Talk:Tardigrade

Rearranging

I have added some sections and rearranged the paragraphs to make it a bit more logical (hopefully ;) GregRobson 23:48, 26 Dec 2004 (UTC)

Tardigrade sketch or image

A sketch or an image of how the tardigrades actually look like would improve this article a lot. Preferably a sketch, as it is often hard to make out the details on images on such tiny creatures. Jens Nielsen 22:55, 14 January 2006 (UTC)

You can google search an image of the Tardigrade and obtain a microscopic image of the creature, however i am not familiar with the proper process for uploading images and what not, so if any are aware of it please help

f1r3r41n 18:02, 1 February 2006 (UTC)

There is a cool one here http://tardigrade.acnatsci.org/tardigrades/pic311.png Suppafly 21:04, 14 March 2006 (UTC)

Copyrighted. Pavel Vozenilek 01:17, 15 March 2006 (UTC)

I have several images i'm willing to upload, they're from my BSc dissertaion, some are hand-drawn specifically detailing the general anatomy and CNS of the tardigraede. I will investigate the uploading process. 87.114.11.142 18:15, September 5, 2006 (UTC)

-272.8 degrees?

I have been unable to find anything on the 'net saying that tardigrades can survive -272.8 degrees Celsius. I have been able to find the following site: http://serc.carleton.edu/microbelife/topics/tardigrade/index.html, which says that they can survive -200 degrees Celsius, which sounds much more reasonable considering that "the Boomerang Nebula, with a temperature of -272.15 Celsius ; 1K, is the coldest place known outside a laboratory." (Absolute zero) Could someone change this? I've found a site: http://www.earthlife.net/inverts/tardigrada.html --Quadraxis 18:48, 6 January 2007 (UTC)

the water bear as a polar bear

I took a second year university circumpolar history class where the water bear was mentioned, definately not as a tiny creature. I remember the range to be as far south as Cape Cod. The waterbear was hunted to extinction since it competed for the blubber on seals and walruses. Also,the water bear was fearsome to whalers and settlers. The water bear was most probably the polar bear. Can anyone confirm this to be true? H. Lorne 01:33, 13 March 2007 (UTC)

Doubtful. Doo-dle-doo 21:39, 26 September 2007 (UTC)

Ya they were probably thinking of polar bear because the scientific name of polar bears is Ursus Maritimus, which means "sea bear" or "water bear" —Preceding unsigned comment added by 131.104.226.85 (talk) 04:07, 12 December 2007 (UTC)

No evidence for 100-year survival of tardigrades!

It is amazing how difficult it seems to be to give up old views. I find the story about 120-year survival of dry tardigrades repeated again and again, despite the fact that there is no evidence whatsoever that a tardigrade can revive successfully for such a long time. The paper that I wrote together with R. Bertolani in 2001 (cited in this page) had the specific aim of killing this myth, but nobody seems to be willing to accept the fact that a tiny movement of a leg is not equivalent to successful recovery of the animal. I would appreciate if the text after "Dehydration" could be replaced by the correct information that tardigrades have been shown to survive nearly one decade in a dry state, with reference to Guidetti, R. & Jönsson, K.I. 2002. Long-term anhydrobiotic survival in semi-terrestrial micrometazoans. J. Zool. 257: 181-187.

There is also a reference to "recent experiments" on chemobiosis by Cai and Zabder, without any reference to a publication. I think this is not acceptable, so should be deleted. In addition, someone has refered to our paper (Jönsson & Bertolani 2001) in this context, which is completely incorrect.

I hope somebody can change the text to make it more in line with current knowledge.

K. Ingemar Jönsson 04:22, May 25, 2007 (UTC)

I saw a show that says the longest living water bears, without water, was 127 years. 192.28.2.6 13:24, September 13, 2007 (UTC)

I saw a show where they autopsied an alien in real life. Lots of shows publish common misconceptions. Peer reviewed journals are what is needed here. --69.178.7.34 (talk) 14:34, 10 March 2008 (UTC)

From Manga Science Volume VI by Yoshitoh Asari, ISBN-05-202039-1 published in 6 March, 1998, a tardigrade survived over 120 years from a dried state and lived for 2~3 minutes before it actually died. The info was supplied to the book by a professor from 東京女子医科大学 named 宇津水和夫. If a specific paper could quote this to be wrong, by the five pillars of wikipedia, namely the WP:NPOV, this info should still be in the article, but immediate followed by sources with evidence stating it is in fact not considered survival. The sentence should be something like: "Although the tardigrade was said to have survived over 120 years after being in a dried state and lived for 2~3 minutes after being given water, and died afterwards,[ref 1] some further research doubt its accuracy since it is only a small movement in the leg.[ref 2]" Wikipedia should present all views, not a specific one. Especially when it is controversal. MythSearcher^talk 15:36, 10 March 2008 (UTC)

