User:KoreanBobsledder/sandbox

Gameplan
Insert neoteny subsection in the 'appearance' portion of the Common mudpuppy page. Insert more information about external gills in the 'other vertebrates' section of the salamander page.

Mudpuppies are one of many species of salamanders that fall to undergo metamorphosis. Most hypotheses surrounding the origin of Necturus 's lack of metamorphosis concern the effectiveness of the thyroid gland. The thyroid gland in some salamanders, like the Axolotl, produce normal thyroid hormones (THs), but cells in the organism express thyroid hormone receptors (TR) that are mutated, and do not bond correctly with thyroid hormones, leading to some salamanders in a state of perpetual juvenile-hood. In mudpuppies, these THs are normally expressed unlike the Axolotl. However, it is believed that instead of having TH-insensitive tissues that block the effects of THs, some mudpuppy tissues, such as the external gills, have lost the ability to be regulated by TH over time. This selective insensitivity to THs suggests a normal level of activity in the hypothalamo-pituitary-thyroid axis in developing mudpuppies, unlike other salamander breeds.

The common mudpuppy also does not have a parathyroid gland. The majority of salamanders with parathyroid glands rely on them to help with hypercalcemic regulation; hypercalcemic regulation in mudpuppies is primarily done by the Pituitary gland instead. In common mudpuppies, the purpose of the absence of a parathyroid gland is poorly understood. One reason for the absence might be the lack of variability in the climate of mudpuppies, as the parathyroid glands of salamanders vary greatly depending on seasonal changes, or whether the organism hibernates.

In Necturus, external gills begin to form as a means of combating hypoxia in the egg as egg yolk is converted into metabolically active tissue. However, molecular changes in the mudpuppy during post-embryonic development primarily due to the thyroid gland prevent the internalization of the external gills as seen in most salamanders that undergo metamorphosis. The external gills seen in salamanders differs greatly from that of amphibians with internalized gills.Unlike amphibians with internalized gills which typically rely on the changing of pressures within the buccal and pharyngeal cavities to ensure diffusion of oxygen onto the gill curtain, neotenic salamanders such as Necturus use specified musculature to move external gills to keep the respiratory surfaces constantly in contact with new oxygenated water

Joshua - Reflections to Peer Responses

 * Shawn: Thanks for the suggestion, integrating them is something I will for sure do.
 * RIley: I agree that the phrasing is somewhat vague and is definitely something I will address in the near future. I wanted to add citations in a later draft, but I see now that I should have just added them in the first one. Adding a picture of the thyroid (if I can find it!) is something I planned on doing.
 * Joe: Citations, as stated previously, are a point of emphasis. I'll have to ask you how you would rephrase it, but I see what you're saying!
 * Grant: Commenting on the skeletal system would be a good addition to my draft, I agree. Thank you!
 * Andrew: My plan was to just focus on the musculature of the external gills and the thyroid gland, but as I continue to research, perhaps it would be a good idea to look deeper into other internal mechanisms of paedomorphosis in the mudpuppy. Looking at the benefits of not possessing a parathyroid gland was an avenue I had not thought of, and will definitely keep it in consideration as I move forward in the drafting process. Killer points, dude!
 * Lexie: Yes, the intent was to post my edit on the salamander page! I will be sure to keep an eye out for if there are any replacement organs for the parathyroid gland.
 * Liz: My first draft is very rough, surely, but your points are appreciated. As I go further into the draft process, I will definitely make sure that the language does not become too advanced for the general Wikipedia audience. I will definitely have to go over the Wikipedia tutorials on adding images, as that was something I planned on doing. Thank you for your input!
 * Chris: Thank you for your comment!
 * Blanca: I will cross reference the extent to which salamander skeletons are touched upon in the more general pages (amphibian, etc.) to see if there would be merit it adding skeletal information to the salamander page. Advantages or disadvantages to the presence/absence of the parathyroid gland tie in nicely with the current function/lack thereof in reference to the thyroid in mudpuppies, so I will be sure to keep this is mind as I move forward in the drafting process!

3/17/2017: Draft 1 of Article Addition

 * The Salamander page, under its section about description, only lists a section concerning the "trunk, limbs and tail," and contains no anatomical information on anything skeletal, or relating to organs. This section could be broken up into external and internal features, with external features focusing on the skeletal and organ-related specifics to salamanders.
 * Most salamanders have both thyroid and parathyroid glands; the common mudpuppy does not have a parathyroid gland . The thyroid gland in some salamanders, like the Axolotl, produce normal thyroid hormones, but cells in the organism express thyroid hormone receptors (TR) that are mutated, and do not bond correctly with thyroid hormones, leading to some salamanders in a state of perpetual juvenile-hood.

Useful Citations
Gill Musculature Terminology

Axolotl Thyroid Research

3/3/2017: Assignment to Group Dissections
Three organisms of interest:

Microbat- seeing the homologous structures that are present in a bat and how they differ from that of other animals that fly

Thing(s) to possibly edit: Iguana- Intermediary tetrapod; seeing the differences/similarities of reptiles between amphibians and mammals
 * Larynx
 * Gill
 * Inferior colliculus

Thing(s) to possibly edit: Proteidae- Has both lungs and gills; am interested in how those two function and relate to each other
 * Parietal eye
 * Tympanum (anatomy)
 * Hemipenis

Thing(s) to possibly edit:
 * Gill
 * Operculum (fish)
 * Olm

Final Deuterostome Talk Page Addition:
Possible Content Edit;

Combining 'Classification History' section with 'Classification' section. Unnecessary to have two sections separate from each other, as well as in different places of the Wikipedia article. The section containing 'Notable Characteristics' would be a better first section to have listed after the introduction, as it defines what Deuterostomes are and how they are all related to each other. A way to implement both of these changes could be seen as how the Chordate section and subsections are organized.

Also, the section on the 'Formation of the Mouth and Anus' could also be included as a subsection of 'Notable Characteristics' as it is already commented upon first in that section. A way to implement both of these changes could be seen as how the section and subsections are organized.

Deuterostome Article Review Notes

Is the New York Times a reputable source for citing for the first citation on the meaning of the word 'deuterostome?'

Could specify which evolutionary trait came first in chordata and hemichordata; the tubular (presumably solid) nerve cord or the (dorsal) hollow nerve cord?

Could have placed the fifth citation at the end of the paragraph of the last paragraph of 'Notable Characteristics.'

No citation for 'Formation of mouth and anus' section

Numerous citations from before 2000; potentially outdated

Formatting for 'Notable Characteristics' section is odd at the end; does Echinoderms really need their own separate paragraph to say that their dorsal hollow nerve cord has probably been lost evolutionarily (which it never explicitly says)?

Talk of early fossils of non-vertebrate chordates not being readily available was slightly distracting.

Says most deuterostomes display indeterminate cleavage, but makes no mention of any that do not