This article is written in American English, which has its own spelling conventions (color, defense, traveled) and some terms that are used in it may be different or absent from other varieties of English. According to the relevant style guide, this should not be changed without broad consensus.
Earthworm is within the scope of WikiProject Soil, which collaborates on Soil and related articles on Wikipedia. If you would like to participate, you can choose to edit this article, or visit the project page for more information.SoilWikipedia:WikiProject SoilTemplate:WikiProject SoilSoil articles
Earthworm is within the scope of WikiProject Animals, an attempt to better organize information in articles related to animals and zoology. For more information, visit the project page.AnimalsWikipedia:WikiProject AnimalsTemplate:WikiProject Animalsanimal articles
Why does the See Also section of this article link to the French Wikipedia article for La Station d'écologie de Lamto? So far as I can tell, that article does not have anything to do with earthworms? TheMrP (talk) 23:05, 5 February 2018 (UTC)[reply]
Earthworms are amazing creatures that play a vital role in soil ecosystems. They feed on organic matter in the soil and excrete it as castings, which are rich in nutrients and beneficial microorganisms. Earthworm excretion helps improve the soil structure, fertility, and water-holding capacity. It also reduces soil compaction and erosion, and enhances plant growth and health. — Preceding unsigned comment added by 2604:3D08:BD80:CF00:495:469A:4DF:2A77 (talk) 21:37, 2 November 2023 (UTC)[reply]
Could someone include the protein content/nutritional value of the common earthworm? They're delicious creatures, and very pleasant to eat for those with poor digestion.
Keep in mind the "Threats to Earthworms" Section. While they might be pretty yummy (Not that I would know) it's probably pretty dangerous to try to eat them because of all the chemicals in the ground that they consume.
[it's probably pretty dangerous to try to eat them because of all the chemicals in the ground that they consume] you could just cook it —Preceding unsigned comment added by 216.162.81.161 (talk) 16:48, 4 May 2009 (UTC)[reply]
I would like to see nutritional information for earthworms. Percent protein, fat, etc, but particularly the amounts of vitamins and minerals. —Preceding unsigned comment added by 24.56.247.187 (talk) 10:17, 6 May 2010 (UTC)[reply]
"Various species of earthworms are used in vermiculture, the practice of feeding organic waste to earthworms to decompose (digest) it, a form of composting by the use of worms. These are usually ''Eisenia Fetida'' or the Brandling worm, also known as the Tiger worm or Red Wriggler."
Eisenia Fetida doesn't actually live freely in the soil but in compost so arn't really earthwormsm, but I'll leave the article as it is for now...quercus robur
Oligochaeta (which is either a class or subclass depending on the author)
Except that the taxobox lists oligochaeta as an order. I'm not knowledgable enough to correct this myself, but consistency within the oage would be nice. Rho 23:02, 16 Sep 2004 (UTC)
Thanks for pointing that out. The order level taxon should have been Haplotaxida. This got mislabeled in one of the changes in taxobox format. WormRunner | Talk 05:20, 17 Sep 2004 (UTC)
I have heard that earthworms have powerful regenerative abilities, being able to regrow if cut in half. I have even heard that if cut in half, an earthworm can regenerate into two new individuals. Is this true? Please add info to the article. SpectrumDT22:26, 4 November 2005 (UTC)[reply]
I have heard that it must be cut precisely in half as to leave all the main organs of each half intact. But I can't remember where I heard that.
Earthworms do not regrow into two new individuals. Some earthworms can regenerate their posterior segments, but the back half dies. If the cut is in the anterior third (or so), the whole worm will probably die. There are some aquatic Oligochaeta (not earthworms) which can regenerate whole new individuals from both cut sections. -- WormRunner | Talk06:55, 24 November 2005 (UTC)[reply]
G.E. Gates spent several years determining the regenerative abilities of earthworms. Because the incision levels from anterior or posterior overlap in several species then, in theory at least, it is possible to get two worms from one "individual". Head regererates are farily common in some Lumbricidae, and I have seen them in Pontoscolex corethrurus (Glossoscolecidae). One of the most adept regenerators is Perionyx excavatus (Megascolecidae). Hope this helps the discussion. Rob B.
