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This is highly, highly dubious without a physical explanation. Or with representative statistical data. Magnetic and electric fields do not interact much with

This is highly, highly dubious without a physical explanation. Or with representative statistical data. Magnetic and electric fields do not interact much with biological matter, so something 'special' needs to be shown here before there is a point. This should be treated with utmost caution without statistical and physical proof.

samatman 5y ago
This is categorically false, both magnetic and electric senses in other animals have been proven to exist, pigeons for magnetism and the electric organ in bony fishes. It's not at all physically implausible that crabs sense some electric or magnetic character in the surrounding water through their antennae or some other organ. Electroreception is known in bees, why not crabs? This could easily be the first evidence of that. https://en.wikipedia.org/wiki/Electroreception https://en.wikipedia.org/wiki/Electroreception
- beeforpork 5y ago
  But I am not saying that the phenomenon does not exist. I am saying that I am lacking evidence in the article. Evidence could be statistical (if we don't know how yet) or physical (if we do know how, like, a sense was identified). But for me, pointing to a bunch of crabs on a cable and making assumptions is not enough.
  - samatman 5y ago
    No, you were saying it's inherently dubious without either statistical or physical evidence. I'm replying, no, there's nothing dubious about it. Which doesn't mean it's accurate. Biology has always prominently featured observation from life, and this is, in general, how the field first starts to suspect that, say, bees can sense electric fields. Experiments on crabs might and should follow, but your skepticism isn't grounded in anything here.
    - beeforpork 5y ago
      > No, you were saying it's inherently dubious without either statistical or physical evidence. Yes, exactly, because at least counting the crabs and comparing the count with other clusters of crabs would show whether there 'is something'. Missing accuracy is not my problem, it's missing 'there is something' vs. 'there is nothing'. Without any statistical data, there is nothing to talk about, not in biology either, which is also science. Skepticism is very important. I challenge them to count crabs on cables and compare with crab counts not on cables, and then make a case. That's all.
      - deleted 5y ago
        [deleted]
    - schiffern 5y ago
      >Experiments on crabs might and should follow This is the follow-up experiment. https://www.mdpi.com/2077-1312/9/7/776 https://www.mdpi.com/2077-1312/9/7/776 As usual with modern science journalism, it's necessary to click through and read the actual research paper. Otherwise, one will be totally lost. As for samatman's concerns, the paper uses standard experimental controls and statistical analysis, as expected.
mattkrause 5y ago
That's not right: electric and magnetic fields are used to alter brain activity, even non-invasively. Transcranial magnetic stimulation uses pulsed magnetic fields produced by a strong electromagnet. It's currently an FDA-approved treatment for depression and a pretty common research tool. The fact that it has (some) biological effect is pretty clear: aim it at motor cortex and you can make someone's finger (leg, etc) twitch! Transcranial electrical stimulation (tES) is a family of techniques that apply weak electric current to the scalp to affect brain activity. These include tDCS (with Direct Current) and tACS (Alternating Current). While their effectiveness has been debated, my group has collected data demonstrating robust effects on the activity of neurons, even deep in the brain. Check out Figure 1 of this paper: https://www.pnas.org/doi/10.1073/pnas.1815958116 https://www.pnas.org/doi/10.1073/pnas.1815958116 It's not always that simple, and it interacts in complicated ways with ongoing brain activity, but it does do something too. You can get much strong effects if the electrodes are inserted directly into the brain (or muscle) too but it's not all the case that EMFs are biologically "inert".
aaron695 5y ago

samatman 5y ago

This is categorically false, both magnetic and electric senses in other animals have been proven to exist, pigeons for magnetism and the electric organ in bony fishes. It's not at all physically implausible that crabs sense some electric or magnetic character in the surrounding water through their antennae or some other organ. Electroreception is known in bees, why not crabs? This could easily be the first evidence of that. https://en.wikipedia.org/wiki/Electroreception https://en.wikipedia.org/wiki/Electroreception

beeforpork 5y ago
But I am not saying that the phenomenon does not exist. I am saying that I am lacking evidence in the article. Evidence could be statistical (if we don't know how yet) or physical (if we do know how, like, a sense was identified). But for me, pointing to a bunch of crabs on a cable and making assumptions is not enough.
- samatman 5y ago
  No, you were saying it's inherently dubious without either statistical or physical evidence. I'm replying, no, there's nothing dubious about it. Which doesn't mean it's accurate. Biology has always prominently featured observation from life, and this is, in general, how the field first starts to suspect that, say, bees can sense electric fields. Experiments on crabs might and should follow, but your skepticism isn't grounded in anything here.
  - beeforpork 5y ago
    > No, you were saying it's inherently dubious without either statistical or physical evidence. Yes, exactly, because at least counting the crabs and comparing the count with other clusters of crabs would show whether there 'is something'. Missing accuracy is not my problem, it's missing 'there is something' vs. 'there is nothing'. Without any statistical data, there is nothing to talk about, not in biology either, which is also science. Skepticism is very important. I challenge them to count crabs on cables and compare with crab counts not on cables, and then make a case. That's all.
    - deleted 5y ago
      [deleted]
  - schiffern 5y ago
    >Experiments on crabs might and should follow This is the follow-up experiment. https://www.mdpi.com/2077-1312/9/7/776 https://www.mdpi.com/2077-1312/9/7/776 As usual with modern science journalism, it's necessary to click through and read the actual research paper. Otherwise, one will be totally lost. As for samatman's concerns, the paper uses standard experimental controls and statistical analysis, as expected.

mattkrause 5y ago

That's not right: electric and magnetic fields are used to alter brain activity, even non-invasively. Transcranial magnetic stimulation uses pulsed magnetic fields produced by a strong electromagnet. It's currently an FDA-approved treatment for depression and a pretty common research tool. The fact that it has (some) biological effect is pretty clear: aim it at motor cortex and you can make someone's finger (leg, etc) twitch! Transcranial electrical stimulation (tES) is a family of techniques that apply weak electric current to the scalp to affect brain activity. These include tDCS (with Direct Current) and tACS (Alternating Current). While their effectiveness has been debated, my group has collected data demonstrating robust effects on the activity of neurons, even deep in the brain. Check out Figure 1 of this paper: https://www.pnas.org/doi/10.1073/pnas.1815958116 https://www.pnas.org/doi/10.1073/pnas.1815958116 It's not always that simple, and it interacts in complicated ways with ongoing brain activity, but it does do something too. You can get much strong effects if the electrodes are inserted directly into the brain (or muscle) too but it's not all the case that EMFs are biologically "inert".

aaron695 5y ago