Talk:Fern/Archive 1

Archive 1

Archive 2

[Untitled]

The image is perfectly good, but there are still serious problems with the way the servers handle replacement images. I will reload this image later if it does not clear up - Marshman 04:54, 21 Feb 2004 (UTC)

I think is good add the fossil register in the article: http://www1.akira.ne.jp/~unzen/pteridophyta.jpg How I can do the upload? - Aurélio A. Heckert 12:42, 15 Jan 2005

Fly repellant

I live in Italy and my Italian neighbours have taken to hanging fern outside and inside their houses. They tell me it is acts as a fly repellant. Can anyone enlighten me on their claims?

Cheers

Phil

Phylogenetic relationships

A classification of the ferns based on DNA analysis (see Hasebe et. al."Fern Phylogeny based on rbcL Nucleotide Sequences", American Fern Journal 85(4) (1995) 134-181) might look somewhat like the following:

• Division Pteridophyta
  • Class Marattiopsida
    • Order Marattiales
    • Order Christenseniales
  • Class Pteridopsida, Leptosporangiate ferns
    • Subclass Osmundopsida
      • Order Osmundales (the flowering ferns)
        • Family Osmundaceae
    • Subclass Gleicheniopsida
      • Order Gleicheniales (the forked ferns)
        • Family Gleicheniaceae (the filmy ferns)
        • Family Cheiropleuriaceae
        • Family Dipteridaceae
        • Family Matoniaceae
      • Order Hymenophyllales
        • Family Hymenophyllaceae
      • Order Hymenophyllopsidales
        • Family Hymenophyllopsidaceae
    • Subclass Pteridopsida
      • Order Schizeales
        • Family Schizeaceae
      • Order Marsileales (Hydropteridales)
        • Family Marsileaceae
        • Family Azollaceae
        • Family Salviniaceae
      • Order Cyatheales (the tree ferns)
        • Family Cyatheaceae
        • Family Dicksoniaceae
        • Family Lophosoriaceae
        • Family Loxomataceae
        • Family Metaxyaceae
        • Family Plagiogyriaceae
      • Order Orthiopterales
        • Family Orthiopteraceae (Dennstaedtiaceae Group 4, Orthiopteris)
      • Order Lindsaeales
        • Family Lindsaeaceae (Dennstaedtiaceae Group 3, Lindsaea and Sphenomeris)
        • Family Lonchitaceae (Dennstaedtiaceae Group 2, Lonchitis)
      • Order Pteridales (incl. Pteridaceae and Vittariaceae)
        • Pteridales Family 1: Onychium, Platyzoma, Pteris, Taenitis
        • Pteridales Family 2: Acrostichum, Ceratopteris
        • Pteridales Family 3: Argyrochosma, Bommeria, Cheilanthes, Doryopteris, Hemionitis, Notholaena, Pellaea
        • Pteridales Family 4: Coniogramme
        • Pteridales Family 5: Adiantum and the Vittariaceae
      • Order Dennstaedtiales
        • Family Dennstaedtiaceae (Dennstaedtiaceae Group 1, Blotiella, Dennstaedtia, Histopteris, Hypolepis, Microlepia, Paesia, Pteridium)
        • Family Monachosoraceae
      • Order Polypodiales
        • Family Aspleniaceae
        • Family Blechnaceae
        • Family Davalliaceae
        • Family Dryopteridaceae (polyphyletic family)
        • Family Grammitidaceae
        • Family Lomariopsidaceae
        • Family Nephrolepidaceae
        • Family Pleursoriopsidaceae
        • Family Olandraceae
        • Family Polypodiaceae
        • Family Theypteridaceae

Families Hymenophyllopsidaceae and Lophosoriaceae were not sequenced in the study, and are placed above based on morphogenic relationships identified by others. The study found families Dennstaedtiaceae, Pteridaceae, and Dryopteridaceae to be polyphyletic. The families in Order Polypodiales could probably be grouped into monophyletic suborders. Tom Radulovich 07:04, 19 May 2004 (UTC)

Classification, definitions...

Where's the classification in the pteridophyte entry from? It's not similar to anything being used in recent floristic works on pteridophytes such as the treatment in the Flora of North America or Pteridophytes of Mexico, and looks to me like there's a lot of unnecessary and confusing splitting at the order and family levels. I'd suggest that a conservative classification based on taxa that are recognized in floristic works would be much more useful... if we want to base things on recent gene trees we can give a different classification for every paper published, which accomplishes nothing.