This is great that there is challenging opinion here. Why is the research by Gates not more widely publicised? Has it had peer criticism? I notice he starved the worms for the experiment. One would expect that this would impair their growth, so perhaps in normal living conditions, with access to food and normal soil moisture, they might regenerate even better? I'm not a scientist really but I am researching earthworm conservation and it would be useful to know the truth, more up to date research if helpful as there's such conflicting information online.
So... would it be possible to really review all the research and even explain why many sites say cutting is not good for them? I expect it uses up energy unnecessarily. Natalie W. — Preceding unsigned comment added by 2.121.204.48 (talk) 12:17, 10 December 2012 (UTC)[reply]
"Lumbricus terrestris Linnaeus, 1758 replacing anterior segments from as far back as 13/14 and 16/17 but tail regeneration was never found." - i am not sure i understand this correctly, because i do not know english well. replacing means regrowing? so if head us cut off, it can regrow ? ie small part of head site is cut and thrown off , and the left long tail regrows new head ? (whole length is near 100). what does mean "13/14 and 16/17" ? line between section 13 and 14 and line between sections 16 and 17 ??? "tail regeneration" is regrowing new tail ? i understand this as i written. but russian text at ru:Регенерация and reply in this topic says vise versa --Qdinar (talk) 17:02, 18 June 2013 (UTC)[reply]
The article refers to Gates (1972) without identifying the publication further. Is this
Gates GE. 1972. "Burmese earthworms: an introduction to the systematics and biology of Megadrile oligochaetes with special reference to Southeast Asia". Trans. Amer. Phil. Soc. 62: 1-326.
Until fairly recently, earthworms have been considered good for North American soil. With the realization that they endanger forests in the United States that have adapted to grow without them, I think we probably are overplaying their role as decomposers "that almost all plants and animals rely on". This makes them seem as important as the fungi, and they are certainly not.
Some earthworms are foreign invaders in North American forests, mostly Lumbricidae. Some North American forests and prairies developed without earthworms and have been changed by these invaders, but other forests already had their own (native) earthworm species (mostly Megascolecidae), especially in the moister areas of the Southeastern and Western US. -- WormRunner | Talk07:00, 24 November 2005 (UTC)[reply]
can anyone provide knowledge of whether or not it was actually the NA glaciers that depleted wide areas of earthworms, and they are not therefor "invasives", they are in reality re-populators. —Preceding unsigned comment added by 206.51.193.200 (talk) 18:51, 2 September 2010 (UTC)[reply]
When did earthworms evolve? Or more precise; when did they leave water and started to live in the earth in terrestrial enviroments? Why did they do it and what adaptations did they go through? Who were their ancestors? In what ways have the worms and the plants evolved together in symbiosis? And why is it so hard to find information about these things?
I'm guessing that it's because they don't have bones and don't work their way into tar pits. There are other forms of fossilization, but basically that's why I would suspect there isn't tons of information about it. But there are probably theories at the least. I wonder. Lotusduck19:57, 5 January 2006 (UTC)[reply]
Amynthas hupeiensis will coil but remain motionless when disturbed, unlike most other pheretimoids, and it emits quite a strong odour. So yes, perhaps it is playing possum.
Do earthworms mate in mating balls like garter snakes? I recently observed a small mass of earthworms forming something quite like a garter snake mating ball. The references I found online in a quick bit of googling all seemed to describe earthworms mating in pairs.
The rainstorm section should be rewritten. The fourth theory presented in the section, about carbonic acid, is completely false. Although the ground may contain a good amount of carbon dioxide, carbonic acid is NEVER present in sufficient quantities to affect the pH in any significant way. —Preceding unsigned comment added by 69.248.83.175 (talk) 15:23, 25 November 2007 (UTC)[reply]
Do earthworms feel pain? (header was "dissection....")
"The classroom dissection of the earthworm and other animals has become controversial in recent years. One response to this has been the development of online "virtual dissections" But.....they're worms. I mean. They don't even have a brain. How could they feel pain? Besides, in Biology 2, I disected a dead one which was preserved in formaldehyde (or some substitute thereof).
