Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of the processes involved is called tribology, and has a history of more than 2000 years.
The wild turkey is an upland game bird native to North America, one of two extant species of turkey and the heaviest member of the order Galliformes. It is the ancestor to the domestic turkey, which was originally derived from a southern Mexican subspecies of wild turkey.
The erhu is a Chinese two-stringed bowed musical instrument, more specifically a spike fiddle, which may also be called a southern fiddle, and is sometimes known in the Western world as the Chinese violin or a Chinese two-stringed fiddle.
The ocellated turkey is a species of turkey residing primarily in the Yucatán Peninsula, Mexico, as well as in parts of Belize and Guatemala. A relative of the North American wild turkey, it was sometimes previously considered in a genus of its own (Agriocharis), but the differences between the two turkeys are currently considered too small to justify generic segregation. It is a relatively large bird, at around 70–122 cm (28–48 in) long and an average weight of 3 kg (6.6 lb) in females and 5 kg (11 lb) in males.
A purr or whirr is a tonal fluttering sound made by some species of felids, including both larger, outdoor cats and the domestic cat, as well as two species of genets. It varies in loudness and tone among species and in the same animal. In smaller and domestic cats it is known as a purr, while in larger felids, such as the cheetah, it is called a whirr.
A machine head is a geared apparatus for tuning stringed musical instruments by adjusting string tension. Machine heads are used on mandolins, guitars, double basses and others, and are usually located on the instrument's headstock. Other names for guitar tuners include pegs, gears, machines, cranks, knobs, tensioners and tighteners.
Dog communication is the transfer of information between dogs, as well as between dogs and humans. Behaviors associated with dog communication are categorized into visual and vocal. Visual communication includes mouth shape and head position, licking and sniffing, ear and tail positioning, eye gaze, facial expression, and body posture. Dog vocalizations, or auditory communication, can include barks, growls, howls, whines and whimpers, screams, pants and sighs. Dogs also communicate via gustatory communication, utilizing scent and pheromones.
Animal song is not a well-defined term in scientific literature, and the use of the more broadly defined term vocalizations is in more common use. Song generally consists of several successive vocal sounds incorporating multiple syllables. Some sources distinguish between simpler vocalizations, termed “calls”, reserving the term “song” for more complex productions. Song-like productions have been identified in several groups of animals, including cetaceans, avians (birds), anurans (frogs), and humans. Social transmission of song has been found in groups including birds and cetaceans.
Kneading is a behavior frequently observed in domestic cats where, when a cat feels at ease, it may push out and pull in its front paws against a surface such as furniture or carpet, or against another pet or human, often alternating between right and left limbs. Each stroke is accompanied by a grasping motion of the claws as if the cat were kneading dough.
Cats communicate for a variety of reasons, including to show happiness, express anger, solicit attention, and observe potential prey. Additionally, they collaborate, play, and share resources. When cats communicate with humans, they do so to get what they need or want, such as food, water, attention, or play. As such, cat communication methods have been significantly altered by domestication. Studies have shown that domestic cats tend to meow much more than feral cats. They rarely meow to communicate with fellow cats or other animals. Cats can socialize with each other and are known to form "social ladders," where a dominant cat is leading a few lesser cats. This is common in multi-cat households.
The stick–slip phenomenon, also known as the slip–stick phenomenon or simply stick–slip, is a type of motion exhibited by objects in contact sliding over one another. The motion of these objects is usually not perfectly smooth, but rather irregular, with brief accelerations (slips) interrupted by stops (sticks). Stick–slip motion is normally connected to friction, and may generate vibration (noise) or be associated with mechanical wear of the moving objects, and is thus often undesirable in mechanical devices. On the other hand, stick–slip motion can be useful in some situations, such as the movement of a bow across a string to create musical tones in a bowed string instrument.
Cat behavior encompasses the actions and reactions displayed by a cat in response to various stimuli and events. Cat behavior includes body language, elimination habits, aggression, play, communication, hunting, grooming, urine marking, and face rubbing. It varies among individuals, colonies, and breeds.
Prusten is a form of communicative behaviour exhibited by some members of the family Felidae. Prusten is also referred to as chuffing or chuffle. It is described as a short, low intensity, non-threatening vocalization. In order to vocalize a chuff, the animal's mouth is closed and air is blown through the nostrils, producing a breathy snort. It is typically accompanied by a head bobbing movement. It is often used between two cats as a greeting, during courtship, or by a mother comforting her cubs. The vocalization is produced by tigers, jaguars, snow leopards, clouded leopards and even polar bears. Prusten has significance in both the fields of evolution and conservation.
The National Wild Turkey Federation is an international non-profit organization whose mission is 'the conservation of the wild turkey and the preservation of our hunting heritage.' It currently has more than 250,000 members in the United States, Canada, Mexico and 14 other countries.
Seismic or vibrational communication is a process of conveying information through mechanical (seismic) vibrations of the substrate. The substrate may be the earth, a plant stem or leaf, the surface of a body of water, a spider's web, a honeycomb, or any of the myriad types of soil substrates. Seismic cues are generally conveyed by surface Rayleigh or bending waves generated through vibrations on the substrate, or acoustical waves that couple with the substrate. Vibrational communication is an ancient sensory modality and it is widespread in the animal kingdom where it has evolved several times independently. It has been reported in mammals, birds, reptiles, amphibians, insects, arachnids, crustaceans and nematode worms. Vibrations and other communication channels are not necessarily mutually exclusive, but can be used in multi-modal communication.
Howling is a vocal form of animal communication seen in most canines, particularly wolves, coyotes, foxes, and dogs, as well as cats and some species of monkeys. Howls are lengthy sustained sounds, loud and audible over long distances, often with some variation in pitch over the length of the sound. Howling is generally used by animals that engage in this behavior to signal their positions to one another, to call the pack to assemble, or to note their territory. The behavior is occasionally copied by humans, and has been noted to have varying degrees of significance in human culture.
A form-fit, form-locking or form-closed connection is a type of mechanical connection between two parts, wherein these parts due to their forms interlock and block each other along at least one defined linear or rotational direction.
