Talk:Magnetoreception/Archive 1

Humans
I'd like to add this: "Humans can feel magnetic fields if one puts a magnet up to one's upper nose in an experiment." but I can't find any references, and I'm not sure of its validity. Would people be so kind as to try this experiment I devised and list results here? Thanks... (And no, I'm not some new-age sense-your-aura guy; I'm a scientist who knows that humans have magnetic materials in that area of the body.) 68.100.224.150 18:50, 21 July 2006 (UTC)Ninjagecko


 * This isn't the place. We have a policy against doing research yourself.  You'll have to find references. — Omegatron 20:04, 21 July 2006 (UTC)

Claims about magnetite in the human nose are unsupported
The statement "Humans have a similar magnetite deposit in the ethmoid bone of the nose, and there is some evidence this gives humans some magnetoception" is unsupported and might well be a urban legend. Let's examine the two references: Dragice (talk) 22:42, 2 November 2008 (UTC)
 * The online article Do humans have a compass in their nose? is vague and unreliable. It says "Some years ago [when?] scientists at CALTECH [who?] discovered that [...]". But there seems to be no publication from CALTECH on this topic (see this article).
 * The scientific article Evidence of a nonlinear human magnetic sense is misquoted. The terms nose, magnetite and ethmoid appear nowhere in the article. Therefore it should be removed from the list of references.

I reformulated the sentence; evidence for magnetite in the nose is here:. AxelBoldt (talk) 21:58, 13 February 2009 (UTC)

Great job! Dragice (talk) 23:08, 1 March 2009 (UTC)

Are you aware of Thorsten Ritz's and Klaus Schulten's work on magnetoception. They work with the Theoretical and Computational Biophysics Group of the University of Illinois, the NIH, and so. They propose a magnetosensory organ in birds that consists of a system of radical pairs that are orientationally ordered in the eye. Also, they propose that a photoreceptor is part of the radical-pair system and that its sensitivity is modulated through the magnetic field effects on the radical-pair system. If one assumes an anisotropic hyperfine coupling, one can calculate in a simple radical-pair model how the response of the photoreceptor is changed depending on the angle of the magnetic field lines with the radical-pair system. Assuming that the radical-pair/photoreceptor system is distributed equally over the whole eye, one can evaluate how vision of a bird is modulated. — Preceding unsigned comment added by Xapaxava (talk • contribs) 18:03, 21 June 2011 (UTC)

Possible addition to the section about mechanisms
This article correctly says that the physical mechanism for magnetoreception is unknown (yet) and lists two main hypotheses. It looks like finding a true mechanism is not behind the mountains. However, the problem remains unsolved for many decades, which is rather unusual for physical science. It seems to me that the article should clearly point to the fact that magnetoreception is a big physical problem. I think, something like the following fragment would be relevant to include after the 3rd paragraph of section “Proposed mechanisms.” :

Both the mechanisms meet serious difficulties in their physical justification, and both involve additional hypotheses to increase magnetic sensitivity to a level required by observable magnetoreception.* A suggested solution to this problem makes both the mechanisms to act simultaneously: a weak external magnetic field turns a magnetite nanoparticle that launches a radical-pair reaction.** It works because magnetic nanoparticles have their own magnetic fields that exceed the external geomagnetic one by a factor of 100-10000, in their vicinity.

{*} Binhi V.N. Magnetobiology: Underlying Physical Problems. Academic Press, San Diego, 2002.

{**} Binhi V.N. Do naturally occurring magnetic nanoparticles in the human body mediate increased risk of childhood leukaemia with EMF exposure? Int. J. Rad. Biol. 84(7):569-579, 2008.

-- — Preceding unsigned comment added by 188.123.230.154 (talk) 08:52, 20 October 2012 (UTC)

Jim Al Khalili mentioned magnetoception in this talk
In January 2013, Jim Al Khalili mentioned bacteria and birds that sense the magnetic field of the earth in his talk at the Royal Institution and discussed recent research into how they work http://www.youtube.com/watch?v=wwgQVZju1ZM It's certainly a fascinating area of biology. telewatho (talk) 11:49, 30 March 2013 (UTC)

Title and scope of this article
"The ability to respond to magnetic ﬁelds is ubiquitous among the ﬁve kingdoms of organisms" is a quote from here. If so, Magnetoception must be considerably expanded to represent this. However, I feel that this would make the article too lengthy and confusing. I propose to move this article to Magnetoception (animals). The sections on magnetoception in humans and bacteria could then be moved to other articles. This is particularly the case for magnetoception in humans for which the evidence is highly controversial.__DrChrissy (talk) 17:30, 13 June 2013 (UTC)


 * Mmm, but in that case we'd need a tree of articles:
 * Magnetoception (i.e. the parent article)
 * Magnetoception in animals
 * Magnetoception in bacteria
 * Magnetoception in humans
 * M...... etc.
 * the point being that we'd still have to have an article, this one, called Magnetoception. So it shouldn't be a move, but there could be sub-articles once enough material has been created. Also, the sub-articles would probably be best named without parentheses. Chiswick Chap (talk) 18:03, 13 June 2013 (UTC)
 * Fair enough - that would suggest expansion of the current article with sub-headings of "In animals", "In plants", etc and then subsequent moving to sub-articles when there is sufficient information. Is there a policy on naming articles with or without parentheses? I have heard various opinions.__DrChrissy (talk) 19:16, 13 June 2013 (UTC)

