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Caaing-whale
The long-finned pilot whale, or pothead whale (''Globicephala melas'') is a large species of oceanic dolphin. It shares the genus ''Pilot whale, Globicephala'' with the short-finned pilot whale (''Globicephala macrorhynchus''). Long-finned pilot whales are known as such because of their unusually long pectoral fins. Taxonomy and naming Etymology Pilot whales get their name from the original belief that there was a "pilot" or lead individual in their groups.Olson, P.A. (2008). "Pilot whale ''Globicephala melas'' and ''G. muerorhynchus''". pp. 847–52 in ''Encyclopedia of Marine Mammals''. Perrin, W. F., Wursig, B., and Thewissen, J. G. M. (eds.). Academic Press; 2nd edition. Ridgway, S. H. (1998). ''Handbook of Marine Mammals: The second book of dolphins and the porpoises''. Volume 6, Elsevier. pp. 245–69. The name for the genus, "''Globicephala''" is derived from a combination of Latin ''globus'' ("globe") and Greek ''kephale'' ("head"). The specific name "''melas''" is Gre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Stewart Traill
Thomas Stewart Traill (29 October 1781 – 30 July 1862) was a British physician, chemist, meteorologist, zoologist and scholar of medical jurisprudence. He was the grandfather of the physicist, meteorologist and geologist Robert Traill Omond FRSE (1858-1914). Early life Traill was born at Kirkwall in Orkney, the son of the Rev Thomas Traill (died 1782), the minister in Kirkwall, and his wife Lucia. His father died the year after he was born. He studied medicine at the University of Edinburgh under Dr Alexander Monro, gaining his doctorate (MD) in 1802. He was elected a Fellow of the Royal Society of Edinburgh in 1819. His proposers were Robert Jameson, John Murray, Lord Murray, and Thomas Charles Hope. He was Curator of the Society's museum from 1834 to 1856. He practised medicine for 30 years in Liverpool, and was a founder of the Royal Institution of Liverpool, the Liverpool Mechanics' Institution and the Literary and Philosophical Society of Liverpool. He became a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Phenotypic trait, Trait inheritance and Molecular genetics, molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the Cell (bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Octopus
An octopus (: octopuses or octopodes) is a soft-bodied, eight-limbed mollusc of the order Octopoda (, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttlefish, and nautiloids. Like other cephalopods, an octopus is bilaterally symmetric with two eyes and a beaked mouth at the centre point of the eight limbs. An octopus can radically deform its shape, enabling it to squeeze through small gaps. They trail their appendages behind them as they swim. The siphon is used for respiration and locomotion (by water jet propulsion). Octopuses have a complex nervous system and excellent sight, and are among the most intelligent and behaviourally diverse invertebrates. Octopuses inhabit various ocean habitats, including coral reefs, pelagic waters, and the seabed; some live in the intertidal zone and others at abyssal depths. Most species grow quickly, mature early, and are short-lived. In most species, the male uses a speciall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squid
A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also called ''squid'' despite not strictly fitting these criteria). Like all other cephalopods, squid have a distinct head, Symmetry (biology)#Bilateral symmetry, bilateral symmetry, and a mantle (mollusc), mantle. They are mainly soft-bodied, like octopuses, but have a small internal skeleton in the form of a rod-like gladius (cephalopod), gladius or pen, made of chitin. Squid diverged from other cephalopods during the Jurassic and occupy a similar Ecological niche, role to teleost fish as open-water predators of similar size and behaviour. They play an important role in the open-water food web. The two long tentacles are used to grab prey and the eight arms to hold and control it. The beak then cuts the food into suitable size chunks for swal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apex Predator
