Talk:Evolution of mammals

From Wikipedia, the free encyclopedia

	Evolution of mammals is a former featured article candidate. Please view the links under Article milestones below to see why the nomination failed. For older candidates, please check the archive.
April 19, 2008 Featured article candidate Not promoted

This article is within the scope of the following WikiProjects:

WikiProject Evolutionary biology (Rated B-Class) This article is part of WikiProject Evolutionary biology, an attempt at building a useful set of articles on evolutionary biology and its associated subfields such as population genetics, quantitative genetics, molecular evolution, phylogenetics, evolutionary developmental biology. It is distinct from the WikiProject Tree of Life in that it attempts to cover patterns, process and theory rather than systematics and taxonomy. If you would like to participate, there are some suggestions on this page (see also Wikipedia:Contributing FAQ for more information) or visit WikiProject Evolutionary biology. B rated as B-Class on the assessment scale High rated as high-importance on the assessment scale WikiProject Mammals ;     (Rated B-Class) Mammals Portal This article is within the scope of WikiProject Mammals, a project to improve Wikipedia's articles on Mammal-related subjects. Please participate by editing the article, and help us assess and improve articles to good and 1.0 standards, or visit the wikiproject page for more details. B This article has been rated as B-class on the quality scale. Top This article has been rated as top-importance on the importance scale. Assessment comments This article has been rated for quality and/or importance but has no comments yet. If appropriate, please review the article and then leave comments here to identify the strengths and weaknesses of the article and what work it will need.

[edit] older entries

Epipubic bones also found in males, both with and without pouches.

[edit] Kudos!

Very impressive article, folks - one of the best I've seen on Wikipedia in the last year or so. Thanks! -- Writtenonsand (talk) 13:18, 17 November 2007 (UTC)

[edit] Evolution as "experimenting". Tweak?

"Multituberculates ... are a fine example of how evolution was "experimenting" in the Mesozoic." --- I suggest that we tweak this sentence, as IMHO even with the scare quotes on "experimenting" it tends to re-inforce the popular misconception that evolution is conscious or teleological rather than stochastic. -- Writtenonsand (talk) 13:34, 17 November 2007 (UTC)

I certainly don't want to encourage misconceptions that evolution is conscious or teleological. But I couldn't think of an alternative phrasing which was not much longer, and the article is rather long already. If you can think of an alternative that adds no more than a handful of words to the length, that would be good.Philcha (talk) 16:41, 17 November 2007 (UTC)

[edit] Section "Expansion of ecological niches" - add further taxonomic clarification?

The section Expansion of ecological niches in the Mesozoic lists "mammaliforms and true mammals" -- I suggest that we add in a note on the relevent order for each item listed, in order to give readers a better sense of the taxonomic picture. E.g., "Castorocauda (order Docodonta), which lived in the mid Jurassic ..." -- Writtenonsand (talk) 13:44, 17 November 2007 (UTC)

I'm not happy with this idea as it would increase the length and complexity of a long, complex article. IMO: the general reader doesn't need it and wouldn't understand it; specialists know the taxonomic context already; intermediate readers can get the taxonomic context from the linked articles on the animals mentioned.Philcha (talk) 16:44, 17 November 2007 (UTC)

[edit] clade template

Great article! Have you ever used the Clade template before? It'll preserve formatting of the cladograms regardless of page size or resolution, and it looks cleaner because it's not set aside in a box, with individual "---"s. For comparison, here's your first tree:

--Tetrapods--------------------------------------------------
      |
      +-- Amphibians ---------------------------------------
      |
      `--Amniotes-----
             |
             +--Sauropsids------------------------------------
             |
             `--Synapsids------
                    |
                    `--Pelycosaurs----
                           |
                           `--Therapsids-----
                                  |
                                  `--Mammals------------------

And here is a quick conversion to Clade template:

If you're interested, I could convert them for you (not right now, though), or if you'd like to do them yourself, I have a few examples here. J. Spencer (talk) 15:21, 17 November 2007 (UTC)

Intersting idea. I tried reducing the browser window width and your clade template behaved better than the "ASCII art". How would it work for something more complex, e.g. Fossil-based_family_tree_of_placental mammals? Philcha (talk) 16:54, 17 November 2007 (UTC)

Hmm... the extra information makes it look trickier, but I'll give it a shot. J. Spencer (talk) 00:15, 18 November 2007 (UTC)

How's this? I had to flip some clades to make the appearance better, so the order is not exactly the same.