They do have a brain, albeit a simple one, but more important is that they have a nervous system. When poked, they respond in a way that makes it very difficult to believe they do not feel pain in some way. Very much like you would, for example. Certainly a worm that is already dead will not feel pain, but I cannot imagine being dropped in formaldehyde is a pleasant experience either. I do research on earthworms, and I believe research and education are important, but let us not pretend the process is painless. -- WormRunner22:53, 16 August 2006 (UTC)[reply]
Worms have such small brains that rationalized thought is not possible. Their nervous system is very symplistic with no central nerves, like in humans, so I doubt if pain would be possibel as well.
Pain is not a function of "rationalized thought". Grief and sadness may be related to rational functions, but I'd imagine that pain has been around since the early days of nervous systems. --72.150.43.254 (talk) 23:55, 13 January 2008 (UTC)[reply]
In 2005, media reported about research that said worms do not feel pain[1]. But there's probably more to it.[2] I don't want to do any original research, but there are probably so reliable sources out there about whether (earth)worms feel pain that could be used to add something about it to the article. --82.170.113.123 (talk) 10:25, 16 May 2012 (UTC)[reply]
I will do a section on the nervous system, including anything I can find in reliable sources regarding pain. Unfortunately the ABC News story you mentioned probably does not pass Wikipedia reliable source standards for medical information, and so I am disinclined to use it, but I will look for proper peer-reviewed scientific journals on the subject. Zad6813:26, 16 May 2012 (UTC)[reply]
The crop...Isn't that for storage? I read in this article that it is for grinding, but have read elsewhere that the "gizzard" performs this function in earthworms. I think (and I'm probably wrong) that the crop is a portion of the digestive just before the gizzard, which stores the dead organic matter it eats prior to grinding. Any ideas? Is it different in oligocheates? —Preceding unsigned comment added by Aydan Wessels (talk • contribs)
I would find it very interesting to know something about who are the closest relatives to the earthworms, when they first left the water and crawled onto land, and how much impact they have had on the flora and faune of earth since they first evolved and how important they are today etc. If this could be added somewhere in the article, it would imprive greatly. 217.68.114.11615:53, 29 November 2006 (UTC)[reply]
I don't know much (anything) about Earthworms, but I found this article to be very informative and well written. I'd like to offer a friendly critique: the article could use a great deal more citations throughout.
Nice work to everyone that's contributed so far! I've gone ahead and given it a B-class rating, I hope you're all in agreement. A great example of a developing wikipedia article. I've also added this article to my watchlist and will keep a sharp eye out for vandalism (it's about all I can help out with here). --Nemilar 04:39, 13 March 2007 (UTC)
PLEASE help to reduce the vandalism - almost every other edit is mischievous. —Preceding unsigned comment added by 123.198.14.36 (talk) 17:26, 1 November 2007 (UTC)[reply]
They eat dead and decaying plant material -- but there is an opinion that what they really digest is the soil microbiota. I'd prefer it if someone with more direct knowledge than me were to fill this bit in. jake b20:33, 8 May 2007 (UTC)[reply]
Worms move primarily soil through their digestive systems (it's how the ground is refertilized). However, I have little knowledge on how worms recieve energy from eating dirt.
There is a bit on accumulation up the foodchain (in 'threats' section). COuple of comments: 1. Bioconcentration factors (BCFs) of >20 are very common. I don't know where this figure came from. 2. OK, the principle of bioaccumulation is well-established, but are there any real examples of wildlife mortality (or any health problems at all?) from eating toxic worms? I'm not aware of any in the scientific literature -- if this isn't backed up by citing something reliable, I think this should be deleted. jake b20:31, 8 May 2007 (UTC)[reply]
OK, no response so far, so I have deleted this misleading section. (If someone wants to add a more reliable bit on bioaccumulation elsewhere, then great.)155.198.148.17319:21, 26 June 2007 (UTC)[reply]
There are a couple of references to earthworms "acting as pistons". Is there any scientific evidence to back this up? (The quotation cited does not appear to be based on any actual data.) Seems much more likely to me that the principal benefits on soil aeration are going to be through changing soil structure, rather than this piston idea. (Which presumably would only have any validity at all for anecic worms anyway?) Not to mention that the whole concept is repeated in successive sections anyway. Worldoffish (talk) 22:28, 18 March 2009 (UTC)[reply]
I agree that this section needs some work. Specifically, under the "chemical" subheading, I read that "Investigations in the US show that fresh earthworm casts are 5 times richer in available nitrogen, 7 times richer in available phosphates and 11 times richer in available potash than the surrounding upper 6 inches (150 mm) of soil.", with no reference whatsoever. I read similar figures in Steve Solomon's "Organic Gardener's Composting", which I will investigate to see what source he cites.
