The Evolution Of Whales

Clicks are high-frequency and directional sounds that are used to detect, discriminate and recognize objects in the environment, including potential preys (Caldwell et al., 1990; Janik, 2013). These clicks are used to locate/discriminate an object based on the returning echo, and the system is known as echolocation or biosonar (Griffin, 1958). Bottlenose dolphins produce high-frequency broadband clicks with dominant frequencies generally higher than 50-60kHz (Au, 1993).

First, the article claims that this was calls of the male and female orca whales during courtship ritual. The professor refutes this point by saying that this sound was unlikely to be calls of the orca whales. She states that orca whales usually prefer to swim near the surface of water but submarines leaved the surface and patrol in deep are therefore they cannot detect orca whales' calls truly.

Cetaceans use sound extensively in both communication, hunting, and navigation. However as humanity continues to make use of the ocean we are constantly filling it with equipment that produces high amounts of sound. These devices are starting to have an impact on cetaceans worldwide, from mass strandings often linked to military exercises to area denials caused by busy commercial shipping lanes and seismic surveys. If consideration is not taken towards this problem now it could develop into something that could have degrading effects on cetacean populations in the future.

This partly because the frequency ranges of boats and whales can overlap (Holt et al, 2009). If whale individuals are unable to communicate with other members of their pod, there would be less cohesion when hunting, difficulty in finding a mate, and an overall an increase in stress (Holt et al, 2009). There have also been cases where boat motors have impaired the whales to even detect their prey (Barrett-Lennard et al, 1996). These anthropogenic, background sounds are thought to interfere with communication between individuals by masking the whale's calls, particularly if at specific threshold level (Foote et al, 2004). Ways that whales have been shown to adapt include changing the amplitude and duration of calls (Foote et al, 2004; Holt et al, 2009). As the background sounds increased by one decibel, the amplitude also increased by one

Recent Off-Shore drilling in the United States in the Atlantic Ocean has had a very negative effect on Bottlenose Dolphins. The noise caused from drilling has negatively affected their ability to communicate effectively. Recently off-shore drilling has increased to help create more jobs in America however, the Bottlenose Dolphins have been paying the price. Off-shore drilling creates lots of boat traffic around the drilling areas which interferes with the dolphins ability to communicate through echolocation. However the main interference with dolphins communication has been caused by seismic testing from these boats. Seismic testing is when loud blasts of compressed air are sent deep into the ocean to bounce off the seafloor to test to

Scientists have noticed that these creatures of the ocean can actually communicate with each other and form thoughts. As people are doing research and tests on the animals they have noticed that the dolphins try to communicate and play with the humans as well. However, this has been ignored for some time. Dolphins held in captivity are taught commands through American sign language which the dolphins learn quickly and fairly easily. Although dolphins can comprehend the sign language with ease, the lack of hands makes it impossible for dolphins to communicate back with researchers. Dolphins are more acoustic animals, meaning they have a very strong sense of hearing and are very sensitive to sound. Because of this, dolphins communicate with one another through sonar waves. These unique qualities show that these animals are not meant to be locked and kept away from their natural habitat or killed for no real

Another very interesting thing that I have found out in this essay by Regina Blackstock is a case that occurred in 1962 when some Lockheed Aircraft Corporation scientists erected a barrier across a channel with strong microphones. When the dolphins approached it, clicking noises were heard. The dolphins gathered into a group in nearby shallow

Bottlenose dolphins, Tursiops truncatus (Montagu, 1821), are cosmopolitan marine mammals that have been studied both in wild and in captivity, using diverse techniques. The majority of studies involve social structure dynamics, behavior, communication, ecology, distribution, and anatomy, among others. This thesis is divided in three main sections: developing of a tracking system, that enables the quantification of the position of the animal in the pool; accelerometry, that will permit the analysis of fine detailed behavior; and acoustics, in order to better understand the communication of these animals in different contexts. All sections had the purpose of collecting extensive detailed behavior of captive bottlenose dolphins to: 1) develop

First, the first theory suggests that the strange noises were actually the calls of male and female ocra whales during a courtship ritual. The professor opposes this point by saying that this theory is unlikly to be true. The professor states that Ocra lives in the surface of the ocean, while the submarines are patroling in the deep ocean. So, the ocras' sounds were unlikely to be heard in the submarine. Also, Ocras' sounds could

In his essay, Edgar Allan Poe describes the ideal poem or short story as having three main characteristics. Poetry and short stories should be written using three fundamental ideas length, method, and unity of effect. Poe uses his own work of poetry “The Raven” as an example of these three fundamental ideas.

Humans fish to survive and in doing so they will target specific species leading to overfishing. Sound pollution is causing issues with the wildlife of the ocean in how they communicate and move around. With human interaction comes trash which gets left in the ocean and affects many different species.

It feels like every day, countless news stations, websites, and social media users break the tragic story of yet another mass shooting in the US, a fact that is shared by almost no other developed countries. Clearly there is something anomalous about the U.S., why else would the U.S. be the only country where this regularly happens? The answer lies in one key difference between the United States and other developed countries, its policies on gun control and ownership. The 2nd amendment to the United States Constitution states, essentially, that every US citizen has the right to own guns, and that the United States Government may not infringe upon those rights. The truth of the matter is that controlling American Citizen’s access to firearms is the only solution to the undeniable issue of mass shootings and gun related homicides, a fact that is backed up by the example of several other developed countries, in which guns are controlled and incidents of gun homicide and mass murder are far less common than they are in America. Controlling guns in America is a task that has been halted numerous times by the antiquated constitutional stance on American armament, and is the only sensible option for lessening the atrocious tragedies that are seen so often on U.S. soil.

Beaked whales are whales that use noise to communicate. Any type of unusual noises underwater can cause problems, so if there is a background coming from our equipment then they can't really communicate. You might be thinking, " It should be okay if they can't communicate." Well you are wrong. You see, whales use there communication as a backup if they are in trouble, such as being attacked, or even stuck for that matter.

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.

Cetaceans use echolocation to make sense of their world and has only recently been of concern due to the ability of dolphins to locate objects and discriminate objects based on size, shape, and composition (Akamatsu, Nakaqawa, & Hatakeyama, 1995). Any disturbance in the form of sound pollution could cause these cetaceans to mass strand because they are so dependent on sound as their principal sense (Nowacek et al. 2007). Sound travels very efficiently underwater and so impacted areas can affect thousands of square kilometers out. Most of the sound pollution in the ocean come from underwater explosions caused by sonar, seismic testing caused by oil and gas industries, or underwater sea quakes through natural events. The anthropogenic noises can cause deep-diving populations like beaked whales to be threatened and abandon their habitat and surface rapidly. Exposure to anthropogenic sounds negatively affect deep-diving cetaceans (Cox et al. 2006). There are a number of hypotheses for the injuries in the cetaceans that stranded in areas of sonar exercises like decompression sickness and behavioral