FWIW, I've started a bit of modification on the families... I'm wondering if anyone has thoughts on order/subclass type stuff; the large amount of higher-level division in the currently-listed classification only makes sense given a high level of family-level division (e.g., otherwise most of the orders are monotypic), which (IMO) doesn't make sense given the current lack of well-supported groups at the family level. But I haven't been keeping track of recent papers enough to know what order/subclass divisions other people are using. Paalexan 22:48, 18 November 2005 (UTC)

There is the one at the top of this page - Marshman 02:05, 19 November 2005 (UTC)

I know... but that's 1995. I'm assuming more's happened since then. I guess I'll have to go wander the literature... Paalexan 19:13, 20 November 2005 (UTC)

Looks like there aren't any more recent analyses that improve on Hasebe et al., so far as I can tell. Also worth mentioning that Hasebe et al. don't worry at all about higher-level nomenclature and simply list previously used family names rather than revising anything at the family level. The result is that a number of different ordinal and familial classifications are consistent with their analyses, and since it's only a single-gene phylogeny with poor support for a lot of the nodes, it seems unwise to draw general conclusions from it... Paalexan 21:30, 20 November 2005 (UTC)

I'm also baffled by this:

"Two related groups of plants, commonly known as ferns, are actually more distantly related to the main group of "true" ferns. These are the whisk ferns (Psilophyta) and the adders-tongues, moonworts, and grape-ferns (Ophioglossophyta). The Ophioglossophytes were formerly considered true ferns and grouped in the Family Ophioglossaceae, but were subsequently found to be more distantly related."

I'm not aware of any recent publications that show Ophioglossaceae and Psilotaceae as anything other than ferns. The view that they were separate is the older view that has been contradicted by more recent genetic evidence, not the other way around!

The Psilotaceae is regarded as a fern ally family (Palmer, 2003). Not sure where that fits in - Marshman

? Which paper is this? I'm also not sure what you're meaning by "fern ally"; the term is often used to refer to the equisetophytes and lycophytes, but doesn't have too explicit a meaning... - Patrick Alexander

Palmer, Daniel D. 2003. Hawai`i's Ferns and Fern Allies. Palmer is student of Herb Wagner. He admits that fern taxonmy is complex and controversial and far from settled. But he defines fern allies as: "distinct evolutionary lines with no close affinities and....only distantly related to ferns." Certainly that fits the Psilotaceae. He includes the Ophiglossaceae as a fern family - Marshman 23:00, 15 November 2005 (UTC)

Ah. I'd been thinking you meant J.D. Palmer, who's done a couple of papers involving phylogeny of all plants. I'm not sure why D.D. Palmer defines things as he does in that book (which I have, BTW, and which is excellent for IDing Hawaiian ferns). Genetic phylogenies I'm aware of all place Psilotaceae and Ophioglossaceae as sister taxa basal to the rest of the ferns. Calling the two of them together a separate division is compatible with phylogeny, but just seems like pointless splitting to me. Paalexan 19:21, 16 November 2005 (UTC)

Then you can see he does avoid committing to a higher taxonomy (nothing above the family). Yes, an excellent book for taxonomy. - Marshman

There are also a bunch of problems with definitions of "fern", etc. E.g., all plants reproduce by spores and have alternation of generations, so introducing these as distinguishing characteristics of ferns is misleading. Also, absence of seeds only gets you halfway there, since lycophytes and equisetophytes also lack seeds. And then rhizoids are referred to as stems, which is simply incorrect. - Patrick Alexander

Disagree with "all plants have alternations of generations". Aside from the fact that that terminolgy is not much used anymore (as it is incorrect), by some definitions the "A of g" refers to independent stages. Seeds - right, but an important distinction none-the-less. Rhizoids on the prothallus s/b root-like structures. - Marshman

As far as I'm concerned, alternation of generations just refers to both the diploid and haploid stages being multicellular. Either way, the term isn't particularly relevant and the important thing is that all plants have diploid sporophyte and haploid gametophyte stages that are multicellular, and the differences between them are in the relative sizes, forms, and trophic abilities of the gametophytes and sporophytes and in level of differentiation within gametophytes (i.e., pollen & ovules vs. bisexual gametophytes). Worth mentioning in that regard that Marsileales shares highly-reduced, short-lived male and female gametophytes with the seed plants... Paalexan 19:21, 16 November 2005 (UTC)

Very interesting. I think there is more than one concept of "alternation" out there, and I lean more towards the "free-living" distinction, but all types intergrade and I like the way you put it. Can I move that over to the article alternation of generation? - Marshman 20:16, 16 November 2005 (UTC)

