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User:Carruxton/Snake skin

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Article Draft Plan of Action[edit]

1) Tackle the "Lead," give a better definition of snake skin and '"deplagiarize" the lead.

2) Moving and adding information to "Protection and Friction Reduction."

3) Combining the "Iridesence" section in with the "Color" section.

4) Add to "Movement and Flexibility".

Rough Draft[edit]

Lead:

Snakeskin can refer to the skin of a live snake, the shed skin of a snake after molting, or to a type of leather that is made from the hide of a dead snake. When a snake is alive, its skin often deals with various forms of abrasion. To combat rough substrates snakes have formed specialized and multilayered organizational epidermal structures to provide a safe and efficient sliding locomotion when maneuvering over rough surfaces.[1]

Protection and Friction Reduction:

The skin of a snake is a physically protective layer. It helps prevent injury, prevents drying out, and helps snakes to minimize friction. Because snakes lack limbs, their bodies are in contact with some surface at all times, which produces a huge amount of friction. As a result, they have to both minimize friction in order to move forward, and generate their own friction in order to generate enough propulsion to move. Scale and skin orientation helps to accomplish this, and it has been demonstrated that nanostructures on their scales may play a role in this process. The protection provided by scales and skin are in the form of keratin. Snakeskin is composed of a soft, flexible inner layer (alpha-layer), as well as a hard, inflexible outer surface (beta-layer).[1][2] The alpha-layer contains alpha-keratins that serve as cytoskeletal proteins as a mechanical form of resistance against traction. In relation, beta-keratins aid in formation of scales, as the keratin proteins produce a pre-corneous layer of densely packed epidermal scales creating a thick corneous protective layer.[2] To reduce friction, some snakes polish their scales. They secrete an oily substance from their nasal passage, and then rub the secretion all over the scales. This is done at varying intervals depending on the species of snake, sometimes frequently, other times only after shedding or molting. It is thought that scale polishing is used as a method of waterproofing, and it may also play a role in chemical messaging or friction reduction."

Color and Iridesence:

Coloration of snakes is largely due to pigment cells and their distribution. Some scales have lightly colored centers, which arise from regions with a reduced cuticle. A thinner cuticle indicates that some sensory organ is present. Scales in general are numerous and coat the epidermis, and they come in all shapes and colors. They are helpful in identification of snake species. Chromatophores in the dermis yield coloration when light shines through the corneal layer of the epidermis. There are many kinds of chromatophores. Melanophores yield brown pigmentation, and when paired with guanophores, yield grey. When paired with guanophores and lipophores, yellow results, and when guanophores and allophores are added to melanophores, red pigment results. Carotenoids also help produce orange and red colors. Dark snakes (dark brown or black in color) appear as such due to melanocytes that are active in the epidermis. When melanin is absent, albino individuals result. Snakes do not possess blue or green pigments, instead these arise from guanophores, which are also called Iridocytes. Iridocytes reside in the dermis and are responsible for the iridescent appearance of many dark-colored snakes. Males and females may show varied coloration, as might hatchlings and adults of the same species.

Movement and Flexibility:

"The skin that lies beneath snake's scales is also responsible for snakes' flexibility. The regions between snake scales is made of soft integument called an alpha-layer, which is composed of alpha-keratin that allows for flexibility and movement.[1][2] Snake mobility is dependent on the skin's contact to a friction surface, the tribological behavior of the snake skin allows for a quick and precise change in direction. For smooth gliding to occur, snakeskin is composed of sharp spines and interlocking logitudinal ridges. The snakeskin is also comprised of highly organized 'micro-hairs' along the ventral surface, oriented in a caudal direction. With both of these features, the snake is able to efficiently slide forward on surfaces of low friction, and create high friction when needs to retreat backwardly.[3]

- Thought Process Behind the Revisions -[edit]

The Lead[edit]

1) Plan: Start off by giving snakeskin a definition that includes a citation, as this version (below) does not have a citation, and could be elaborated on.

Current version:

"Snakeskin may either refer to the skin of a live snake, the shed skin of a snake after molting, or to a type of leather that is made from the hide of a dead snake"

Taken from the text:

"Snakes are limbless reptiles that use their entire body for sliding locomotion....Because the epidermis is constantly in contact with the solid substrates, one can expect some specializations in the snake epidermis against abrasion. Such specializations include layered organization of the epidermis, material properties of the epidermis and its surface microstructure"[1]

My version -

Snakeskin can refer to the skin of a live snake, the shed skin of a snake after molting, or to a type of leather that is made from the hide of a dead snake. When a snake is alive, its skin often deals with various forms of abrasion. To combat rough substrates snakes have formed specialized and multilayered organizational epidermal structures to provide a safe and efficient sliding locomotion when maneuvering over rough surfaces.[1]

Protection and Friction Reduction[edit]

2) Plan: I would like to move this under "Structures and Function" as I feel that they would be more closely related, since a big function is protection in organisms. I would also like to include more about keratinization in this area, since that is a big aspect of protection.

