A hindlimb or back limb is one of the paired

articulated An articulated vehicle is a vehicle which has a permanent or semi-permanent pivot joint in its construction, allowing it to turn more sharply. There are many kinds, from heavy equipment to buses, trams and trains. Steam locomotives were someti ...

appendage An appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's body. In arthropods, an appendage refers to any of the homologous body parts that may extend from a body segment, including anten ...

s (

limb Limb may refer to: Science and technology *Limb (anatomy), an appendage of a human or animal *Limb, a large or main branch of a tree *Limb, in astronomy, the curved edge of the apparent disk of a celestial body, e.g. lunar limb *Limb, in botany, ...

s) attached on the caudal ( posterior) end of a

terrestrial Terrestrial refers to things related to land or the planet Earth. Terrestrial may also refer to: * Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...

tetrapod Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids (pelycosaurs, extinct theraps ...

vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...

torso The torso or trunk is an anatomical term for the central part, or the core, of the body of many animals (including humans), from which the head, neck, limbs, tail and other appendages extend. The tetrapod torso — including that of a human � ...

.http://www.merriam-webster.com/medical/hind%20limb, Merriam Webster Dictionary-Hindlimb With reference to

quadruped Quadrupedalism is a form of locomotion where four limbs are used to bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four limbs is said to be a quadruped (from Latin ''quattuor' ...

s, the term hindleg or back leg is often used instead. In

bipedal Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' ...

animals with an

upright Body relative directions (also known as egocentric coordinates) are geometrical orientations relative to a body such as a human person's. The most common ones are: left and right; forward(s) and backward(s); up and down. They form three pairs ...

posture (e.g.

humans Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

and some

primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians (monkeys and apes, the latter including huma ...

s), the term

lower limb The human leg, in the general word sense, is the entire lower limb of the human body, including the foot, thigh or sometimes even the hip or gluteal region. However, the definition in human anatomy refers only to the section of the lower limb ext ...

is often used.

Location

It is located on the limb of an animal. Hindlimbs are present in a large number of quadrupeds. Though it is a posterior limb, it can cause lameness in some animals. The way of walking through hindlimbs are called

bipedalism Bipedalism is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' a ...

Benefits of hindlimbs

Hindlimbs are helpful in many ways, some examples are:

Frogs

Frogs can easily adapt at the surroundings using hindlimbs. The main reason is it can

jump Jumping is a form of locomotion or movement in which an organism or non-living (e.g., robotic) mechanical system propels itself through the air along a ballistic trajectory. Jump or Jumping also may refer to: Places * Jump, Kentucky or Jump S ...

high to easily escape to its predator and also to catch prey. It can perform some tricks using the hindlimbs such as the somersault and hindersault. Frogs have 4 digits in fore limb while hindlimb have 5 digits. All digits are without nails.

Birds

All birds walk using hindlimbs. They have the ability to dig in two opposite directions using the hindlimbs. They can easily find food that makes them adapt on their surroundings. A bird with a forelimb that is very primitive is the

Archaeopteryx ''Archaeopteryx'' (; ), sometimes referred to by its German name, "" ( ''Primeval Bird''), is a genus of bird-like dinosaurs. The name derives from the ancient Greek (''archaīos''), meaning "ancient", and (''ptéryx''), meaning "feather" ...

. It adapted by using it but it was not capable of long-distance flights, leading to its extinction. The fastest biped is the ostrich. It runs at 70 km/h.

Kangaroo rats

Bipedality in kangaroo rats are seen to be an agent of adaptation. Kangaroo rats are long jumpers that can jump up to 18 feet, (that is twice the highest possible long jump and also high jump). Using hindlimbs they can survive a challenging ecosystem. They can easily find food and survive hindrances in the environment. Some species use hindlimbs for competition.

First bipeds

The first vertebrate bipeds were the Bolosaurids, a group of prehistoric reptiles with no living relatives. The first one,

Eudibamus ''Eudibamus'' is an extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, alth ...

, was a small, fast runner during the

Permian Period The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozo ...

References

{{Reflist Animal anatomy Lower limb anatomy