notably, whiskers provide important information about the movement of prey, kittens, and other social partners immediately adjacent to the cat. Touch becomes the primary sense at close range due to poor visual acuity at this distance (Bradshaw et al. 2012). The cat’s canine teeth and claws also have pressure receptors to aid in preventing the escape of prey once captured (Byers and Dong 1989).
At rest cat facial whiskers are positioned slightly backward, but when moving or aroused, whiskers move forward and away from the head to prepare for gathering information (Beaver 2003). Therefore, whisker position can be a form of conspecific visual communication as well.
2.4 Communication
2.4.1 Vocalization
Conspecific vocal communication is only heard during agonistic, sexual, or mother‐kitten encounters (Kiley‐Worthington 1984). Cats vocalize much more frequently to humans, primarily through the open‐mouthed meow (or miaow) sound, which functions as attention seeking with a learned component. Close‐range affiliative communications include the purr and the trill. The purr is a care‐soliciting behavior heard from kittens when nursing, during friendly interactions, or when the cat is mildly anxious or ill (Crowell‐Davis et al. 2004; Overall 2013). The chirr or trill is a modified, mostly closed‐mouth meow sound used in greeting. The estrus call is also a closed‐mouth vocalization heard from females during courtship and can be similar in character to a type of agonistic male cat call (Overall 2013; Wolski 1982). However, aggressive intercat vocalizations are usually open‐mouthed and include the hiss, spit, growl, snarl, growl, yowl, and shriek (Crowell‐Davis et al. 2004).
2.4.2 Scent
Urination, defecation, and scratching are behaviors used to disseminate olfactory information (Brown and Bradshaw 2013). Urine, feces, and sebaceous glands, predominantly located on the head, perianal area, and between the digits of the paws, are rich in information about an individual and, therefore, effective forms of olfactory communication. Head rubbing of objects or social targets leaves olfactory signals from sebaceous glands located on the temporal region of the head, under the chin, and around the lips. This head bunting behavior is often accompanied by purring (Crowell‐Davis et al. 2004). Pheromones have been identified from the cheek sebaceous glands (Pageat and Gaultier 2003) and are thought to be a form of conspecific social signaling.
2.4.3 Visual Signals
Body postures and facial expressions communicate intent and emotional state at a particular moment. Specific behaviors and body positions can have multiple meanings; thus, assessing the entire body, other signals (e.g., vocalizations), and the context is critical when humans are trying to interpret a cat’s emotional state.
The vertical “tail up” is one of the most important visual signals (see Figure 2.1). It largely signals the desire to interact amicably. The cat receiving a “tail up” signal may reciprocate with an approach, followed by touching noses; rubbing of the head, neck, and body along the body of another cat; and tail twining (Cafazzo and Natoli 2009). A similar approach and rubbing behavior sequence may be displayed toward an individual of another species, especially human, or an object near the intended receiver (Turner 2017). A stiff, lashing tail indicates aggression, and a tail tucked under the body signifies fear in a non‐resting cat. Piloerection, or hairs stiffened and standing away from the body, indicates strong arousal and is usually accompanied by an upright or arched body, but the tail may be erect or low. A tail wrapped around the body of a sitting cat is thought to communicate ambivalence—the cat is unlikely to show aggression but is not enthusiastic about the interaction (Leyhausen 1979).
Figure 2.1 Tail up greeting display.
Source: Reproduced with permission from N. Drain. © Natasha Drain.
Facial expressions are associated with a range of emotions. A distressed cat’s eyes may blink and pupils dilate, ears lower or flatten to the head, and whiskers move forward. These expressions may be accompanied by hissing or other defensive vocalizations (see Figure 2.2). A very relaxed cat is often lying lateral with the eyes, pupils, and ears in a neutral position. A cat resting in a sternal or sphinx‐like position, often with the tail wrapped around the body, may be slightly more anxious or vigilant about the surroundings (Leyhausen 1979; Bennett et al. 2017; Gourkow et al. 2014).
Figure 2.2 Defensive position.
Source: Reproduced with permission from K. Watts. © Katie Watts.
General Appendix B describes common feline body language characteristics.
2.5 Behavioral Development
As a species, cats are extremely adaptable to various environments, but the degree of plasticity is determined by a combination of genetics, prenatal environment, and postnatal experiences, especially those occurring during the socialization development period. Born blind, deaf, and completely dependent on the queen for nourishment, the neurological, musculoskeletal, and cognitive maturation of a kitten from birth to adulthood is a short but complex process.
2.5.1 Genetics
Comparative genetics studies have revealed the domestic cat varies from wildcats at 13 chromosomal loci, many of which code for genes related to neurodevelopment or neurotransmitters known to affect various emotional or motivational states, perhaps revealing the genetic basis for tameness (Montague et al. 2014). Humans have a long history of enhancing certain traits through genetic selection, and this is most evident in the domestic dog, the species with the greatest morphologic diversity on earth. Humans have a much shorter history of selectively breeding domestic cats, and the primary objective has been advancement of desired physical, not functional, traits. Nevertheless, consistent breed predispositions for certain behavioral characteristics seem to exist. Several observational and survey studies have identified differences among purebred cats in terms of aggression, propensity to elimination outside the litterbox, playfulness, shyness, and activity level (Mendl and Harcourt 2000; Wilhelmy et al. 2016; Salonen et al. 2019). Many people believe that coat color and certain personality traits are linked. For example, calico or tortoiseshell color cats are often thought to be more aggressive and anxious (Stelow et al. 2015). While the owner‐queried survey results of Stelow et al. (2015) did indicate some minor increases in aggressive behavior within sex‐linked orange color cats, Wilhelmy et al. (2016) found that differences in behavior among purebred cat coat colors were largely explained by breed alone.
Cat personalities seem to be stable and vary along several dimensions of confidence, nervousness, sociability, and activity (Lowe and Bradshaw 2001; Karsten et al. 2017; Litchfield et al. 2017). Personality, like most behavioral phenotypes, is a confluence of environmental and genetic influences. Kittens sired by males with outgoing and friendly personalities were found to show more approach and affiliative behaviors to people, be less stressed by the approach of unfamiliar people, and be more likely to spend time near a novel object (McCune 1995; Reisner et al. 1994). However, handling and socialization provided a protective effect against some fearful and defensive behaviors. Friendly sired but unsocialized kittens behaved in a similar manner to unfriendly sired socialized kittens (McCune 1995).
2.5.2 Sensitive Periods of Development
2.5.2.1 Prenatal