Current version

"The skin of a snake is a physically protective layer. It helps prevent injury, prevents drying out, and helps snakes to minimize friction. Because snakes lack limbs, their bodies are in contact with some surface at all times, which produces a huge amount of friction. As a result, they have to both minimize friction in order to move forward, and generate their own friction in order to generate enough propulsion to move. Scale and skin orientation helps to accomplish this, and it has been demonstrated that nanostructures on their scales may play a role in this process. Some snakes polish their scales. They secrete an oily substance from their nasal passage, and then rub the secretion all over the scales. This is done at varying intervals depending on the species of snake, sometimes frequently, other times only after shedding or molting. It is thought that scale polishing is used as a method of waterproofing, and it may also play a role in chemical messaging or friction reduction."

Taken From text:

"of snakes consists of a hard, robust, inflexible outer surface (Oberha¨utchen and b-layer) and soft, flexible inner layers (a-layers)".[1]

"The epidermis of reptiles produces two classes of keratins, soft or alpha-keratins and hard or beta-keratins...renewal phase, the epidermis in both snake species comprised an external (hard) outer beta-layer, followed by an outer alpha-layer and a forming (inner) beta-layer made of fusiform cells...Cytokeratins (alpha-keratins) are present in most epidermal layers where they serve as cytoskeletal proteins for the mechanical resistance to traction, impart the form to cells, or determine their changes in shape....Beta-keratins are small and specific proteins forming hard appendages in sauropsids (scales, scutes, claws, beak, feathers, etc.). These proteins are produced in the precorneous layer of the epidermis of scales (Sawyer et al., 2000). The small dimension, and the variable amount of disulphuric and other chemical bonds present in beta-keratins allow a dense packaging to build thick and hard corneous material. This combination of alpha- and beta-keratins or the prevalence of beta-keratin in beta-cells determines the formation of a dense and hard corneous material in reptilian scales"[2]

My Version:

The skin of a snake is a physically protective layer. It helps prevent injury, prevents drying out, and helps snakes to minimize friction. Because snakes lack limbs, their bodies are in contact with some surface at all times, which produces a huge amount of friction. As a result, they have to both minimize friction in order to move forward, and generate their own friction in order to generate enough propulsion to move. Scale and skin orientation helps to accomplish this, and it has been demonstrated that nanostructures on their scales may play a role in this process. The protection provided by scales and skin are in the form of keratin. Snakeskin is composed of a soft, flexible inner layer (alpha-layer), as well as a hard, inflexible outer surface (beta-layer).[1][2] The alpha-layer contains alpha-keratins that serve as cytoskeletal proteins as a mechanical form of resistance against traction. In relation, beta-keratins aid in formation of scales, as the keratin proteins produce a pre-corneous layer of densely packed epidermal scales creating a thick corneous protective layer.[2] To reduce friction, some snakes polish their scales. They secrete an oily substance from their nasal passage, and then rub the secretion all over the scales. This is done at varying intervals depending on the species of snake, sometimes frequently, other times only after shedding or molting. It is thought that scale polishing is used as a method of waterproofing, and it may also play a role in chemical messaging or friction reduction."

Color[edit]

3) Plan: Combine Color and Iridesence.

Current version:

Coloration of snakes is largely due to pigment cells and their distribution. Some scales have lightly colored centers, which arise from regions with a reduced cuticle. A thinner cuticle indicates that some sensory organ is present. Scales in general are numerous and coat the epidermis, and they come in all shapes and colors. They are helpful in identification of snake species. Chromatophores in the dermis yield coloration when light shines through the corneal layer of the epidermis. There are many kinds of chromatophores. Melanophores yield brown pigmentation, and when paired with guanophores, yield grey. When paired with guanophores and lipophores, yellow results, and when guanophores and allophores are added to melanophores, red pigment results. Carotenoids also help produce orange and red colors. Dark snakes (dark brown or black in color) appear as such due to melanocytes that are active in the epidermis. When melanin is absent, albino individuals result. Snakes do not possess blue or green pigments. These arise from guanophores, which are also called iridocytes. These reside in the dermis.

