unable to see what is around them. Their lungs are also very important. Their lungs are able to exchange as much as 90% of the oxygen they inhale as compared to an average human's lungs which can only
There are many reasons why dolphins are very intelligent animals, there are 33 different types of marine dolphins, 4 types of river dolphins, and 6 types of porpoises (dolphins are mammals). Some of the dolphinspeople may think they would be whales, because of their looks, but they are dolphins. Dolphins have a strong behavior; they are very social and travel in groups together. They commonly swim in groups of 2-15 . Severalof different groups of dolphins may temporarily join, for several minutes or hours. In the open waters of theocean, some dolphins will leave their group and change associates and adapt with different dolphins threw outtime (Dolphins communication). In the groups, some members will form a strong bond with one another in thepod. The sizes of the groups tend to increase with the water depth of the ocean and the openness of the habitat, this usually happens when protection with strong with each other and foraging st...