Feel free to move things over to the alternation of generations article. 128.123.94.172 21:38, 16 November 2005 (UTC)

You can certainlty start making corrections/changes. If sources are not given, I'd suggest adding some. Usually a page like this grows by inputs from lots of people, so you may be questioned, but charge ahead and be ready to support your changes. By the way, the best way to start any serious editing is by setting up an account at Wikipedia. It is very easy - Marshman 21:16, 15 November 2005 (UTC)

Yeah, I've set up an account. I just figured it might be better to start by posting stuff on here rather than do major changes and then have everything changed back if there're people committed to the current setup. - Patrick Alexander

Good strategy. You can sign your replies with a row of 4 tildes ~~~~ and your screen name at the date/time stamp will be appended automatically - Marshman

Well, now I've messed with things a little. I might do more later, like adding pages with general definitions of sporophyll & trophophyll, discussion of variation in them between plant groups, etc... Thanks for letting me know about the 4-tilde thing, seems useful. Paalexan 19:21, 16 November 2005 (UTC)

Excellent rewrite. Clarifies things tremendously. I note you deleted the term "prothallus". Is it no longer used?

Be a bit cautious adding pages (articles) that are nothing more than definitions. One rule around here is "Wikipedia is not a dictionary"; Wiktionary is, however. Best to incorporate definitions of scientific terms within an article with a broader context (need not be one as general as "ferns" of course). - Marshman 20:16, 16 November 2005 (UTC)

Regarding "prothallus"--AFAIK it's synonymous (or nearly enough so that it doesn't really matter) with just "thallus". I noticed both were used in the article without distinction, so just simplified things by changing it to only using one. And, yeah, if I add pages for sporophyll & so forth it'd be with the idea of saying something about the kind of important variation in them, how that relates to major plant groups, etc., rather than just a definition. 128.123.94.172 21:38, 16 November 2005 (UTC)

And when you log in (don't forget; that is why the tildes have only an IP address) check the "remember me" box. Most of the time, you will be recognized and not need to log in each session - Marshman 21:46, 16 November 2005 (UTC)

My books use 'prothallus' for these; two give different definitions in their glossaries:
Prothallus: (1) The gametophyte generation of ferns and other cryptogams, a delicate liverwort-like structure bearing the antheridia and archegonia on its lower surface and providing a site for the fusion of gametes and development of the sporophytes generation. (2) A small plate of tissue derived from a spore and bearing male and female reproductive structures.
Thallus: (1) An undifferentiated vegetative growth. (2) A plant body not differentiated into leaf, stem and root.
I think we'd do better to use 'prothallus'? - MPF 10:02, 17 November 2005 (UTC)

Yes; I was going to add it in since it is a word encountered in books, etc. so its complete removal could leave some reasders wondering. Can we put those defs up on Wiktionary ? Suitably reworded to avoid copyright violations - Marshman 17:52, 17 November 2005 (UTC)

Prothallus it is, then. By the definition "2" for "Thallus" (which is the definition of the word I'm familiar with), the gametophytes of most ferns are thalli (as well as prothalli!); but "prothallus" seems to be more often used for fern gametophytes (whereas, for whatever reason, "thallus" seems to be used more often for liverworts, though they don't differ from fern gametophytes in ways that are, AFAIK, relevant to the definitions). Paalexan 20:48, 17 November 2005 (UTC)

vegetative propagation

when a ferns' rhizomes spread, can they grow a new independent fern? Also, we could use a picture of the prothallus Lotusduck 20:34, 15 December 2005 (UTC)

Yes, a property that is held by a majority of plants as most have open growth. Any plant that roots as it spreads or can be chopped apart and have the parts root can be separated into "independent" plants, but that is nothing special or unusual in the plant kingdom. Lacking a centralized nervous system, the idea of "independent" is perhaps the hang-up - Marshman 20:50, 15 December 2005 (UTC)

I get the impression that ferns are very poor outcrossers. Each prothallus must be wet enough to be fertilized by motile sperm, and if the prothallus is monoecious, then it just self fertilizes almost every time. If it's diecious, then I can't imagine it getting fertilized very often at all. It's kind of hard for me to wrap my head around this prothallus thing, since most archegonium and antheridium are well positioned for transport of genetic material, and the prothallus is on the ground and needs water, and will most probably self. Because of all this weirdness, I rather think there should be a wikipedia article on the prothallus, except at the moment I am too confused to start it.