If this is a common misconception, then it should be mentioned as such, not deleted. — Omegatron 00:34, 29 March 2008 (UTC)

Agreed! But the article is still listed as "twelve decades" under dehydration, no mention of the "controversy". Tweil (talk) 13:27, 9 May 2010 (UTC)

Questions

Normal life span? What do they feed on? —Preceding unsigned comment added by 86.163.165.101 (talk) 21:45, 9 September 2008 (UTC)

Answer: tardigrades are suctorial feeders. They mainly eat plants and small animals though some are gut parasites of molluscs and echinoderms. Hope this helps. —Preceding unsigned comment added by Geologyrocks101 (talk • contribs) 13:51, 7 January 2009 (UTC)

Space. The Final Tardigrade Frontier

These little water bears can survive direct exposure to space environment with no protection.

• http://www.dailymail.co.uk/sciencetech/article-1054351/Tiny-water-bears-creatures-survive-space.html —Preceding unsigned comment added by Root Beers (talk • contribs) 13:13, 11 September 2008 (UTC)

Extremophile

From a very technical perspective, the Tardigrade enters cryptobiosis in hostile environments, which is very different from thriving in them. Does this not exempt them from extremophile status? —Preceding unsigned comment added by 76.181.155.184 (talk) 15:49, 12 November 2008 (UTC)

     I'm not a biologist, but from what I have read about various types of extremophiles (which fascinate me because of what they may indicate about life beyond our planet, and also because water bears are just plain amazing), despite what "-phile" (=to love; therefore, in this context, to prefer, and by extension to thrive in) might imply from a strictly etymological point of view, another way that these creatures are talked about is in terms of their ability to simply survive in certain extreme conditions. Thus, deinococcus radiodurans is able to survive tremendous amounts of radiation.    

      Does this mean d. radiodurans thrives in such contexts? No, according to what appears to be a well-referenced Wikipedia article on this bacterium, it (a) has decreasing survival rates as the amount of radiation gets above a certain level and (b) that this bacterium has mechanisms akin to, but not the same as, the tardigrade for enduring high levels of radiation. So, I think this situation is similar to that of the tardigrade in that both do not thrive as the degree of the extreme condition increases beyond a certain level. Rather, they have rather astounding survivability under certain extreme conditions. On the other hand, there seem to be extremophiles which do, in fact, thrive under what we would consider extreme conditions only. You make an interesting point, but it seems that the distinction between surviving and thriving is not made in the concept "extremophile". Is there a biologist who can tell me if I'm on target here? Eenwikilekter (talk) 06:06, 31 October 2010 (UTC)

Tardigrades are not segmented

In the introductory section to the article it states that tardigrades are segmented animals, which is wrong, to the best of my knowledge. They are monomeric with four pairs of unjointed chelate legs.

Tardigrades in popular culture?

Mal Webb (Mal Webb, http://malwebb.com), an Australian performer, has a song on his "Trainer Wheels" CD about waterbears, listing (most of) the various extreme environments they can survive. Is this worth noting on the page? --PaulWay (talk) 23:57, 24 September 2009 (UTC)

food of water bear

What do they eat? How long can they live? —Preceding unsigned comment added by 116.15.108.167 (talk) 17:29, 8 November 2009 (UTC)

Chemobiosis

I'm currently wondering about the section on the resistance against environmental toxins. It states that tardigrades can undergo "chemobiosis", which is told to be a form of cryptobiosis. The thing is, you can't find anything at all about chemobiosis in the web except quotations of this article and the article about Cryptobiosis. So I've asked the guy who added the section about chemobiosis in this article and he told me, he got the information from here. So, does chemobiosis really exist???

Besides, the evidence about chemobiosis does, like already told above by K. Ingemar Jönsson, not belong at all. I assume this to be a mistake, because the two references were already there before the line about chemobiosis was added (in January 2006 by user Kimmylee).
--Johannes Rieke 16:21, 14. April 2010 (UTC)

Genome

The section states "is being sequenced" without mentioning a date. It is quite common in Wikipedialand for the present tense to be used without any indication of when. I wonder what the policy is with this. Obviously it cannot remain true indefinitely, but does the usage imply that the writer will monitor progress and update the article when the sequencing has been completed? Dawright12 (talk) 10:10, 11 July 2010 (UTC)

This practice is generally discouraged as is the use of words such as "recently". If it is to be included it should be qualified with "as of XXXX" or something to that effect. mgiganteus1 (talk) 11:36, 11 July 2010 (UTC)

As Mgiganteus1 says, writing in that way is discouraged for precisely that reason. Relying on somebody to update it when required is not a reliable approach. It is better to make a statement that will remain true, e.g. "A sequencing project was started in 200x". In this case, the reference link provided says that the work is still ongoing but I am not sure how we can tell that this is kept up-to-date. --DanielRigal (talk) 11:44, 11 July 2010 (UTC)