# Talk:Heterochrony

This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Kenneth.leep. Peer reviewers: Leahc 10.
Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 23:24, 16 January 2022 (UTC)

Intent to update and flesh out the data in the lead, in paedomorphosis, and in human heterochrony. For example, in human heterochrony, there is mention of "30 neotenies" identified in humans compared to chimpanzees, without identifying specifics or how these were determined. Likewise, the paedomorphosis section does not provide adequate information or intra-wiki links to support the section's usefulness. — Preceding unsigned comment added by Kenneth.leep (talk • contribs) 18:11, 24 January 2017 (UTC) 

Hi there, and good luck. I guess you know the lead is meant as an (uncited) summary of the cited material in the body, so it shouldn't introduce anything new. I'm not convinced that detailing 30 aspects in humans is wise - that sort of detail would be for the article 'Neoteny in humans', but a cited mention and a few details would be fine. Chiswick Chap (talk) 18:43, 24 January 2017 (UTC)
I wasn't planning to go into all 30 of them in any kind of detail. I just felt it was odd to mention a specific number and then not detail any of them, so I figured I'd do something like a "such as" and mention two or three, with a list of citations where more could be found. Or, as you say, links to other articles where a more complete list can be found. Thanks for your input! Kenneth.leep (talk) 20:49, 25 January 2017 (UTC)

Hi. I bring this up because I removed a sentence in the article and wanted to explain. There was an uncited claim that "Paedomorphic species are mainly aquatic, while peramorphic species are mainly terrestrial." which I see two problems with. First (and easiest), I doubt that this has ever been tested. If it has then it should have a citation; if not it should probably be removed. Even if an author has stated this, if it has not been evaluated, we shouldn't echo it here. Second, even if it has been tested in the sense of "things that look paedomorphic" are found in water, it is almost always confusing, or just incorrect, to refer to a species (or genus etc.) as being paedomorphic. Heterochrony acts on the different parts of the organism differently (as in the Irish Elk example). If what is being referred to here is something that covers the whole body such as the end of deterministic growth or sexual maturity, then that should be referred to. Changes in developmental timing are very rarely a total on/off switch, which is why the idea of Humans as big babies has been mostly abandoned (we are paedomorphic in some important ways but peramorphic in others). This may seem nuanced, but heterochrony is complicated and I think it's worth it to tinker with potentially misleading parts of the article. -Paleoaskari (talk) 00:20, 25 April 2018 (UTC)

The sentence was not based on the cited source, and looks like a simple piece of WP:OR. Chiswick Chap (talk) 02:51, 25 April 2018 (UTC)

@Chiswick Chap: When you added the stuff about Walter Garstang's suggestion, you presented it in such a way that readers might believe the tunicata origin of vertebrates to be an established fact.  However, neither the few articles and books I've seen treating this, and nor the source that you gave actually claims this.  (McNamara actually writes that Garstang suggested this, but I found no claim of his that this suggestion is correct or even a majority opinion.)  Moreover, e. g., the phylogeny given in Chordates (grouping vertebrates and tunicates within the clade Olfactores, with the lampreys as an 'outgroup') is hard to reconcile with Garstang's hypothesis.  I rewrote this as precisely an hypthesis, still held by some biologists, but not by a consensus.  Do you find this reasonable, or do you have other reliable sources in favour of Garstang's hypothesis? JoergenB (talk) 20:56, 13 July 2021 (UTC)

If I got the source wrong, I'm sorry; gave it my best shot. Happy that you've done your best with the additional material. Chiswick Chap (talk) 07:25, 14 July 2021 (UTC)

This review is transcluded from Talk:Heterochrony/GA1. The edit link for this section can be used to add comments to the review.
Reviewer: Jens Lallensack (talk · contribs) 19:17, 15 January 2022 (UTC)

Reading now. --Jens Lallensack (talk) 19:17, 15 January 2022 (UTC)