An apex predator, also known as a top predator or superpredator, is a predator at the top of a food chain, without natural predators of its own. Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic levels. Food chains are often far shorter on land, usually limited to being secondary consumers – for example, Gray wolf, wolves prey mostly upon large herbivores (primary consumers), which eat plants (primary producers). The apex predator concept is applied in wildlife management, conservation biology, conservation, and ecotourism. Apex predators have a long evolutionary history, dating at least to the Cambrian period when animals such as ''Anomalocaris'' and ''Timorebestia'' dominated the seas. Humans have for many centuries interacted with other apex predators including the wolf, Bird of prey, birds of prey, and cormorants to hunt game animals, birds, and fish respectively. More recently, humans have started interacting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light. The interval of time between events is called the period. It is the reciprocal of the frequency. For example, if a heart beats at a frequency of 120 times per minute (2 hertz), its period is one half of a second. Special definitions of frequency are used in certain contexts, such as the angular frequency in rotational or cyclical properties, when the rate of angular progress is measured. Spatial frequency is defined for properties that vary or cccur repeatedly in geometry or space. The unit of measurement of frequency in the International System of Units (SI) is the hertz, having the symbol Hz. Definitions and units For cyclical phenomena such as oscillations, waves, or for examp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Continuum (measurement)
Continuum (: continua or continuums) theories or models explain variation as involving gradual quantitative transitions without abrupt changes or discontinuities. In contrast, categorical theories or models explain variation using qualitatively different states. In physics In physics, for example, the space-time continuum model describes space and time as part of the same continuum rather than as separate entities. A spectrum in physics, such as the electromagnetic spectrum, is often termed as either continuous (with energy at all wavelengths) or discrete (energy at only certain wavelengths). In contrast, quantum mechanics uses quanta, certain defined amounts (i.e. categorical amounts) which are distinguished from continuous amounts. In mathematics and philosophy A good introduction to the philosophical issues involved is John Lane Bell's essay in the ''Stanford Encyclopedia of Philosophy''. A significant divide is provided by the law of excluded middle. It determ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echo
In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, a building, or the walls of enclosed and empty rooms. Etymology The word ''echo'' derives from the Greek ἠχώ (''ēchō''), itself from ἦχος (''ēchos''), 'sound'. Echo in Greek mythology was a mountain nymph whose ability to speak was cursed, leaving her able only to repeat the last words spoken to her. Nature Some animals, such as cetaceans (dolphins and whales) and bats, use echo for location sensing and navigation, a process known as echolocation. Echoes are also the basis of sonar technology. Acoustic phenomenon Walls or other hard surfaces, such as mountains and privacy fences, reflect acoustic waves. The reason for reflection may be explained as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Echolocation
Echolocation, also called bio sonar, is a biological active sonar used by several animal groups, both in the air and underwater. Echolocating animals emit calls and listen to the Echo (phenomenon) , echoes of those calls that return from various objects near them. They use these echoes to locate and identify the objects. Echolocation is used for animal navigation , navigation, foraging, and predation, hunting prey. Echolocation calls can be Frequency modulation, frequency modulated (FM, varying in pitch during the call) or constant frequency (CF). FM offers precise range discrimination to localize the prey, at the cost of reduced operational range. CF allows both the prey's velocity and its movements to be detected by means of the Doppler effect. FM may be best for close, cluttered environments, while CF may be better in open environments or for hunting while perched. Echolocating animals include mammals, especially odontocetes (toothed whales) and some bat species, and, using s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whale Surfacing Behaviour
Cetacean surfacing behaviour is a grouping of movement types that cetaceans make at the water's surface in addition to breathing. Cetaceans have developed and use surface behaviours for many functions such as display, feeding and communication. All regularly observed members of the order Cetacea, including whales, dolphins and porpoises, show a range of surfacing behaviours. Cetacea is usually split into two suborders, Odontoceti and Mysticeti, based on the presence of teeth or baleen plates in adults respectively. However, when considering behaviour, Cetacea can be split into whales (cetaceans more than 10 m long such as sperm and most baleen whales) and dolphins and porpoises (all Odontocetes less than 10 m long including orca tp://ftp.fao.org/docrep/fao/009/t0725e/t0725e10.pdf FAO Marine Mammals of the World, Suborder Odontoceti.) as many behaviours are correlated with size. Although some behaviours such as spyhopping, logging and lobtailing occur in both groups, others such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
