Analysis of Dolphins Aristotle once wrote, “The voice of the dolphin in the air is like that of the human in that they can pronounce vowels and combinations of vowels, but have difficulties with the constants.” The dolphin is one amazing creature. Dolphins, whales and porpoises are all related. I am going to talk about all aspects off the dolphin from evolution and vocalization to behavior and intelligence. Dolphin fossils have been found dating back to 45-50 million years ago, which was during the early Eocene epoch era. The early dolphin or Protosetidae, back then did not resemble today’s dolphin. It is suggested that a primitive mammal called Mesonychidae roamed the planes of Africa. This mammal started to become more dependent on the ocean and swamps abundance of food. Researchers believe the dolphin went through an amphibious stage, similar to the seals. They would feed in the ocean and come upon land to breed. Roughly 30 million years ago the early dolphin split into two main species, the toothed whale and the baleen whale. The group called Delphinidae is where the modern day dolphin arose. These fossils date back to 25 million years ago. Modern day dolphins live in rivers and oceans throughout the world. There are 33 known species of ocean dolphins and five river dolphins. The bottle-nosed dolphin inhibits mainly temperate and tropical waters, in the Pacific, Atlantic, Indian ocean and Mediterranean Sea. They normally stay close to shore in warmer water, but some stay offshore in the cooler waters. Dolphins migrate due to the movement of food supply and the change in water temperature. The size of a dolphin varies from 3.9 feet to 32 feet long and 110 pounds to 18,000 pounds. The tucu... ... middle of paper ... ...tian found that dolphins oculd communicate about abstract ideas. Two dolphins were trained to push different switches to earn a fish. That was simply, but then they had to go in sequence. First one dolphin would hit the switch and then the other dolphin would hit the same switch. Finally, the separated the dolphins so they could only communicate what to do through sound. Dr. Bastian concluded that dolphins can communicate abstract ideas, left and right. Dolphins are amazing animals. Society needs to become more aware of the risks that dolphins face each and every day so my kids, and my kids’ kids can experience dolphins in nature like I have had the chance to. Bibliography: Dolphin Evolution. 3 May 2001. Dolphin Species. 18 May 2001. Donoghue, Michael, and Annie Wheeler. Save the Dolphins. Dobbs Ferry, New York: Sheridan House. 1990
That “prehistoric” whales had the jaw of a wolf (a fifty million year old wolf to be exact) and the ear of a whale. I think that all of our semiaquatic mammals play a big part in the evolution of land mammals to water mammals. Like at some point of say an otter’s life, nature told it to stop evolving so that it wouldn’t become completely marine, but semiaquatic as we named it. How did it know when to stop evolving? Was it changes in the environment? Or the need for survival? Which brings around another question, how did we go from a planet of just rock and magma, to a planet thriving with
One of the most common dolphins that are found in southern California is the bottlenose dolphin (Kelly). The bottlenose dolphin is mainly found in coastal waters between 45 degrees north and 45 degrees south, also in Northern Europe waters. It is believed that there are two types of bottlenose dolphin regional wise: oceanic form and coastal form. This species is studied the most by biologists (Jefferson). The coastal population lives in fairly open groups with twenty or less in a pod, some groups are found to contain more in open ocean. It is not uncommon for these species to interact and breed with other species, as would a human interact with other diverse humans. The dolphins feeding behavior is adapted to the availability of resources. They sometimes are known to work together to catch fish from large schools, they also trail behind large fishing boats to catch what falls behind (Leatherwood).
Scientists had some idea to the evolutionary process of whales. “It has always been clear that aquatic cetaceans must have evolved from terrestrial mammals and returned to the water, and the forelimbs of recent cetaceans still have the same general pattern as that of land mammals.” (Walking with Whales) It was known fact that land mammals and whales were related. However, the change from ancient whales to modern whales is drastic.
Have you ever been out on a boat and saw a dolphin and then a squid?Well I have ! and research has shown some very interesting facts about their similarities and differences.If you look they have lots in common but they also have many differences.
Bottlenose dolphins became part of a United States Navy program in 1959 for the purpose of conducting scientific research into their sonar and hydrodynamics in hopes of getting design ideas for submarines, ship hulls and weapons. It was discovered dolphins hear and navigate in the water by using their natural sonar, which happened to be more precise than most fabricated sonar systems. In the mid-sixties, Navy dolphins were used as mail carriers to underwater laboratories in their home of San Diego, California.
Both sharks and dolphins give birth to live young, but sharks don 't care for their young while dolphins do. Sharks breathe using gills and flow-through breathing while dolphins breathe through a blowhole. One of the most noticeable differences between sharks and dolphins is sharks have vertical tail fins where dolphins have horizontal tail flukes. Dolphins are warm blooded and regulate their body temperature, where sharks are cold-blooded and their body temperature vary with their environment. Sharks have multiple rows of teeth which are constantly replaced throughout their life while dolphins have only a single row of teeth. Sharks are solitary hunters while dolphins are very social creatures and forage and hunt
The origin of modern day whales, a mystery that has puzzled paleontologists for years, may have just been solved with the discovery of an ankle bone. This discovery might sound simple and unimportant, but the bones of these ancient animals hold many unanswered questions and provide solid proof of origin and behavior. The relationship between whales and other animals has proven to be difficult because whales are warm-blooded, like humans, yet they live in the sea. The fact that they are warm-blooded suggests that they are related to some type of land animal. However, the questions of exactly which animal, and how whales evolved from land to water, have remained unanswered until now.