Larger mammals
I'm not sure if this 2008 study is worth mentioning in the article in the Mammals section. Magnetic alignment in grazing and resting cattle and deer. The abstract ends with: "This study reveals the magnetic alignment in large mammals based on statistically sufficient sample sizes. Our findings open horizons for the study of magnetoreception in general and are of potential significance for applied ethology (husbandry, animal welfare). They challenge neuroscientists and biophysics to explain the proximate mechanisms." --Spiffy sperry (talk) 18:09, 19 June 2013 (UTC)
 * Yes it is. I have included it in the article, along with a more convincing follow-up study.__DrChrissy (talk) 19:58, 19 June 2013 (UTC)

Update
Link. A new study from an RS. Others familiar with the article may wish to add it.--Canoe1967 (talk) 03:10, 21 August 2013 (UTC)

Bees
RE this edit. As far as I can tell Ferrari 2014 is the only paper to suggest that geomagnetism can disrupt navigation in bees and given that it has only been cited once by other scientists I'm concerned about the way it is used in the article at the moment. The Walker & Bitterman articles are much more sceptical and don't support the content at present. I've asked at WP:REX for a copy of this source which cites the Ferrari paper to help us determine WP:WEIGHT but as it stands I think this section should be removed and rewritten with secondary sources. SmartSE (talk) 20:39, 20 August 2015 (UTC)


 * . Please see the above and note that the source is available here. I've since realised that it's written by the editor of the journal that published the Ferrari paper so still isn't much help in determining weight. Nevertheless: "it is still far from clear what role this ability plays in normal bee navigation" is very different to the present "There is growing evidence that interference of the honeybee's geomagnetic sense can result in disruptions to their orientation". As primary pieces of research the papers (and particularly Ferrari) should be removed. SmartSE (talk) 11:11, 21 August 2015 (UTC)


 * I also notice that there are similar problems in the dog section. SmartSE (talk) 11:15, 21 August 2015 (UTC)


 * My apologies for missing it, that DrChrissy did not include the contested source when he edit warred the content back into the article; it was included the 1st time per SmartSe's dif above. I would have self-reverted b/c my rationale was not correct but DrChrissy already did. In any case, the current content is still supported only by primary sources; please base science-based content on reviews.  This is directly related to the discussion at Talk:Colony_collapse_disorder  Jytdog (talk) 11:22, 21 August 2015 (UTC)

Name?
Something I don't see explained: why does this article prefer the term 'magnetoception' and not 'magnetoreception', or perhaps 'biological magnetoreception'? No reference cited - not one - uses 'magnetoceception' in its title. A Pubmed search for 'Magnetoception' receives no results, whereas one for magnetoreception finds a large range of recent papers. As an example of an academic publishing in this field, Professor Hore's papers all use the term 'magnetoreception'. In addition, magnetoreception seems much more natural in English, since it preserves the root 'reception' ('the action or process of receiving something sent, given, or inflicted', according to a dictionary), and in line with other commonly used terms (chemoreception, photoreception, gravitoreception). Blythwood (talk) 18:08, 7 October 2015 (UTC)
 * A very good point. I'd support a move. Martinevans123 (talk) 18:30, 7 October 2015 (UTC)


 * Agree. An admin needs to make the move. --Epipelagic (talk) 19:33, 7 October 2015 (UTC)


 * ✅. I'd noticed this when I edited the article before as well but forgot to move it. SmartSE (talk) 19:51, 7 October 2015 (UTC)
 * Brilliant, thanks. Good to see this fixed so quickly. I've looked through the page history and think this was a mistake by the page's original anonymous creator that never got corrected. Blythwood (talk) 11:43, 24 October 2015 (UTC)

Reception or perception?
Magnetoreception (also Magnetoception) is a sense which allows an organism to detect a magnetic field to perceive direction, altitude or location.

Do we have a magnetic sense defined in this way? I think reception is confused with perception here.

--Stankot (talk) 10:07, 20 April 2016 (UTC)

First principles - even if birds had a compass, it does not explain how they navigate from an unknown location
OK, let's get back to first principles: you are dropped in a rowboat in the middle of an ocean with food and supplies, but the only thing you have to navigate is a magnetic compass and of course the sun. You could easily determine a route to start rowing and maintain that route (assume no drift currents) using dead-reckoning estimating your speed and calculating distance with time. But you would not be able to determine the route to row back to your starting point (roost)- that is the dilemma of this theory that no one is mentioning. More information is needed.

I remember talking to a prominent researcher in this field at Cornell's ornithology lab and he mentioned to me after a lifetime of work that there is another force or energy that the birds are using that remains elusive or yet to be discovered. — Preceding unsigned comment added by 179.33.249.75 (talk) 15:54, 12 March 2017 (UTC)

Reptiles and amphibians
As reptiles are not a monophyletic group (unless you include birds), I suggest changing this section. Or to include birds into this section. I would suggest the former as birds probably require a section to themselves. Carcharias taurus (talk) 15:05, 31 May 2020 (UTC)

Create new section about birds
The section “In homing pigeons” should be merged with the section “In domestic hens” in a single section called “In birds”. In the section “In birds” should be added research on the European Robin, a migratory bird in which magnetoreception with radical pair mechanism has been studied extensively. Also the section “Cryptochromes” could and should be improved. It has been demonstrated that cryptochromes can form free radical pairs also during the night when there is no light to activate them. I could do the necessary editing based on several new references if I am allowed. PHACELIAS (talk) 22:36, 6 January 2022 (UTC)