A forelimb or front limb is one of the paired articulated appendages (limbs) attached on the cranial (anterior) end of a terrestrial tetrapod vertebrate's torso. With reference to quadrupeds, the term foreleg or front leg is often used instead. In bipedal animals with an upright posture (e.g. humans and some primates), the term upper limb is often used.
A forelimb is not to be confused with a forearm, which is a distal portion of the human upper limb between the elbow and the wrist.
All vertebrate forelimbs are homologous, meaning that they all evolved from the same structures. For example, the flipper of a turtle or of a dolphin, the arm of a human, the foreleg of a horse, and the wings of both bats and birds are ultimately homologous, despite the large differences between them.[1]
Specific uses of the forelimbs may be analogous if they evolved from different sub-structures of the forelimb, such as the flippers of turtles and dolphins, and the wings of birds and bats.[2]
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