However, the references for this article as a whole needs some serious improvement.
I would be interested to know whether earthworm casts are so concentrated because of some special habit or property of the earthworm, or whether it is simply due to the universal nature of heterotrophs to concentrate nutrients in their poop. Any ideas? Noclock (talk) 23:47, 15 April 2009 (UTC)[reply]
can anyone verify or cite reliable information on the amount of worm castings a worm produces in a day, particularly re the statement often heard that they produce their weight in castings each day. —Preceding unsigned comment added by 206.51.193.200 (talk) 18:53, 2 September 2010 (UTC)[reply]
I don't know why someone has changed this to four categories - there are three standard accepted ecophysiological categories not four! Earthworms pretty much only live in what we would commonly call 'topsoil' layers, which are not to be confused with actual soil horizons. Epige worms are litter/compost worms. I have checked the reference given for this comment (no. 4), and although it's not the best (that would be the original reference from Bouche -- this one isn't a proper peer-reviewed article), it does quite correctly give the three classes only, so I have left it in there. 155.198.148.173 (talk) 19:59, 7 July 2008 (UTC)[reply]
Sadly, this whole article is losing consistency - it's written very patchily, with different levels of fact and speculation in different places. There are all kinds of statements and comments just shoved in at random, i.e. in inappropriate sections. I think it would be ideal if someone would do a complete rewrite (maybe I'll have a go in the future, but don't have time now). I've also added Edwards + Bohlen's "Biology and Ecology of Earthworms" under further reading, as I have always considered this the most comprehensive and authoritative text for the general reader. (I see there's a 4th edition coming out but haven't got a copy yet.) Is there a way to highlight this text in particular, as a way of getting reliable information on earthworms? (I don't count myself as an expert earthworm biologist, for sure.) Worldoffish (talk) 18:05, 16 March 2009 (UTC)[reply]
Just had another look - maybe I was unfair to many persons' efforts before . The first half of the article (up to and including 'regeneration' is well written and informative - it's the remainder which is still could do with severe editing. Worldoffish (talk) 22:20, 18 March 2009 (UTC)[reply]
earthworms as well as leeches and many segmented marine worms are annelids they belong to phylum annelids
they name phylum comes from latin term annulus which main ring annelids have bodies that are divided into
segmentation they have more complex bodies and well developed organ system than any other worms CEATED BY; EDDMARC —Preceding unsigned comment added by 119.95.151.88 (talk) 12:03, 17 March 2009 (UTC)[reply]
Edwards, C.A. (1996). "Diversity and geographical distribution". Biology and ecology of earthworms. Springer. pp. 40–41. ISBN0412561603. Retrieved 2009-04-12. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help) Pp. 40-141 say that: earthworm species are either very localized or near-global in distribution; the near-global ones have been spread accidentally by humans; the localized ones live in the northern hemisphere, between the deserts and seas to the south and the southern limit of the Quaternaryglaciations, which suggests that more northerly populations were wiped out by the ice and the southerly populations have been very slow to re-colonize the devastated areas. --Philcha (talk) 21:07, 12 April 2009 (UTC)[reply]
The entire Behavior subsection "Rainstorms," despite being poorly written, completely trivial, and totally lacking in attribution or citation, is likely adapted completely from this website:
As it stands, it should be removed until it becomes coherent, informative (which it is not), and attributable.
Examining the page history, this section developed over a number of edits from different editors. See, for example, this edit. So it's far more likely that miscfaq.com, which does not provide its sources, got information from Wikipedia. At the moment I think the article is more informative retaining this section than it would be if the section were removed; the maintenance tags rightly draw attention to the need to cleanup and verify. Feel free to help find sources. Adrian J. Hunter(talk•contribs)15:11, 24 September 2009 (UTC)[reply]
These single celled earthworms eat in a unique way: their mouth cavity connects directly into the digestive tract without any intermediate processes. Most earthworms are decomposers feeding on undecayed leaf and other plant matter, others are more geophagous.