J. Spencer (talk) 02:02, 18 November 2007 (UTC)

Thanks for trying, but I prefer to stick with the "ASCII art". I run my screen at 800x600 because I have poor eyesight, and at 800x600 the template causes a lot of horizontal scrolling. With the "ASCII art" one can mitigate that by reducing the insets. Is there any way to reduce horizontal scrolling when using the template? Also in this particular case I find the "ASCII art" version easier to read because most modern mammals are descended from the Epitheria.

I've just had a rather wild idea, which I'm surprised I didn't think of before. Could cladograms be represented by expandable / collapsible trees, similar to those used for folders by Windows Explorer and many email programs? The same approach is also used in some Web pages, using DHTML. Could that be made to work in Wikipedia, and would it be acceptable? Philcha (talk) 18:18, 21 November 2007 (UTC)

I have no clue how one would include DHTML, but if it could be made to work (the now-absent Josh Grosse created the clade template), I don't see why not. J. Spencer (talk) 22:36, 21 November 2007 (UTC)

I've posted the suggestion at Wikipedia talk:Village pump (proposals) Philcha (talk) 16:32, 24 November 2007 (UTC)

[edit] Lactation / suckling and neck ribs

Someone added to the section "Lactation"

This is an interesting idea, but the way it is currently presented has major weaknesses:

• No citations.
• Ambiguity. Would neck ribs prevent the mother from producing milk or the baby from taking it? I expect the latter but then the phrasing could be a lot clearer. I'd also like more explanation of why neck ribs are such an obtacle.
• Logic. If correct, the presence of neck ribs would imply no suckling but absence of neck ribs would no imply suckling - in fact one would expect to find (eventually) transitional forms with no neck ribs but without suckling.
• Position - at present it breaks the flow of the text.

I hope the person who added this material will respond here or by editing that part of the article. Otherwise I'll remove it in 2 weeks. Philcha (talk) 14:56, 15 December 2007 (UTC)

I've removed the remarks about neck ribs. Philcha (talk) 18:12, 29 December 2007 (UTC)

[edit] Great work!

Great work, Philcha! My compliments, you assembled a great article! DaMatriX (talk) 00:00, 22 December 2007 (UTC)

Agreed. May I make a suggestion that the article Evolution of mammalian auditory ossicles could use some of the same hand. Especially, the drawings of the jaw-to-middle ear transitional forms. TomS TDotO (talk) 11:20, 29 February 2008 (UTC)

[edit] Hair/fur helping mammals survive K-T extinction

I've removed from the end of "(earliest evolution of) Hair / fur" the following sentence: "The possession of such insulation is thought to be one of the several reasons that mammals triumphed the K-T extinction." It provides no refs to support it, and I've never seen any such suggestion from a credible source. Philcha (talk) 18:35, 29 December 2007 (UTC)

[edit] Timeline

To improve accessibility, could we have a timeline similar to {{Permian graphical timeline}} in the article? This would give an overview of development of key features with approximate dates, and would be more meaningful for readers who aren't familiar with the eras and their dates.-gadfium 20:21, 14 April 2008 (UTC)

[edit] Good article nomination

This article ought to be nominated at Wikipedia:Good article nominations. Cheers! Wassupwestcoast (talk) 01:07, 19 April 2008 (UTC)

[edit] Placenta

There is a press release which reports about research on the origins of the mammalian placenta. Should something about this be included as one of the distinctively mammalian features which evolved?

Stanford University Medical Center (2008, April 17). Clues To Ancestral Origin Of Placenta Emerge In Genetics Study. ScienceDaily. Retrieved April 19, 2008, from Clues To Ancestral Origin Of Placenta Emerge In Genetics Study TomS TDotO (talk) 13:13, 19 April 2008 (UTC)

Perhaps, if we can get the peer-reviewed article and it actually covers the same ground ("news" articles often contain off-the-cuff comments and personal opinions that the researchers did not include in the the peer-reviewed article). The news article is wrong on at least 1 point, where it says, "the placenta initially evolved through repurposing genes the early mammals inherited from their immediate ancestors when they arose more than 120 million years ago." If these genes are "in common with birds and reptiles" they were inherited from the last common ancestor of mammals and reptiles (possibly a basal amniote) over 320M years ago.

Please keep suggesting things! It's like football (soccer or gridiron) - most moves break down, but eventualy you SCO-O-O-O-O-ORE. Philcha (talk) 14:54, 19 April 2008 (UTC)