Forelimbs Lab Report

Jason Ramdat, Lab Essay #2, Lab Code 1B, 12/8/14 Vertebrates’ forelimbs are anterior appendages of animals that are in the subphylum vertebrata. There are several bones that makes up a forelimb includes the radius, ulna, humerus, carpal, metacarpals, and phalanges. The humerus is a single heavy bone which articulates with the body and forms the foundation of the limb; the radius and ulna are lighter and provides support in addition to a greater range of movement (AMNH Plaque). The carpals, metacarpals, and phalanges are farthest away from the body and consist of many smaller bones giving a great deal of flexibility for movement and food acquisition (AMNH Plaque). How the limbs evolved illustrates its considerable plasticity for adaption for …show more content…
Chiroptera forelimb morphological evolution is what allows them the gift of flight, which is their forelimb main function. Their wings contain an altered tetrapod limb structure (Cooper and Tabin 2008). Changes include increasing membrane surface area between the digits and between the forelimb and flank (Cooper and Tabin 2008). In addition to a reduced bone thickness which decreases the bats weight (Cooper and Tabin 2008). Also a strengthen forelimb and increase in muscle mass of the forelimb, with and lengthen of forelimbs give allows them to attain flight (Cooper and Tabin 2008). Its humerus is closest to the body, thin and long in comparison to other mammals (Meyers et al 2014). Their radius is attached to the humerus and it is a long and thin nonetheless also a strong bone that supports the wing, while the ulna is reduced and fused with radius (Meyers et al 2014). Chiroptera wrists have been modified to support motions that deals with flying but has reduced flexible compared to other mammals (Meyers et al 2014). The bait forelimbs may be also used for climbing, defense, and for eating. This is allowed by their thumb that is located at the edge of the wing, containing a claw (Meyers et al 2014). Their wings membrane is an extension of their skin of their body which contains hairs (Meyers et al …show more content…
Human’s forelimbs are highly developed server main purposes and one of its main purposes is for grasping. The ability to grasp object with forelimbs is known as prehensile movement (Estrella Mountain). Another modification is the opposable thumb, which allows the touch our finger with the thumb (Estrella Mountain). In addition to grasping humans forelimb can be used for carrying, holding, using objects, and defense (Saladin 2003). Human’s forelimbs are shortened and are decreased in strength compared to apes (Ruff 2003). That is due to being bipedal, having short forelimbs and long hind limbs give humans the ability to walk upright (Saladin 2003). Having the ball and socket shoulder joint gives them the ability of 360 range of motion (PBS

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