Single celled earthworms? I don't think such a thing exists! Does the writer really mean "singled celled" or do they mean "single cavity" or something odd that I'm not thinking of? This should either be explained or removed! —Preceding unsigned comment added by John Elson (talk • contribs) 15:57, 30 September 2009 (UTC)[reply]
"...worms may be using the moist conditions on the surface to travel more quickly than they can underground, thus colonizing new areas more quickly...".
How could a worm care to colonize if it is living well off where it is at?
The urge to explore and wander around. Consider yourself, you don't just stay where there is food to eat do you? A 1 hour crawl is not such a huge departure from home anyway. Natural selection will have picked the ancestors of those worms that trieed new places to live, rather than staying put in one spot. Graeme Bartlett (talk) 10:53, 12 May 2010 (UTC)[reply]
I think the article is too long and includes items of pretty low relevance as it is. However if you want to start a separate article on earthworm bioluminescence, go for it. Worldoffish (talk) 17:12, 28 October 2010 (UTC)[reply]
Earthworms only exist in Australia, North America, and UK?
This article does not mention where Earthworms live around the world. In know the exist in Asia. Where else do they live and what kinds of worms exist at different places? —Preceding unsigned comment added by 183.89.179.62 (talk) 11:36, 5 April 2011 (UTC)[reply]
"From a total of around 6,000 species, only about 120 species are widely distributed around the world. These are the peregrine or cosmopolitan earthworms"
Cosmpolitan: growing in many parts of the world; widely distributed
"However, this behavior is limited to only a few species and L. terrestris is rarely, if ever, one of those found stranded on impermeable surfaces, this hypothesis does not seem likely to be true." because there is no citation. Yyes I am aware that the section as a whole is screaming for them, but this particular sentence seemed a little too subjective. I mean "this hypothesis does not seem likely to be true."? Come on now, then I can say my hypothesis is that you are a neanderthal and it is absolutely, definitely, highly, most likely, to be true ;) — Preceding unsigned comment added by Hodeken (talk • contribs) 16:15, 19 October 2011 (UTC)[reply]
Proposed split of section, Earthworms as Invasive Species, to new article
I think this topic is notable enough and distinct enough to deserve its own article, along the lines of Gypsy moths in the United States. There is more information that could be added, and probably will be added as awareness grows among the public. The parent article is almost large enough that a split could be advisable based on size alone.--Brambleshire (talk) 15:21, 29 April 2012 (UTC)[reply]
I am removing this whole section from the article, because it's entirely unsourced personal speculation and original research. But I didn't want to lose it entirely so I'm putting it here. I'll go back later and see if I can find reliable source support for any of this, but I haven't seen it addressed yet in good scientific sources.
Earthworms can sometimes be found on the surface of the ground following heavy rain storms, as a storm may flood the soil with excessive water. However, if the surface where they find themselves is unexpectedly paved, rocky, or compacted (hardened), they may become stranded, potentially suffering injury or death from causes such as heat, exposure, dehydration, or predation. Note, there are some earthworm species that can survive for several days in water if it is sufficiently oxygenated.
Earthworms may also come to the surface during rain in order to mate, and therefore, an alternative hypothesis concerning "stranding" behavior is that as some species (notably Lumbricus terrestris) come to the surface to mate, they may become stranded.
Another hypothesis is that the worms may be using the moist conditions on the surface so they can breathe and to travel more quickly than they can underground, thus moving to and colonizing new areas more quickly. Since the relative humidity of the surface and air is higher during and after rain, they do not become dehydrated quite as rapidly. However, if true, this is a very risky behavior near dawn, in high summer, or in the daytime, since earthworms die quickly when exposed to direct sunlight with its high heat, light and strong UV content, and are more vulnerable to predators such as birds.
A further hypothesis is that, because there are many other organisms beside the earthworm in the ground as well, and these organisms all tend to increase respiration as water content of the soil increases, carbon dioxide gas may dissolve into the rainwater forming a higher than usual acid content carbonic acid in the soil area. As the soil becomes too acidic for the worms, they seek a more neutral environment on the surface.
