Sense of smell in the context of "Mirror test"

Primates is an order of mammals, which is further divided into the strepsirrhines, which include lemurs, galagos, and lorisids; and the haplorhines, which include tarsiers and simians (monkeys and apes). Primates arose 74–63 million years ago first from small terrestrial mammals, which adapted for life in tropical forests: many primate characteristics represent adaptations to the challenging environment among tree tops, including large brain sizes, binocular vision, color vision, vocalizations, shoulder girdles allowing a large degree of movement in the upper limbs, and opposable thumbs (in most but not all) that enable better grasping and dexterity. Primates range in size from Madame Berthe's mouse lemur, which weighs 30 g (1 oz), to the eastern gorilla, weighing over 200 kg (440 lb). There are 376–524 species of living primates, depending on which classification is used. New primate species continue to be discovered: over 25 species were described in the 2000s, 36 in the 2010s, and six in the 2020s.

Primates have large brains (relative to body size) compared to other mammals, as well as an increased reliance on visual acuity at the expense of the sense of smell, which is the dominant sensory system in most mammals. These features are more developed in monkeys and apes, and noticeably less so in lorises and lemurs. Some primates, including gorillas, humans and baboons, are primarily ground-dwelling rather than arboreal, but all species have adaptations for climbing trees. Arboreal locomotion techniques used include leaping from tree to tree and swinging between branches of trees (brachiation); terrestrial locomotion techniques include walking on two hindlimbs (bipedalism) and modified walking on four limbs (quadrupedalism) via knuckle-walking.

Perception (from Latin perceptio 'gathering, receiving') is the organization, identification, and interpretation of sensory information, in order to represent and understand the presented information or environment. All perception involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sensory system. Vision involves light striking the retina of the eye; smell is mediated by odor molecules; and hearing involves pressure waves.

Perception is not only the passive receipt of these signals, but it is also shaped by the recipient's learning, memory, expectation, and attention. Sensory input is a process that transforms this low-level information to higher-level information (e.g., extracts shapes for object recognition). The following process connects a person's concepts and expectations (or knowledge) with restorative and selective mechanisms, such as attention, that influence perception.

A meow or miaow is a cat vocalization. Meows may have diverse tones in terms of their sound, and what is heard can vary from being chattered to calls, murmurs, and whispers. Adult cats rarely meow to each other. Thus, an adult cat meowing to human beings is generally considered a post-domestication extension of meowing by kittens: a call for attention. Felines usually communicate with each other via their shared sense of smell, yet with people they often make verbal cues around behavior, such as having a specific sound indicate a desire to go outside.

A mew is a high-pitched meow often produced by kittens. It is apparently used to solicit attention from the kitten's mother, and adult cats may use it as well. The mew is similar to what is described in Brown et al. 1978 as an isolation call. By around three to four weeks of age, kittens do not mew when at least one littermate is present, and at four to five months of age, kittens stop mewing altogether.

The olfactory system is the sensory system used for the sense of smell (olfaction). Olfaction is one of the special senses directly associated with specific organs. Most mammals and reptiles have a main olfactory system and an accessory olfactory system. The main olfactory system detects airborne substances, while the accessory system senses fluid-phase stimuli.

The senses of smell and taste (gustatory system) are often referred to together as the chemosensory system, because they both give the brain information about the chemical composition of objects through a process called transduction.

The cat (Felis catus), also referred to as the domestic cat, is a small carnivorous mammal. It is an obligate carnivore, requiring a predominantly meat-based diet. Its retractable claws are adapted to killing small prey species such as mice and rats. It has a strong, flexible body, quick reflexes, and sharp teeth, and its night vision and sense of smell are well developed. It is a social species, but a solitary hunter and a crepuscular predator.Cat communication includes meowing, purring, trilling, hissing, growling, grunting, and body language. It can hear sounds too faint or too high in frequency for human ears, such as those made by small mammals. It secretes and perceives pheromones. Cat intelligence is evident in its ability to adapt, learn through observation, and solve problems. Female domestic cats can have kittens from spring to late autumn in temperate zones and throughout the year in equatorial regions, with litter sizes often ranging from two to five kittens.

The domestic cat is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the domestication of the cat started in the Near East around 7500 BCE. Today, the domestic cat occurs across the globe and is valued by humans for companionship and its ability to kill vermin. It is commonly kept as a pet, working cat, and pedigreed cat shown at cat fancy events. Out of the estimated 600 million domestic cats worldwide, 400 million reside in Asia, including 58 million in China. The United States leads in cat ownership with 73.8 million cats, followed by the United Kingdom with approximately 10.9 million cats. It also ranges freely as a feral cat, avoiding human contact. Pet abandonment contributes to increasing of the global feral cat population, which has driven the decline of bird, mammal, and reptile species. Population control includes spaying and neutering.

Bears are carnivoran mammals of the family Ursidae (/ˈɜːrsɪdiː, -daɪ/). They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout most of the Northern Hemisphere and partially in the Southern Hemisphere. Bears are found on the continents of North America, South America, and Eurasia. Common characteristics of modern bears include large bodies with stocky legs, long snouts, small rounded ears, shaggy hair, plantigrade paws with five nonretractile claws, and short tails.

While the polar bear is mostly carnivorous, and the giant panda is mostly herbivorous, the remaining six species are omnivorous with varying diets. With the exception of courting individuals and mothers with their young, bears are typically solitary animals. They may be diurnal or nocturnal and have an excellent sense of smell. Despite their heavy build and awkward gait, they are adept runners, climbers, and swimmers. Bears use shelters, such as caves and logs, as their dens; most species occupy their dens during the winter for a long period of hibernation, up to 100 days.