Edits for Facultative Biped page:

INTRO: add links in facultative and biped in the first sentence, see below. Also, see grammar/fluency edits below. Otherwise, it appropriately covers the topic and provides information. You may want to include information linking it the evolution of bipedalism section.

A facultative biped is a animal that is capable of walking or running on two legs, often for only a limited period, in spite of normally walking or running on four limbs or more.[1] It differs from obligate bipedalism in that facultative bipeds use four limbs as their primary method of locomotion, only occasionally becoming bipedal, often for a specific purpose. Facultative bipedalism has been observed in several families of lizards and multiple species of primates, including sifakas, capuchin monkeys, baboons, gibbons, and chimpanzees. There are different types of bipedal motion, which correspond to the different reasons various species have for engaging in facultative bipedalism. In primates, bipedalism is often associated with food gathering and transport.[2] The exact reason for bipedal locomotion in lizards is debated, with one argument that it is an advantage for speed and energy conservation and another it is governed solely by the mechanics of the acceleration and lizard's center of mass.[3] Facultative bipedalism is often divided into high-speed (lizards)[4] and low-speed (gibbons),[5] with some species failing to be easily categorized. Facultative bipedalism has also been observed in cockroaches[6] and some desert rodents.[7]

TYPES OF BIPEDAL LOCOMOTION: Great section, short and to the point. Changed one word. You may want to include some more information on what the other forms of bipedalism are, and why they are not frequently utilized. Also, whether certain forms of bipedalism are more common in facultative bipeds or in obligate bipeds.

Within the category of bipedal locomotion, there are a four main techniques: walking, running, skipping, and galloping.[8]Walking is when the footfalls have an evenly spaced gait, and one foot is always on the ground.[8] When both feet are off the ground at the same time, called the aerial phase, this is running.[8] Skipping is when there is an aerial phase, but the two feet hit the ground immediately after each other, and the trailing foot changes after each step.[8] Galloping is similar to skipping, but the trail foot does not change after each step.[8] While not an exhaustive list of the forms of bipedalism, but most bipedal species utilize one or more of these techniques.[8]

FACULTATIVE BIPED SPECIES: Some grammar and structure edits.

"specific lizard families known as facultative bipeds are the Agamidae, Crotaphytidae, Iguanidae, and Phrynosomatidae.[9][10]" This part of the intro can be moved down to the lizard section.

"The Sifaka, Propithecus, a type of lemur native to the island of Madagascar," edited. "is one of the primary examples of facultative bipedalism." this sounds like an opinion, cite your source or remove it.

"Sifakas can locomote bipedally in two separate ways: walking and galloping.[11]" grammatical error.

Types of Bipedal Locomotion

edit

This is a very basic and simple overview that is currently lacking from the page. Having this will increase the clarity of the definition and provide context for the reader.

●      Walking – evenly spaced gait[12]

●      Running – has a period where both feet are off the ground[12]

●      Skipping  - both feet are off the ground and then hit the ground right after each other, trailing foot changes each step[12]

●      Galloping – similar to skipping, but the trailing foot stays the same in each step[12]

Within the category of bipedal locomotion, there are a four main techniques: walking, running, skipping, and galloping.[12] Walking is when the footfalls have an evenly spaced gait, and one foot is always on the ground.[12] When both feet are off the ground at the same time, called the aerial phase, this is running.[12] Skipping is when there is an aerial phase, but the two feet hit the ground immediately after each other, and the trailing foot changes after each step. [12] Galloping is similar to skipping, but the trail foot does not change after each step.[12] This is not an exhaustive list of the forms of bipedalism, but most bipedal species utilize one or more of these techniques.[12]

  1. ^ Persons, W. Scott; Currie, Philip J. (2017). "The functional origin of dinosaur bipedalism: Cumulative evidence from bipedally inclined reptiles and disinclined mammals". Journal of Theoretical Biology. 420: 1–7. doi:10.1016/j.jtbi.2017.02.032. PMID 28254476.
  2. ^ Hunt, Kevin D. (1996-02-01). "The postural feeding hypothesis: an ecological model for the evolution of bipedalism". South African Journal of Science. 92 (2): 77–90. hdl:10520/AJA00382353_7777.
  3. ^ Clemente, C. J.; Withers, P. C.; Thompson, G.; Lloyd, D. (2008). "Why go bipedal? Locomotion and morphology in Australian agamid lizards". Journal of Experimental Biology. 211 (13): 2058–2065. doi:10.1242/jeb.018044. PMID 18552294.
  4. ^ Schuett, Gordon W.; Reiserer, Randall S.; Earley, Ryan L. (2009). "The evolution of bipedal postures in varanoid lizards". Biological Journal of the Linnean Society. 97 (3): 652–663. doi:10.1111/j.1095-8312.2009.01227.x.
  5. ^ Preuschoft, Holger (2004). "Mechanisms for the acquisition of habitual bipedality: Are there biomechanical reasons for the acquisition of upright bipedal posture?". Journal of Anatomy. 204 (5): 363–384. doi:10.1111/j.0021-8782.2004.00303.x. PMC 1571303. PMID 15198701.
  6. ^ Alexander, R. McN. (2004). "Bipedal animals, and their differences from humans". Journal of Anatomy. 204 (5): 321–330. doi:10.1111/j.0021-8782.2004.00289.x. PMC 1571302. PMID 15198697.
  7. ^ Russo, Gabrielle A.; Kirk, E. Christopher (2013). "Foramen magnum position in bipedal mammals". Journal of Human Evolution. 65 (5): 656–670. CiteSeerX 10.1.1.591.2458. doi:10.1016/j.jhevol.2013.07.007. PMID 24055116.
  8. ^ a b c d e f Wunderlich, R. E.; Schaum, J. C. (2007). "Kinematics of bipedalism in Propithecus verreauxi". Journal of Zoology. 272 (2): 165–175. doi:10.1111/j.1469-7998.2006.00253.x.
  9. ^ Schuett, Gordon W.; Reiserer, Randall S.; Earley, Ryan L. (2009). "The evolution of bipedal postures in varanoid lizards". Biological Journal of the Linnean Society. 97 (3): 652–663. doi:10.1111/j.1095-8312.2009.01227.x.
  10. ^ Alexander, R. McN. (2004). "Bipedal animals, and their differences from humans". Journal of Anatomy. 204 (5): 321–330. doi:10.1111/j.0021-8782.2004.00289.x. PMC 1571302. PMID 15198697.
  11. ^ Wunderlich, R. E.; Schaum, J. C. (2007). "Kinematics of bipedalism in Propithecus verreauxi". Journal of Zoology. 272 (2): 165–175. doi:10.1111/j.1469-7998.2006.00253.x.
  12. ^ a b c d e f g h i j Wunderlich, R. E.; Schaum, J. C. (2007). "Kinematics of bipedalism in Propithecus verreauxi". Journal of Zoology. 272 (2): 165–175. doi:10.1111/j.1469-7998.2006.00253.x. ISSN 0952-8369.