My version: "Color and Iridesence"

-The added changes are in bold- just merging "Iridesence" with "Color"

Coloration of snakes is largely due to pigment cells and their distribution. Some scales have lightly colored centers, which arise from regions with a reduced cuticle. A thinner cuticle indicates that some sensory organ is present. Scales in general are numerous and coat the epidermis, and they come in all shapes and colors. They are helpful in identification of snake species. Chromatophores in the dermis yield coloration when light shines through the corneal layer of the epidermis. There are many kinds of chromatophores. Melanophores yield brown pigmentation, and when paired with guanophores, yield grey. When paired with guanophores and lipophores, yellow results, and when guanophores and allophores are added to melanophores, red pigment results. Carotenoids also help produce orange and red colors. Dark snakes (dark brown or black in color) appear as such due to melanocytes that are active in the epidermis. When melanin is absent, albino individuals result. Snakes do not possess blue or green pigments, instead these arise from guanophores, which are also called Iridocytes. Iridocytes reside in the dermis and are responsible for the iridescent appearance of many dark-colored snakes. Males and females may show varied coloration, as might hatchlings and adults of the same species.

Movement and Flexibility[edit]

I think this could be its own area. There are only two sentences on this, but I would like to try to find more information on this.

Current version:

"The skin that lies beneath snake's scales is also responsible for snakes' flexibility. The regions between snake scales is made of soft integument that allows for movement".

Taken From Text:

"A key element of this event is tribological (frictional) behavior of snake skin, which allows precise change of local direction and pace of sliding. Studies of macroscopic frictional properties of snake bodies showed a friction coefficient in the range from 0.2 to 0.4 for the forward motion on various dry surfaces (Gray and Lissmann, 1950). However, a substantial increase in the friction forces was observed on oiled surfa�ces....such as sharp spines designed to protect snake skins and interlocking longitudinal ridges to allow smooth sliding. The presence of a complex lipid film on a surface to control dermal wettability and permeability was indicated by several studies...The first striking feature of all skin areas along the snake ventral surface involved in locomotion is the pres�ence of highly organized arrays of ‘micro-hairs’ (Fig. 1)...In both cases, the microfibrils are oriented in the direction of motion with their ends having caudal orientation (toward the tail of the animal). All microfibrils possess uniform lateral sizes with diameter.....arrays are separated by sharp grooves running along the snake backbone and making strips 10—20 lm....icrofibrils above their ‘ground’ level. This design pro�vides significant frictional anisotropy: low friction for forward sliding motion and high friction for backward motion....[3]

My version:

"The skin that lies beneath snake's scales is also responsible for snakes' flexibility. The regions between snake scales is made of soft integument called an alpha-layer, which is composed of alpha-keratin that allows for flexibility and movement.[1][2] Snake mobility is dependent on the skin's contact to a friction surface, the tribological behavior of the snake skin allows for a quick and precise change in direction. For smooth gliding to occur, snakeskin is composed of sharp spines and interlocking logitudinal ridges. The snakeskin is also comprised of highly organized 'micro-hairs' along the ventral surface, oriented in a caudal direction. With both of these features, the snake is able to efficiently slide forward on surfaces of low friction, and create high friction when needs to retreat backwardly.[3]

Peer Review Summary Section 4/8/22[edit]

Based on the peer reviews that I recieved:

- Will continue finding new/more sources that could be helpful to the page. It was also suggested that I use the textbook and other anatomy textbooks as well.

- Since my main focus is the "Snakeskin" page, to possibly relate it back to "Snake Anatomy," I could embedd a link there somewhere. However, still all my edits will be done on the "Snakeskin" page.

- In my sandbox, embedd the wikipedia page I am working on.

- Add images.

- Add some embedded/hyperlinked components to certain words or phrases to help readers better navigate through the text.

Final Draft 4/29/22[edit]

- Adding what is in bold to the active wikipedia page - Little by little...Anything crossed out has been added to the Live Snakeskin Page.

  • First plan of action is to ask the Snakeskin Talk page about an addition to the "Lead" and combining the "Color" and "Irridesence" paragraphs together.

1) Tackle the "Lead," possibly add a "Summary" as well.

Proposed summary -

Snakeskin may either refer to the skin of a living snake, the shed skin of a snake after molting, or to a type of leather that is made from the hide of a dead snake. Snakeskin and scales can have varying patterns and color formations, to provide protection via camouflage from predators [3 Mattison Chris, Encycolpeida of snakes]. The colors and iridescene in these scales are largely determined by the types and amount of chromatophores located in the dermis of the snake skin [4 Bauchot Roland]. The snake's skin and scales are also an important feature to their locomotion, providing protection and minimizing friction when gliding over surfaces [Parker7,Toni8,Filippov9,Yang11].

The Lead for 'Skin of a Living Snake'

In a living snake, its skin often deals with various forms of abrasion. To combat rough substrates snakes have formed specialized and multilayered organizational epidermal structures to provide a safe and efficient sliding locomotion when maneuvering over rough surfaces.[1]

2) Moving and adding information to "Protection and Friction Reduction."

