According to the Physics Factbook, nerve impulses travel at speeds anywhere from 1 meter per second up to around 100 meters per second. Blue whales reach up to around 30 meters long.

For a full-size blue whale, this means that a nerve impulse to move the tail muscles could take from 0.3 seconds to 30 seconds to reach the tail. While I'd imagine factors such as myelination and other adaptations function to keep this closer to the 0.3 second measure above, this is still a best case scenario, and would certainly be a noticeable delay were it a human being.

Do large organisms experience meaningful delays when moving their most distant appendages?

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    $\begingroup$ Humans have a delay of around 0.3 seconds for moving arms (training helps for many situations). Part of that is the transmission speed, but there's also the serial problem - neurons arranged in a sequence gain considerable delay. That's why we have so many "automatic" systems that don't rely on inputs going from e.g. leg to the brain, get processed and transmitted back. You usually don't notice because your brain lies to you all the time - there's some real fun experiments that cheat your brain to thinking reactions happen before their stimulus (e.g. pressing a button to light a bulb). $\endgroup$
    – Luaan
    Feb 7, 2019 at 18:41

1 Answer 1


Yes, larger animals do experience larger delays in movement.

There have been studies of size difference vs sensorimotor delays in terrestrial mammals, https://www.ncbi.nlm.nih.gov/pubmed/30158304

enter image description here That graph is for innate reflexes of a needle to the hind versus a kick-time. Perhaps no one dared to prick a blue whale.

Elephant vs shrew, heartbeat of 30 vs 1500 BPM, elephant 50 times slower than the shrew. Larger animals compensate with a better ability to predict physics and kinematics using their larger brain.

There are other kinds of movements which have more complex neural pathways that the graphs of pin-prick reflexes, that are even slower compared to size, you can study the physiology of eye to hand response in humans which varies from 120ms to 270ms for different humans.

It does have an effect on survival for example with a mongoose versus a snake, the mongoose has more versatile and faster reactions. enter image description here

There are also weasel attack videos on the web. some graphs here

enter image description here

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    $\begingroup$ Good presentation. Would benefit from a #Yes, larger animals do experience larger delays in movement. Introduction $\endgroup$
    – Wyrmwood
    Feb 7, 2019 at 17:06
  • $\begingroup$ "heartbeat of 30 vs 1500 BMP" I think you meant "BPM (beats per minute)"? $\endgroup$
    – Andrew T.
    Feb 8, 2019 at 4:54
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    $\begingroup$ It may be valuable to point out that (most) invertebrates have a far slower conduction velocity than vertebrates due to the former not employing saltatory conduction. $\endgroup$
    – forest
    Feb 8, 2019 at 8:56
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    $\begingroup$ It's a shame humans are not on the pain reflex graph, and that there's no non-human data for eye-hand reflex. $\endgroup$
    – OrangeDog
    Feb 8, 2019 at 14:22

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