Maybe later I will not be so. Lotusduck 14:19, 16 December 2005 (UTC)

Well, there certainly are a number of interspecific crosses reported for ferns, so something is going on. Also, because the spore allows for the potential production and distribution of millions of prothalli, in environmentally friemndly locations the prothalli are likely to be gill to tooth (very crowded), encouraging lots of exchange movement of motile sperm - Marshman 18:46, 16 December 2005 (UTC)

wow

Images?

Just posted an image of fern spores, but I don't really know how to identify this fern. Help! Anca 07:09, 29 August 2006 (UTC)

Post a query on the WP:PLANTS talk page. Some sort of basic description of the whole plant would help, e.g. total height of the plant, length of the fronds, etc - MPF 08:58, 26 October 2006 (UTC)

On images for the whole page, it seems to be getting used as a dumping ground for photos of unidentified ferns. There are now numerous photos on commons of identified species; I propose to remove all the un-named photos, and replace them with a selection of named species showing more of the diversity of structure of different ferns - MPF 08:58, 26 October 2006 (UTC)

Totally agree. What would be more useful would be some photos of typical life stages - i.e. close up of a sorus, prothallus etc. Mrs Trellis 09:53, 26 October 2006 (UTC)

Nice idea, if we have any pics of them! I'll take a browse through commons to see what there is - MPF 13:13, 26 October 2006 (UTC)

There is one here that might be possible. Mrs Trellis 14:09, 26 October 2006 (UTC)

Prothallus

Classification, revisited

Still no reference, source or citation in the article for the classification scheme being followed for ferns? All classification schemes are opinions, and fern classifications even more so than most. Despite recent molecular advances and clarifications, fern taxonomy is still a horrendous mess and you would be hard-pressed to find two pteridologists who agree on any one classification. This classification presented here is somebody's opinion, i.e., POV, so whose? MrDarwin 19:08, 24 August 2006 (UTC)

I think a modern approach is the followed by Judd et al. (2002. Plant systematics: a phylogenetic approach, Second Edition.Sinauer Axxoc, USA.), availed by Pryer et al. in the 2004 paper ("Phylogeny and evolution of ferns (monilophytes) with a focus on the early leptosporangiate divergences." American Journal of Botany 91:1582-1598). 200.43.74.219 21:50, 17 October 2006 (UTC)

The recent classification of Smith et al. 2006 is now references in the article, but as far as I can tell nobody has updated the unreferenced classification scheme presented in the article to reflect it--I hope somebody will eventually have the time to get around to it. MrDarwin 20:34, 28 December 2006 (UTC)

I've just made a major edit to the classification section to reflect the proposed classification of Smith et al. 2006. While quite new and a major departure from some other classifications, in many respects this is the fern version of the Angiosperm Phylogeny Group classification, as it is authored by several respected pteridologists and is based on numerous molecular systematic studies supplemented by morphological data. Most importantly, it is a referenced and verifiable classification linked to a publshed paper that can be consulted for further information, unlike the rather mysterious one that was used previously. The classification section of this article still needs major work, but I hope this will provide a framework, and encourage other editors to go to the various fern articles and update their classifications. MrDarwin 01:59, 29 December 2006 (UTC)

One additional note: the Smith et al. 2006 classification does not recognize any named taxa above the rank of class, so it may be tricky to accommodate in taxoboxes. For the most part I've avoided editing taxoboxes, especially at the higher ranks--not my cup of tea, so I'll leave that to others. But in looking through the various fern and "pteridophyte" articles and taxoboxes I've found quite a bit of inconsistency in classification, with the text and taxoboxes in numerous articles contradicting each other. MrDarwin 14:08, 29 December 2006 (UTC)

References

Should references not be noted in the Text? Osborne 12:28, 15 February 2007 (UTC)

ferns in Spain

Greetings fern lovers, Am doing meatball surgery on a translation Forests of the Iberian Peninsula/Translation and have been surprised that no mention seems to be made in the original article of ferns in Spain. I know for a fact that they exist, at least in Asturias, a damp part of the north of the peninsula, and I'm pretty sure I read somewhere that since the 80s they have been a protected species in this country, together with moss. Can anyone help me out, and if relevant, add the reference to the fern article. Thanx. --Technopat 23:30, 10 February 2007 (UTC)

There are dozens of fern species in the Iberian Peninsula, including rock ferns in the mountains, even in semi-arid areas. I have a field guide to ferns of Spain and Portugal; I'll try to find it. jaknouse 23:47, 13 July 2007 (UTC)