"An earthworm is a segmented animal commonly found living in soil that is shaped like a tube (the gut) within a tube (the body)." - i've never seen soil shaped like a tube within a tube. 99.183.195.160 (talk) 16:18, 3 September 2012 (UTC)[reply]
I have a zoology text on my desk that declares the dorsal vessel to the the "true heart" and the aortic arches to be simply valves the regulate the flow of blood to the ventral vessel in a steady flow. Every illustration I find via google searches of images seems to label the aortic arches as the hearts. Which is it?Zedshort (talk) 22:31, 18 April 2013 (UTC)[reply]
I saw the edit about "true heart" and it was my understanding that the earthworm didn't have "a" true heart like mammals do. I had made a mental note to ask you about that. What is the title and author of the zoology text, I may have some better sourcing for you. (It was on my list to bring this article to GA, is that your plan? ) Zad6800:42, 19 April 2013 (UTC)[reply]
I read with a pen and find plenty I read in need of improvement in one form or another. I reworked the "Soil" article and am moving from there to subjects related to soil. This article needs a bit more. Here is my reference...Cleveland P. Hickman Jr., Larry S. Roberts, Frances M Hickman (1984, 7th ed.). Integrated Principles of Zoology. Times Mirror/Mosby College Publishing. p 45. ISBN0-8016-2173-9. It is a college level reference. Zedshort (talk) 14:54, 19 April 2013 (UTC)[reply]
We could use a better sketch of the anatomy. I searched WP for such a thing and found nothing compelling. I am not familiar with the process of adding images to the library. Zedshort (talk) 03:06, 22 April 2013 (UTC)[reply]
This edit request has been answered. Set the |answered= or |ans= parameter to no to reactivate your request.
"Several common earthworm species are mostly parthenogenetic, that is, with asexual reproduction resulting in clones."
The above statement, located under 1.6, Reproduction, should have a clearer definition or "parthenogenetic", or none at all. Currently the goal of the sentence appears to be to communicate that many common species of earthworm are capable of parthenogenesis and define the term, but is sloppy. The sentence may simply be "Several common earthworm species are mostly parthenogenetic." Alternatively, "that is, with asexual reproduction resulting in clones" could be revised to something like "that is, are capable of asexual reproduction yielding clones."
Under 3, Locomotion and importance to soil, there are a couple simple errors. "...as a result of the its movment through its lubricated tunnels" should be corrected to read "as a result of their movement through their lubricated tunnels."
Are there any estimates of the total number of earthworms in the world? Some sources say that there can be maybe 1,000,000 per acre of good soil. Some information about numbers would be good in the article. 86.160.221.91 (talk) 21:50, 17 February 2014 (UTC)[reply]
Feel free to add material to the article that is insighful. If you don't feel comfortable doing it yourself. Type it in here on the Talk Page and someone might pick it up and put it into the article. Zedshort (talk) 20:33, 27 January 2016 (UTC)[reply]
I'm interested in adding something along the lines of "The ability to break down organic materials and excrete concentrated nutrients makes the earthworm a useful candidate for soil restoration. In response to ecosystem disturbances, some mining sites utilize earthworms to prepare soil for the reintroduction of native flora." Do you (or others) feel this is appropriate for the benefits section? I may elaborate further if this seems like a good idea. Physiology-is-fun (talk) 20:40, 2 February 2016 (UTC)[reply]
References
^Boyer, Stephane (2010). "The potential of earthworms to restore ecosystem services after opencast mining - A review". BASIC AND APPLIED ECOLOGY. 11 (3): 196-203. doi:10.1016/j.baae.2009.12.005.
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What is the birthing process like with earthworms?
Eathworms is the article I have chosen. This article was pretty lengthy, but included basic information about this animal. The information stays pretty relevant to the topic. While reading I did notice some gaps and lack of citations at first, but the author and others were able to add information and the correct citations.One thing that bothered me was the layout of the page and how many topic changes there were. They may be able to group certain topics together such as Orgin and History with Evolution. As far as tone goes, this article is pretty scientific and so most information presented are facts.