The diet of the Bottlenose Dolphin varies depending on geographical location and even water depth. Bottlenose Dolphins that live inshore will typically feed on fish and other invertebrates that are found near the shoreline (Reynolds). On the other hand deep-water Bottlenose Dolphins feed on squid and fish (Reynolds). Bottlenose dolphins along the U.S. Atlantic Coast typically feed on the following: Atlantic croacker, spot fish, and silver perch (Reynolds). Bottlenose dolphins typically choose prey between 5 and 30 cm in length; adult bottlenose dolphins eat approximately 4% to 6% of their body weight in food per day, while a nursing mother's daily intake is about 8% their weight. (Reynolds; "Diet & Eating Habits"). Although Dolphins do seem to show preferences for certain foods, they lack a sense of smell and do not have taste organs (Cozzi 344). Food is ingested whole rather than being chewed, which indicates that food preferences are not determined by “conventional” senses (Cozzi 344). Dolphins use their sharp teeth to grasp prey, rather than chew, and the tongue to maneuver prey down the throat whole (Jenkins). Although they don’t chew food, they may break up their prey by shaking it in the air and
The second part of the theory involves a more scientific approach. It involves echolocation (echolocation: a high-pitched sound sent out by the dolphin that bounces off an object and returns to the whale. The dolphin interprets the returning echo to determine the object’s shape, direction, distance, and texture). (http://www.zoomdinasaurs.com/subjects/whales/glossary/Echolocation.shtml ) Some say that the dolphins’ use of sonar and echolocation produce changes in the body tissue and cell structure of patients who associate with them. Others believe that sound waves emitted by the dolphins in communication and echolocation stimulate healing. (http://www.idw.org/healing.html) A diminishing of anxiety and depression, enhanced learning in handicapped children, and pain relief are all attributed, by some researchers, to dolphin echolocation (http://www.interspecies.org/dolphin.human/research ). Echolocation is also thought to help increase attention span, develop motor skills, and develop better co-ordination in children (http://www.ulst.ac.uk/papa/dolphin.html).
Whales are believed to have come from land ancestors. The traditional theory of Cetacean evolution was that whales were related to Mesonychids, and extinct order of carnivorous animals (hoofed animals), which resembled wolves with hooves and sister group of the artiodactyls (even-toed animals). These animals had unusual triangular teeth similar to those of whales. This is why scientists long believed that whales evolved from a form of Mesonychid. More recent molecular phylogeny data suggest that whales are more closely related to the artiodactyls, specifically the hippopotamus. The strong evidence for a clade combining cetaceans and artiodactyls is further discussed in the article “Cetartiodactyla”. However, the anthracothere ancestors of hippos do not appear in the fossil record until millions of years after Pakicetus, the first known whale ancestor(Strauss, no date).
Dolphins are highly intelligent mammals that encompass the world. A part of the Odontoceti a parvorder of the infraorder Cetacea, they are related to orcas, beluga and pilot whales. A majority of dolphins live in salt water and are considered oceanic dolphins which tend to congregate in shallow waters of the continental shelf but, there are a handful of species that have been known to thrive in freshwater and can be spotted in rivers. Being carnivores, they can be spotted hunting for squid and various species of fish using their melon for echolocation. Since dolphins are mammals, they give birth to live young, usually one calf, and nurse with their mammary glands. Moments after the calf is born the mom must help guide it to the surface so the
Have you ever thought of animals that don't walk on all fours, or that breathe water? Dolphins are one of the earth's smartest creatures, they are a diverse group of aquatic mammals. Little does anyone know, Japan has been annually slaughtering dolphins in a cove, separating them in different sections.Until The Cove came out in 2009 showing what the fishermen in Taiji do, no one ever knew about these heaps of executions. The question is, is it fair or is it barbaric?
Since the populations in these river systems are separated by hundreds of kilometers of landmass, dispersal between the river systems and contemporary genetic exchange is deemed very unlikely and although these dolphins are occasionally sighted in brackish water, their dispersal between river systems through the ocean would involve a highly improbable journey through exposed saline waters, of at least 4,600 km around the Indian peninsula (Braulik,
...r. Even though they live in the ocean all their life and also amusement parks, dolphins are mammals, not fish. That makes them very intersting animals because of all the charactics that they have that people would have never known about. Dolphins are by far the most intelligant marine mammals in the ocean.
There are thirty-two different species of oceanic dolphins and five different species of river dolphins. River dolphins live in Ganges River, Chinese River, Amazon River, and the Indus River ("Dolphins." -and-more.com). There are only four species of river dolphin alive because one is extinct. These dolphins don't only live in rivers, they also live in lakes and estuaries. Some of the river dolphins are the Pink River dolphin, Indus River dolphin, and the Baiji dolphin (www.a-z-animals.com).