first sentence: Maybe provide more links (e.g., developmental process) so that the reader can access very basic biology articles needed for understanding?
Added.
Citations not needed in lead here; should be repeated in text.
Moved.
He assumed that embryonic development (ontogeny) of "higher" animals – "He" is Haeckel, not Gould, right?
Yes.
paedomorphosis (neoteny) – link at first mention in main text?
Done.
and suggested that the vertebrates arose – not sure, but is the "the" too much?
Brit.
"higher" animals recapitulated their ancestral development (phylogeny). – Maybe an example could be helpful here, e.g. the gill-like structures in human embryos?
Added.
De Beer anticipated evolutionary developmental biology in his 1930 book – I think this might be missing some context on evo-devo. When was this field established, and what role did heterochrony play? If you think this is out of place here, I would alternatively suggest to replace/reword "anticipated evolutionary developmental biology" since it may not be accessible without the background knowledge.
Added.
In 1928, the English embryologist Walter Garstang showed that tunicate larvae shared structures such as the notochord with adult vertebrates, and suggested that the vertebrates arose by paedomorphosis (neoteny) from such a larva.[9] – This could do with an additional sentence clarifying the significance of this. Which particular general concept was first established here?
Added a gloss.
Intraspecific heterochrony, Interspecific heterochrony, paedotypic etc – need redirects to this article?
Why not, feel free. Not a GA matter.
Ambystoma talpoideum, metamorphosis – link?
Linked.
Reilly et al – lacks a dot, but I would suggest "and colleagues" to make this article more accessible
Done.
Section "Paedomorphosis" – it does not become quite clear how to tell apart neoteny and progenesis. How do we determine that Axolotls show progenesis rather than neoteny? Do they simply become sexually mature more quickly compared to their ancestors? Maybe this could be stated for clarity.
Glossed.
Paedomorphosis may play a critical role in avian cranial evolution.[35] – and is this an example of neoteny or progenesis?
Progenesis.
up to 12 feet wide – SI units should be preferred here, maybe with conversion
Convert-ed.
its close relative the moose – needs comma and link?
Done.
Insular rodents have evolved these features to accommodate the abundance of food and resources they have on their islands. – link to Foster's rule?
Linked.
The mole salamander, a close relative to – are you indeed referring to the genus as a whole here, as linked?
Species linked.
in the Puerto Rican Tree frog. – also here, link needs to be more precise.
Local species group linked.
Population density, food, and the amount of water may have an effect on the expression of heterochrony. – How does this relate to developmental plasticity? Maybe that term should be mentioned under "related concepts"?
Well, like you I presume it's implied, but we'd best stay with what's stated.
and it was much in favour for many years,... . – Excessive punctuation?
Direct quotation.
Yes I know, but you use the ellipsis to indicate you left something out. Why, then, not simply leave out the "," and the "." as well? As is, it looks a bit chaotic. --Jens Lallensack (talk) 22:15, 15 January 2022 (UTC)
Done.
— Richard Dawkins, The Ancestor's tale (first edition, 2004), Rendezvous 24, Sea squirts – This quote seems to need an inline citation instead of providing the book title directly, with page number.
Cited.
That's all! Nice overview article. --Jens Lallensack (talk) 21:16, 15 January 2022 (UTC)
Thank you!
Looks good, promoting now. But see one reply above. --Jens Lallensack (talk) 22:15, 15 January 2022 (UTC)
Many thanks, removed the stray punctuation. Chiswick Chap (talk) 22:24, 15 January 2022 (UTC)

I think the photo of the three recent giraffes is inappropriate, because it reminds one of the giraffe example that is always used when the theories of Lamarck and Darwin are compared. However, in the comparison of these theories it shows a recent giraffe and its ancestors with shorter necks. Here, in this photo, you see three recent giraffes of completely the same build, which are probably of different ages, are of different sizes due to their sex, and appear to be of different sizes due to the perspective. This has nothing to do with heterochrony. We should find photos with examples in which animals look different due to different developmental processes of the same organs. Sciencia58 (talk) 06:27, 12 February 2022 (UTC)

Do you. What to say? – adding 3 images to the lead where MOS says 1 isn't great; that they had essay-length captions not cited anywhere and not even mentioned in the text is a really bad look; and the original lead image caption is correct, cited, and nothing whatever to do with Lamarck (indeed the article isn't either, the subject is control of development, and the remarkable growth of the neck-bones is discussed in the article).  I won't sprinkle any upper-case acronyms around here, but other editors would know what they'd call it.
If you feel like adding a properly-cited discussion with image to the article text, that ought to be ok, but I would like to caution that the article carefully avoids the "and another example of the same thing is found in the lesser-spotted bush frog[1][2][3][4][5]" paradigm, which quickly dissolves into random list-cruft and student-on-assignment-paragraph-dumpitis. Any addition, in other words, must earn its keep by illustrating something new to the article: that process must be explained as well as illustrated and cited. Hope this is clear. Chiswick Chap (talk) 08:59, 12 February 2022 (UTC)
Which one of the three giraffes is the embryo????? What about their legs? Why are they so long?
The article describes some cases of heterochrony in indivduals and the species they belong to.
In the introduction it says: "In evolutionary developmental biology, heterochrony is any genetically controlled difference in the timing, rate, or duration of a developmental process in an organism compared to its ancestors or other organisms." There were no images comparing species belonging to different taxa, although these relations are relevant too. Instead there are three morphologically identical giraffes as cover-photo and giraffes in the paragraph "inter-specific" heterochrony. Some examples with images for interspecific comparison would be important for easier understanding of the topic. At the moment, the illustration gives the wrong impression that the term heterochrony only refers to processes within an individual.

 Sciencia58 (talk) 12:34, 12 February 2022 (UTC)
Hm, I'm really not impressed by this sort of discussion. Let's wait and see what other (uncanvassed) editors think. Whatever we may choose to do, it's not going to consist of randomly-chosen and uncited images and text unrelated to the cited text. Chiswick Chap (talk) 15:16, 12 February 2022 (UTC)
Heterochrony in evolution Sciencia58 (talk) 15:45, 12 February 2022 (UTC)
Lamarckism
Lamarckismus Sciencia58 (talk) 16:59, 12 February 2022 (UTC)