Greetings, Jaknouse. Thanx. Regs.--Technopat 22:38, 5 August 2007 (UTC)

"Blätter des Mann=Waldfarn"

Nature print by Alois Auer

Jurassic Park fern

I cannot find an article for Serenna Veriformans a fern mentioned in Jurassic Park, can any one provide some info, please. 71.81.37.185 —Preceding comment was added at 01:54, 6 November 2007 (UTC)

It's not listed in any of the major paleobotanical texts. It may have been invented by Crichton for his novel. --EncycloPetey 02:23, 6 November 2007 (UTC)

Crichton Rules!!!! —Preceding unsigned comment added by Assassins creed1 (talk • contribs) 03:10, 6 May 2008 (UTC)

Haploid

1. A sporophyte (diploid) phase produces haploid spores by meiosis;
2. A spore grows by cell division into a gametophyte, which typically consists of a photosynthetic prothallus
3. The gametophyte produces gametes (often both sperm and eggs on the same prothallus) by mitosis

(I quote, as a lay ignoramus)

But, but.... the spores are thus haploid but grow by cell division into a gametophyte which is surely diploid if it is to produce two gamete types???? —Preceding unsigned comment added by 81.152.7.211 (talk) 09:15, 22 May 2008 (UTC)

No. All gametophytes of plants are haploid (under normal conditions). Gametes are not produced by meoisis in plants. --EncycloPetey (talk) 13:32, 22 May 2008 (UTC)

Fern Life Cycle

It would be useful to have a section on the life cycles of ferns in this article - does anyone agree? Wriggles1 23:06, 10 December 2006 (UTC)

I diagram would be good 124.171.168.49 (talk) 12:18, 22 June 2008 (UTC)

Classification?

I'm about to begin on the non-magnoliophyte vascular plant articles at Wikipedia in Norwegian nynorsk, and I noticed that Wikipedia in Norwegian bokmål uses a classification which has the clubmosses as a class (Lycopsida) within division Pteridophyta. This is contrary to what I have been taught at uni, and also to the classification used here. There are only two sources for the "offending" article at no.wiki, and one of these is the paper by Smith used for classification in this article. I can't find that they even mention clubmosses, so I assume the info is either unsourced or from the flora mentioned, which I don't have access to ATM. I am not an expert on ferns in any way, so if someone here could give some advice, that would be grand. So far I have operated with the classification used here, although the (very few) articles on individual ferns to be found at nn.wiki use the other one.Hinakana (talk) —Preceding undated comment was added at 01:03, 30 July 2008 (UTC)

The Smith paper does not include the lycophytes in Pteridophyta. There is an outline of the Smith classification available at commons:Smith System. --EncycloPetey (talk) 01:18, 30 July 2008 (UTC)

This paper (freely available) has findings consistent with Lycopsida rather than Lycopodiophyta]Hinakana (talk) —Preceding undated comment was added at 01:35, 30 July 2008 (UTC)

That paper is more than a decade old, and has been superceded by more extensive research. The clade Lycopodiophyta was formally named under the PhyloCode last year as a result of strong multi-gene analyses in this paper: Cantino, Philip D. (2007). "Towards a phylogenetic nomenclature of Tracheophyta". Taxon. 56 (3): E1–E44. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) --EncycloPetey (talk) 04:48, 30 July 2008 (UTC)

"Filicinophyta"?

My Biology textbook calls this phylum Filicinophyta instead of Filicophyta. I'd like to know why Filicinophyta isn't used in Wikipedia in ANY article (search failed to show any result), or perhaps what is/are the difference(s) between these two terms, so as to clear up my confusion. Thanks in advance. — Yurei-eggtart 13:20, 12 March 2009 (UTC)

The term "Filicinophyta" appears to be very, very rare in the literature. I had never heard it before you mentioned it. It appears to be an error. The genus Filix becomes filicis in the Latin genitive singular, and the inflectional ending -is then would be replaced by -aceae / -ophyta, etc., according to the ICBN, to form "Filicophyta". So the reason it isn't included is that it's an ungrammatical error. You should context the publisher of your textbook and ask them to correct it. --EncycloPetey (talk) 20:01, 14 March 2009 (UTC)

Propose merging Monilophyte into Fern

Right now we have a short stub at Monilophyte and a fairly extensive article at Fern. As currently written, both articles cover the same group (that is, including Psilotopsida, Equisetopsida, and Marattiopsida as well as the leptosporangiate ferns). Given the lack of consensus among scientists about the names for each of the groups, and the desirability of having some kind of article at fern, the best term for the combined article would seem to be fern. I believe I am just summarizing a discussion which happened (as a tangent to another merge) at [1], but I wanted to ask before doing the merge, just in case. Kingdon (talk) 21:33, 20 December 2009 (UTC)