The skin of a snake is a physically protective layer. It helps prevent injury, prevents drying out, and helps snakes to minimize friction. Because snakes lack limbs, their bodies are in contact with some surface at all times, which produces a huge amount of friction. As a result, they have to both minimize friction in order to move forward, and generate their own friction in order to generate enough propulsion to move. Scale and skin orientation helps to accomplish this, and it has been demonstrated that nanostructures on their scales may play a role in this process. The protection provided by scales and skin are in the form of keratin. Snakeskin is composed of a soft, flexible inner layer (alpha-layer), as well as a hard, inflexible outer surface (beta-layer).[1][2] The alpha-layer contains alpha-keratins that serve as cytoskeletal proteins as a mechanical form of resistance against traction. In relation, beta-keratins aid in formation of scales, as the keratin proteins produce a pre-corneous layer of densely packed epidermal scales creating a thick corneous protective layer.[2] To reduce friction, some snakes polish their scales. They secrete an oily substance from their nasal passage, and then rub the secretion all over the scales. This is done at varying intervals depending on the species of snake, sometimes frequently, other times only after shedding or molting. It is thought that scale polishing is used as a method of waterproofing, and it may also play a role in chemical messaging or friction reduction."

3) Combining the "Iridesence" section in with the "Color" section, along with the addition of a picture/photo.

The variation of scale colors as caused by different chromatophores, located on the dorsal surface of a Garter snake.

Coloration of snakes is largely due to pigment cells and their distribution. Some scales have lightly colored centers, which arise from regions with a reduced cuticle. A thinner cuticle indicates that some sensory organ is present. Scales in general are numerous and coat the epidermis, and they come in all shapes and colors. They are helpful in identification of snake species. Chromatophores in the dermis yield coloration when light shines through the corneal layer of the epidermis. There are many kinds of chromatophores. Melanophores yield brown pigmentation, and when paired with guanophores, yield grey. When paired with guanophores and lipophores, yellow results, and when guanophores and allophores are added to melanophores, red pigment results. Carotenoids also help produce orange and red colors. Dark snakes (dark brown or black in color) appear as such due to melanocytes that are active in the epidermis. When melanin is absent, albino individuals result. Snakes do not possess blue or green pigments, instead these arise from guanophores, which are also called Iridocytes. Iridocytes reside in the dermis and are responsible for the iridescent appearance of many dark-colored snakes. Males and females may show varied coloration, as might hatchlings and adults of the same species.

4) Add to "Movement and Flexibility".

"The skin that lies beneath snake's scales is also responsible for snakes' flexibility. The regions between snake scales is made of soft integument called an alpha-layer, which is composed of alpha-keratin that allows for flexibility and movement.[1][2] Snake mobility is dependent on the skin's contact to a friction surface, the tribological behavior of the snake skin allows for a quick and precise change in direction. For smooth gliding to occur, snakeskin is composed of sharp spines and interlocking logitudinal ridges. The snakeskin is also comprised of highly organized 'micro-hairs' along the ventral surface, oriented in a caudal direction. With both of these features, the snake is able to efficiently slide forward on surfaces of low friction, and create high friction when needs to retreat backwardly.[4]

Additional changes I made to the Snakeskin page:

5) Combined 'Molting' to 'Shed Skin' area.

6) Embedded links to words people may not know.

References[edit]

  1. ^ a b c d e f g h i j k Klein, Marie-Christin G.; Gorb, Stanislav N. (2012-11-07). "Epidermis architecture and material properties of the skin of four snake species". Journal of The Royal Society Interface. 9 (76): 3140–3155. doi:10.1098/rsif.2012.0479. ISSN 1742-5689. PMC 3479930. PMID 22896567.{{cite journal}}: CS1 maint: PMC format (link)
  2. ^ a b c d e f g h i j Toni, Mattia; Alibardi, Lorenzo (2007-02-01). "Alpha- and beta-keratins of the snake epidermis". Zoology. 110 (1): 41–47. doi:10.1016/j.zool.2006.07.001. ISSN 0944-2006.
  3. ^ a b c Yang, Zhu II, Li III, Sun IV, Chen V, Yan VI, Liu VII, Chen VII, Zhe, Liangliang. "Elsevier Enhanced Reader". reader.elsevier.com. Retrieved 2022-03-21.{{cite web}}: CS1 maint: multiple names: authors list (link)
  4. ^ Yang, Zhe; Zhu, Liangliang; Li, Botong; Sun, Shuocheng; Chen, Youlong; Yan, Yuan; Liu, Yilun; Chen, Xi (2016-09-01). "Mechanical design and analysis of a crawling locomotion enabled by a laminated beam". Extreme Mechanics Letters. Nanomechanics: Bridging Spatial and Temporal Scales. 8: 88–95. doi:10.1016/j.eml.2016.03.014. ISSN 2352-4316.

Ignore Citation #3 above - it won't let me delete it-