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Which animals perspire?

  1. Jan 23, 2004 #1
    Besides humans, which animals perspire?

    Dogs don't perspire, right? Do cats perspire?
  2. jcsd
  3. Jan 23, 2004 #2
    I was under the assumption that all mammals have sweat glands. They all produce milk, which are modified sweat glands.

  4. Jan 23, 2004 #3

    All mammals share three characteristics not found in other animals: 3 middle ear bones; hair; and the production of milk by modified sweat glands called mammary glands.

    Mammals hear sounds after they are transmitted from the outside world to their inner ears by a chain of three bones, the malleus, incus, and stapes. Two of these, the malleus and incus, are derived from bones involved in jaw articulation in most other vertebrates.

    Mammals have hair. Adults of some species lose most of their hair, but hair is present at least during some phase of the ontogeny of all species. Mammalian hair, made of a protein called keratin, serves at least four functions. First, it slows the exchange of heat with the environment (insulation). Second, specialized hairs (whiskers or "vibrissae") have a sensory function, letting the owner know when it is in contact with an object in its external environment. These hairs are often richly innervated and well-supplied with muscles that control their position. Third, through their color and pattern, hairs affect the appearance of a mammal. They may serve to camouflage, to announce the presence of especially good defense systems (for example, the conspicuous color pattern of a skunk is a warning to predators), or to communicate social information (for example, threats, such as the erect hair on the back of a wolf; sex, such as the different colors of male and female capuchin monkeys; presence of danger, such as the white underside of the tail of a whitetailed deer). Fourth, hair provides some protection, either simply by providing an additional protective layer (against abrasion or sunburn, for example) or by taking on the form of dangerous spines that deter predators (porcupines, spiny rats, others).

    Mammals feed their newborn young with milk, a substance rich in fats and protein that is produced by modified sweat glands called mammary glands. These glands, which take a variety of shapes, are usually located on the ventral surface of females along paths that run from the chest region to the groin. They vary in number from two (one right, one left, as in humans) to a dozen or more.

    Other characteristics found in most mammals include highly differentiated teeth; teeth are replaced just once during an individual's life (this condition is called diphyodonty, and the first set is called "milk teeth); a lower jaw made up of a single bone, the dentary; four-chambered hearts, a secondary palate separating air and food passages in the mouth; a muscular diaphragm separating thoracic and abdominal cavities; highly developed brain; endothermy and homeothermy; separate sexes with the sex of an embryo being determined by the presence of a Y or 2 X chromosomes; and internal fertilization.

    The Class Mammalia includes around 5000 species placed in 26 orders (systematists do not yet agree on the exact number or on how some orders are related to others). Mammals can be found in all continents and seas. In part because of their high metabolic rates (associated with homeothermy and endothermy), they often play an ecological role that seems disproportionately large compared to their numerical abundance.

    This site contains a number of resources for learning about mammals. Brief accounts describing the orders and families can be located by clicking on the appropriate order, listed below. Within each family account is a list of species for which materials are available in the Animal Diversity Web. A superscript "t" by the species name indicates that a description of the animal's natural history, conservation status, distribution, and classification (a "species account") is available. An "p" indicates the presence of a picture of the living animal; due to copyright restrictions, however, some of these pictures can only be seen at the University of Michigan. An "s" indicates closeup pictures of skulls, teeth, or other anatomical elements. Sets of these "anatomical" pictures are available for at least one species representing almost every family of mammal except cetaceans, and in many cases, multiple species. For each group, we've tried to illustrate some of the characteristics used to define the group or those that are important in understanding the diversity of its species. These materials are all available by clicking on the species name.

    In the descriptions of orders and families of mammals, we include some of the technical characteristics of skulls and dentition that are used to define and differentiate these groups. To make these easier to comprehend, we provide links to dorsal, ventral, and lateral views of the skull of a dog on which the major bones, foramina, and processes have been labelled. Closeups of the basicranial region, orbital region, and inside and outside of a mandible are also available. A partially labelled full skeleton of a raccoon has also been prepared.

    Additionally, special sections (listed in a "Special Topics Contents ") explore important aspects of mammals. At present, most of these deal with descriptive and functional anatomy. Most are abundantly illustrated with images of actual specimens. New sections are being added frequently, a process that will continue as we continue to develop this site.
  5. Jan 23, 2004 #4
    (Redirected from Sweat)

    Perspiration (or sweat) is a watery fluid, consisting mainly of sodium chloride and urea in solution, that is secreted by the sweat glands in the skin of mammals.

    In humans, sweating is a means of excreting nitrogenous waste products, but it is also, and more importantly, a means of temperature regulation. Evaporation of sweat from the skin surface has a cooling effect. Hence, in hot weather, or when the individual feels hot through exercise, more sweat is produced. Sweating is increased by nervousness and nausea and decreased by colds. Animals with few sweat glands, such as dogs, accomplish similar results by panting, evaporating water from the moist lining of the oral cavity and pharynx.

    Sweat glands
    Sweat glands are coiled tubular glands derived from the outer layer of skin but extending into the inner layer. They are distributed over almost the entire surface of the body in humans and many other species, but are lacking in some marine and fur-bearing species.

    The secretion of sweat glands varies greatly. In humans, sweat is composed chiefly of water with various salts and organic compounds in solution. It contains minute amounts of fatty materials, urea, and other wastes. The sweat of other species normally differ in composition.

    In some areas of the body the sweat glands are modified to produce wholly different secretions, however, including the wax of the outer ear. Some sweat glands, called apocrine glands, are modified into scent glands. Others are greatly enlarged and modified to produce milk. The ones used for temperature regulation are called eccrine glands.
  6. Jan 23, 2004 #5


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    One animal that do not sweat is the pig. Pig do not have sweet glands.

    So sweatingas a pig is incorrect.
  7. Jan 23, 2004 #6
    They have mammary glands which are modified sweat glands. It, also, has sweat glands on its nose.

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