My concern is not with the merge, but rather that the current article is mainly about leptosporangiate ferns. That's not especially surprising (iirc, flowering plant is mainly about eudicots and monocots), but the current article uses "fern" to designate a group broader than most non-specialists would expect. I don't have any explicit recommendations, but I'd like to discuss the issue.--Curtis Clark (talk) 22:09, 20 December 2009 (UTC)

My concern is that neither article covers the fossil stem group Cladoxylopsida. However, a merger seems a good idea to me, since both article do cover the same set of taxa. --EncycloPetey (talk) 22:39, 20 December 2009 (UTC)

I'm for a merger, under fern -- under the understanding that the following all redirect there: monilophyte, monilophyta, moniloformopsida (form?), pteridophyta, filicophyta, polypodiophyta. In any case, it's clear that this refers to the fern division, or the monilophyte clade, which is inclusive of all known vascular plants that are not seed plants or lycophytes, plus, of course, fossil forms. jaknouse (talk) 23:21, 20 December 2009 (UTC)

This proposal is just about Monilophyte. Some of the others you mention already redirect here. Kingdon (talk) 03:09, 21 December 2009 (UTC)

Jaknouse, your statement about "inclusive of all known vascular plants that are not seed plants or lycophytes" is incorrect. There are several other clades of vascular plants as well (now extinct, e.g. Cooksonia and the Rhyniopsida), unless I'm misinterpreting your use of "plus". --EncycloPetey (talk) 04:05, 21 December 2009 (UTC)

No, the "inclusive" phrase only applied to extant plants. I didn't want to get into apomorphies or whatever. jaknouse (talk) 04:09, 21 December 2009 (UTC)

I've gone ahead and done this merge (not a formal merge in the sense of bringing any text over, but Monilophyte now redirects here and this article mentions the term monilophyte). Kingdon (talk) 19:37, 28 December 2009 (UTC)

Too much emphasis on leptosporangiate ferns?

In the above section, Curtis Clark (talk · contribs) asks whether the article is too focused on leptosporangiate ferns. On the whole, I think an emphasis on the largest group is fine, but there probably are cases where we could give a brief mention to the other groups, or where we should check whether we are making a claim which isn't true of the others. My ability to work on this (without doing a bunch more reading) is limited, though, as I'm not sure how many of the specific points (especially in the sections Life cycle and Fern ecology) are specific to leptosporangiate ferns. Kingdon (talk) 19:37, 28 December 2009 (UTC)

2 Questions

1)Do all spores (on a single fern) have identical genetic material?

yes

No. The spores are produced by meiosis, which separates homologous chromosomes, resulting in spores that each have half the genetic material of their parent fern, but the particular portion that forms the half varies from spore to spore because the chromosomes are sorted independently. This ought to be discussed on the meiosis article, rather than repeated on every page where it happens. --EncycloPetey (talk) 20:12, 16 May 2010 (UTC)

2)Do gametophytes produce a zygote by fertilising their eggs with their own sperm (as the article implies) or does it happen with the use of neighbouring gametophyte's sperm?

both, some gametophytes have a sort of sex determination in that they have stages of development

Some gametophytes can fertilize their own eggs, but many gametophytes have a mechanism that reduces the chance of this happening or eliminates the possibility. Some fern gametophytes release chemicals that influence the sex of neighboring gametophytes to male, and some gametophytes produce only one type of reproductive organ or the other. --EncycloPetey (talk) 20:12, 16 May 2010 (UTC)

Yep, I know talkpage is not a forum but claryfying these things may improve the article78.131.137.50 (talk) 23:12, 9 February 2010 (UTC)

The Structure section is way off...

The "Stem" section describes two different things, the rhizome (which is not by any defintion a "stem")(Ok, in some definitions, but certainly not all. I've always understood it to be the structure from which the "stem" - or more accurately, the stipe - grows. Perhaps this illustrates why "stem" is not an ideal term here.) and the stipe - which is not mentioned anywhere.

What it describes as a "leaf" is actually a pinna or pinnules. A frond is actually the entire sum of the parts that start at the base of the stipe all the way up to the tip of the blade.

It completely leaves out concepts like the blade, rachis, costa, costule, etc.

Thoughts?

