Non human senses

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Analogous to human senses

Other living organisms have receptors to sense the world around them, including many of the senses listed above for humans. However, the mechanisms and capabilities vary widely.
[edit] Echolocation

Certain animals, including bats and cetaceans, have the ability to determine orientation to other objects through interpretation of reflected sound (like sonar). They most often use this to navigate through poor lighting conditions or to identify and track prey. There is currently an uncertainty whether this is simply an extremely developed post-sensory interpretation of auditory perceptions or it actually constitutes a separate sense. Resolution of the issue will require brain scans of animals while they actually perform echolocation, a task that has proven difficult in practice. Blind people report they are able to navigate by interpreting reflected sounds (esp. their own footsteps), a phenomenon which is known as human echolocation.
[edit] Smell

Among non-human species, dogs have a much keener sense of smell than humans, although the mechanism is similar. Insects have olfactory receptors on their antennae. Some animals have a vomeronasal organ which is mainly used to detect pheromones; the organ is vestigial in humans and separate from the main olfactory system, analogous to the human sense of smell.
[edit] Vision

Cats have the ability to see in low light due to muscles surrounding their irises to contract and expand pupils as well as the tapetum lucidum, a reflective membrane that optimizes the image. Pitvipers, pythons and some boas have organs that allow them to detect infrared light, such that these snakes are able to sense the body heat of their prey. The common vampire bat may also have an infrared sensor on its nose.[13] It has been found that birds and some other animals are tetrachromats and have the ability to see in the ultraviolet down to 300 nanometers. Bees and dragonflies[14] are also able to see in the ultraviolet.
[edit] Balance

Ctenophora have a balance receptor (a statocyst) that works very differently from the mammalian's semi-circular canals.
[edit] Not analogous to human senses

In addition, some animals have senses that humans do not, including the following:

* Electroception (or electroreception) is the ability to detect electric fields. Several species of fish, sharks and rays have the capacity to sense changes in electric fields in their immediate vicinity. Some fish passively sense changing nearby electric fields; some generate their own weak electric fields, and sense the pattern of field potentials over their body surface; and some use these electric field generating and sensing capacities for social communication. The mechanisms by which electroceptive fish construct a spatial representation from very small differences in field potentials involve comparisons of spike latencies from different parts of the fish's body.

The only order of mammals that is known to demonstrate electroception is the monotreme order. Among these mammals, the platypus[15] has the most acute sense of electroception.

Body modification enthusiasts have experimented with magnetic implants to attempt to replicate this sense,[16] however in general humans (and probably other mammals) can detect electric fields only indirectly by detecting the effect they have on hairs. An electrically charged balloon, for instance, will exert a force on human arm hairs, which can be felt through tactition and identified as coming from a static charge (and not from wind or the like). This is however not electroception as it is a post-sensory cognitive action.

* Pressure detection uses the organ of Weber, a system consisting of three appendages of vertebrae transferring changes in shape of the gas bladder to the middle ear. It can be used to regulate the buoyancy of the fish. Fish like the weather fish and other loaches are also known to respond to low pressure areas but they lack a swim bladder.

* Current detection The lateral line in fish and aquatic forms of amphibians is a detection system of water currents, mostly consisting of vortices. The lateral line is also sensitive to low frequency vibrations. The mechanoreceptors are hair cells, the same mechanoreceptors for vestibular sense and hearing. It is used primarily for navigation, hunting, and schooling. The receptors of the electrical sense are modified hair cells of the lateral line system.

* Polarized light direction/detection is used by bees to orient themselves, especially on cloudy days. Cuttlefish can also perceive the polarization of light. Most sighted humans can in fact learn to roughly detect large areas of polarization by an effect called Haidinger's brush, however this is considered an entoptic phenomenon rather than a separate sense.

* Slit sensillae of spiders detect mechanical strain in the exoskeleton, providing information on force and vibrations.