I don't have time to work on it right now. I'll check back over the weekend and work on it when I have more time (if no one else gets to it before me).

++Arx Fortis (talk) 05:19, 14 April 2011 (UTC)

Actually, by definition a rhizome is a stem, just one that's horizontal and often underground. I don't see how you interpreted the information about the leaf to refer only to the pinna/pinnules. You are correct that the structure section does not describe every possible term associated with leaves, but it's not intended to. That information is better treated on the frond page than here; you might add more information there. This article is about the entire group of all ferns and about all aspects of their biology (fossils, classification, reproduction, chemistry, cultural significance, etc.), and too much detail about fronds here would probably unbalance the article. --EncycloPetey (talk) 05:31, 14 April 2011 (UTC)

Mutable terminology

A recent paper (Rai and Graham, 2010) has disputed the placement of Psilotopsida as sister to the other 3 classes of Monilophytes. This paper can be found at [2]. They regard the issue as essentially unresolved, but they find Equisetopsida to be weakly supported as sister to the other 3 classes. Does the phylogenetic tree in the Wikipedia article "Fern" amount to taking sides on this issue?

The second issue that i would like to raise is 'What will happen to the nomenclature when this issue is finally resolved?'. If Equisetopsida is indeed the most basal, then the meaning of "fern" might shift back toward its traditional usage, which excluded Equisetum. This is likely to cause a lot of confusion. 76.88.133.43 (talk) 04:08, 28 November 2011 (UTC)

Their weak support for the clade means they haven't added solid new findings. The placement of Equisetum was described as "Subject to further study" in the Pryer paper of 2004. The article is thus not taking sides, but showing one of the published possibilities. Authors will do this, because reducing a tree to a polytomy invites interpretations that were not present in the original analysis. --EncycloPetey (talk) 04:57, 28 November 2011 (UTC)

The uncertainty in the phylogeny is very clearly described in the paragraphs above the tree which is presented in the article, so the article as a whole can't be accused of not adopting a NPOV. The case for presenting the Smith tree is that it's not only a possible phylogeny but also a published classification. However, the text below the tree could have been read as perhaps a little definite. I've added a sentence based on the 2010 paper which I think corrects this possible impression. Peter coxhead (talk) 12:59, 28 November 2011 (UTC)

Palm trees

Someone who knows the subject please add a comment on the article as to whether Ferns are related to Palm trees as they look similar. Lot of people think it is the same species, but on TV I heard they are not. -.@Photnart. (talk) 00:44, 5 October 2012 (UTC).

Thank you. I have added a note at the end of the article text, with links to the flowering plant families involved. Chiswick Chap (talk) 06:56, 5 October 2012 (UTC)

Outdated classification

In the current classification of plants, there is no such taxon as "Pteridophyta". This is a paraphyletic assemblage of two separate evolutionary lineages, the true ferns (which includes Psilotaceae and Equisetaceae) and lycophytes (Lycopodiaceae, Selaginellaceae and Isoëtaceae). This page and all other relevant pages need to be edited to correspond to the current classification. I think the easiest way to proceed is to change the classification to that adopted in the Tree of Life web project. As a first measure, I am redirecting the Pteridophyta page to the Pteridophyte page, which explains the situation, and will aim to gradually update the rest. Cricetus (talk) 08:36, 12 June 2013 (UTC)

Classification of "ferns" is a tricky issue.

• The Tree of Life web project is not a reliable source, so in making changes, you need to refer to one that is. It may be "easier" to change to its classification, but this would not be consistent with WP:NPOV if there are other competing classifications in reliable sources (which I think there are).
• The monophyletic clades are pretty well established in reliable sources. However, the names are another matter. Smith et al. (2006), which is a reliable source (albeit not the best as it's a journal article not a secondary source) explicitly doesn't give a name to what you call "true ferns" above. Some of the same authors as in Smith et al. (2006) use Polypodiopsida in the ToL web page, but this is also used by other authors for just leptosporangiate ferns.

Personally I think the best approach at present is as to follow the same approach as for many of the higher ranks of angiosperms: use unranked clade names in taxoboxes and as article titles, and then note in those articles the range of formal taxon names currently in use. However, this probably needs more discussion, e.g. at WT:PLANTS. Peter coxhead (talk) 06:08, 14 June 2013 (UTC)

Yes, fern classification is tricky, that's why I did not start to make any major changes without opening the discussion first. What I called "true ferns" is what Smith et al. (2006) call either just "ferns" or "monilophytes". It is unfortunate that they did not provide an official taxon name for this group at any rank. In any case, using the term "Pteridophyta" for this group is very confusing, because Pteridophyta is generally thought to include also lycophytes. Has some RS provided a new circumscription of Pteridophyta that excludes lycophytes? If not, then the current use of Pteridophyta in these pages may also be original research. The Chapman reference that is now cited when Pteridophyta is mentioned for the first time in the text did not provide this circumscription; in fact, that publication does not use the term Pteridophyta at all. Is it possible to replace "Pteridophyta" with the unofficial "monilophyte" in all taxoboxes and other places where the intention is to talk about ferns and horsetails to the exclusion of lycophytes? Cricetus (talk) 09:04, 14 June 2013 (UTC)

The term "pteridophyte" is used by RSs to exclude lycophytes, e.g. in Appendix 1 here. But recent sources all seem to have abandoned formal ranks at this level, so I can't find a use of "Pteridophyta" as a formal name that excludes lycophytes, which is not to say that there isn't one!

However the term "monilophyte" is also used by RSs for the same clade, e.g. here.

There's a good case for preferring "monilophyte", even though it's less familiar, because "pteridophyte" is ambiguous between the old and new uses. However, this is OR. What there doesn't seem to be is a source with the authority of the APG which we could legitimately use to choose one name over the other. Yet, at least for article titles, there is a need to choose. Um... I'm going to raise this at WT:PLANTS, though I'm not sure that there are many there interested in ferns at present. I think we should wait to see if there is any response first, but then I agree entirely that this needs fixing, one way or the other. Peter coxhead (talk) 11:43, 14 June 2013 (UTC)

I'm not sure I see how using "monilophytes" would be OR; as long as the name is not assigned a taxonomic rank, its use is entirely consistent with Smith et al. (2006), who use it e.g. in their fig 1. Since the taxobox takes all the names of the extant classes from Smith et al's fig. 2, it would be logical to use the name they chose also for the next higher clade. If some other name is chosen instead, this should probably be justified by RS. Even if the inofficial term "Pteridophyte" has been used to refer to monilophytes in RS, using the taxon name "Pteridophyta" for that group is a different issue and needs its own justification from RS. Cricetus (talk) 13:41, 14 June 2013 (UTC)

Using "monilophytes" as a name isn't OR; using it as the name in a taxobox is different, since we would be choosing one alternative over another without any source comparable to the APG for there being a consensus to do this. However, in taxoboxes we have to make a choice, so the OR element is probably unavoidable. I would like to get more input into this discussion so I have raised the issue at Wikipedia talk:WikiProject Plants#Classification/nomenclature for ferns. Let's see if we get any helpful responses. If not, then I personally agree with you that "(unranked) monilophytes" is the best choice for the taxobox. Peter coxhead (talk) 13:49, 14 June 2013 (UTC)

I've reverted some recent (20 June) edits that redefined "pteridophyte" to exclude lycophytes and denounced the use of "monilophytes" as illegitimate (which appeared to be OR). I would note, first, that the use of unofficial terms like "pteridophyte" and "monilophyte" need not necessarily correspond to taxonomically validated names (i.e., we can talk about monilophytes even if "monilophyta" hasn't been validly published), and second, that the older use of pteridophytes is still probably dominant. For instance, Robbin Moran uses it in that sense in his "A Natural History of Ferns" (2004), a popular science work. I have accordingly updated the lead to reflect the uncertainty as to the term's circumscription. Choess (talk) 00:50, 12 July 2013 (UTC)

Also whether or not Monilophyta has been validly published according to the ICN, it is in use in reliable sources. The difficulty we have is that there appears to be no consensus terminology for ferns, yet we really need a single "navigational" classification for the taxoboxes. Peter coxhead (talk) 06:09, 13 July 2013 (UTC)

Comment

The fern pictured in the sistematics box is NOT Athyrium filix-femina. Jan Wesenberg, editor of Blyttia, Journal of the Norwegian Botanical Society —Preceding unsigned comment added by 79.161.198.9 (talk) 19:09, 1 May 2011 (UTC)

Actually this article doesn't say that it is, although other articles do. I agree that it certainly isn't the typical wild form of A. filix-femina: the pinnules are too small and the wrong shape (compare with, say, File:Athyrium filix-femina saint-michel 02 27052007 2.jpg). The only complication is that a wide range of selected abnormal forms of this and other ferns are grown in gardens, so it's possible that this is one of them. Peter coxhead (talk) 09:28, 6 December 2013 (UTC)