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Steve Jobs claimed on video that a bicycling human is more efficient at locomotion than any other species can manage. He repeated it separately on video, and in writing. The quote is still oft repeated. A poster print run raised 5k USD on Kickstarter.

Here's a transcription:

I think one of the things that really separates us from the higher primates is that we’re tool builders. I read a study that measured the efficiency of locomotion for various species on the planet. The condor used the least amount of energy to move a kilometer. And humans came in with a rather unimpressive showing about a third of the way down the list. It was not too proud of a showing for the crown of creation.

That didn’t look so good. But then, somebody at Scientific American had the insight to test the efficiency of locomotion for a man on a bicycle. And a man on a bicycle completely blew the condor away, completely off the top of the chart. And that’s what a computer is to me. What a computer is to me, is it’s the most remarkable tool that we’ve ever come up with. It’s the equivalent of a bicycle for our minds.

Is a human on a bicycle really overwhelmingly more efficient at moving from place to place than any other species?

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    I would think you would need to define the conditions better. I have a hard time believing a human on a bicycle can beat a soaring bird in an area of thermals.
    – Loren Pechtel
    Commented Apr 19, 2015 at 22:02
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    @LorenPechtel It's indeed hard to define a "standard atmosphere", but I imagine it's in the spirit of the question for the birds to get no thermals, the bicycles no downhills, the fish no currents and the earthworms no landslides.
    – Anko
    Commented Apr 19, 2015 at 22:08
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    Speed runs and the like are usually done over a loop to eliminate things like downhills & currents. However, the soaring bird can soar in a loop. (Or, for that matter, substitute "glider pilot" for "bird".)
    – Loren Pechtel
    Commented Apr 19, 2015 at 22:21
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    Well, to travel from UK to Africa, I'm quite sure birds are more efficients than cyclists...
    – TZDZ
    Commented Apr 20, 2015 at 13:19
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    Comparing the energy efficiency of human and animal locomotion, one should also perhaps include the energy used to provide the required nutrition. With our incredibly inefficient agricultural industry and nourishment distribution networks, even using a car may leave a smaller carbon footprint than riding a bike. The carbon footprint of a Big Mac (4kg) is equivalent to driving my car 45km. With the provided 495kcal of energy, I would probably only be able to ride about 20-30km on a bicycle.
    – Tor-Einar Jarnbjo
    Commented Apr 20, 2015 at 14:13

1 Answer 1

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The quoted statement says "energy to move a kilometer".

On an "energy to move a kilometer" basis, the statement is definitely false.

Acccording to Dr. Karen Oberhauser, a tagged monarch butterfly has been confirmed to travel 265 miles in one day.

According to How Much Fuel Do Monarchs Burn? reporting Dr. David Gibo's research:

On 140 milligrams of fat a monarch butterfly has enough energy to continuously flap its wing flying for 44 hours and to soar or glide for 1040 hours!

So the butterfly is using at most 3 milligrams per hour.

For comparative human statistics, use this excercise calorie calculator

For a 110 pound (50kg) human:

bicycling 16-20 miles per hour 599 dietary calories (kilocalories) are used per hour. This corresponds to 67 grams (67,000 milligrams) fat per hour.

bicycling at an unspecific "greater than 20 mph" racing speed is 798 calories per hour. This corresponds to 89 grams (89,000 milligrams) fat per hour.

Humans use more than 1000 times as much energy per kilometer as monarch butterflies, even considering the record distance on a bicycle for a day is 521 miles, about twice the butterfly's record.

Note: although the quoted statement clearly says "energy to move a kilometer", and nowhere suggests that mass moved should be considered, another way to consider efficiency is

(energy used)/((mass of organism)(distance traveled))

On this basis, swimming animals have been found to be the most efficient animals.

enter image description here

All credit to Brad J. Gemmell, Passive energy recapture in jellyfish contributes to propulsive advantage over other metazoans Proceedings of the National Academy of Sciences of the USA volume 110 pages 17904–17909.

As reported in Eel migration to the Sargasso: remarkably high swimming efficiency and low energy costs, the eel is very efficient.

Particularly, its efficiency is calculated to be 0.5 kilojoules/kilometer/kg.

Let's compare this to a human bicycling.

I'll use a 50 kg human, 29 kph (18 mph), 599 kilocalories per hour.

599 kilocalories/hr is 2500 kilojoules/hr.

This corresponds to 86 kilojoules/kilometer.

Or 1.7 kilojoules/kilometer/kg

Eel is more efficient by a factor of 3.

(From the jellyfish article it can also been seen that a species of jellyfish has about the same efficiency of the eel. Large marine animals such as whales do not seem to have been considered.)

See also Swimming speed, respiration rate, and estimated cost of transport in adult killer whales, which shows that at an optimal speed of around 3 meters/second, killer whales have an efficiency of 0.78 kilojoules/kilometer/kg. Better than a human on a bicycle, but not quite as good as an eel.

According to Energy in Nature and Society: General Energetics of Complex Systems by Vaclav Smil, at page 103

for a 15-t gray whale is 0.4 J/m kg (if this exponent holds than a baleen whale would need [less than] 0.1 J/m kg)

See also Comparative analyses of animal-tracking data reveal ecological significance of endothermy in fishes which shows some sharks have efficiency in the 0.1-0.2 J/m kg range.

In conclusion, a human on a bicycle is NOT the most efficient. Whether the quote is analyzed literally on an "energy to move a kilometer" basis, or alternatively as energy per distance per mass of organism, there are more efficient species.

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    This is a good answer, but it would be improved by showing how many grams of fat are burnt during a bicycle ride, or even bicycle exercise, rather than cardio, over the period of an hour. Preferably on a flat surface to avoid bias.
    – Zibbobz
    Commented Apr 21, 2015 at 17:01
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    @Zibbobz even basal metabolism (just resting in bed) is 1500 calories per day for women, which corresponds to 7 grams fat per hour. The butterfly still would have that beat by a factor of 1000. ncbi.nlm.nih.gov/pubmed/528122
    – DavePhD
    Commented Apr 21, 2015 at 17:18
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    It seems like a very strange measure of efficiency to not factor in the amount of mass moved. If one factors in mass moved, the human on a bicycle beats the butterfly by a large margin, assuming your estimate of 1000 times energy usage.
    – Muhd
    Commented Apr 21, 2015 at 19:46
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    @Muhd If we factor in mass, the eel or jellyfish would be most efficient, see jeb.biologists.org/content/208/7/1329.full#T1 and pnas.org/content/110/44/17904/F1.expansion.html
    – DavePhD
    Commented Apr 21, 2015 at 20:02
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    @gerrit: You're forgetting, though, that those vehicles only travel efficiently on pre-prepared surfaces (roads &c). For a randomly chosen trip between two points (on land, of course), there's a pretty good chance the bike won't be able to do it at all. If you want to look at special cases, for water transport, or in certain areas like dry lake beds, a sailing craft is far more efficient than a cyclist, since it takes zero internal energy to move, and only a tiny amount to trim sails.
    – jamesqf
    Commented Apr 22, 2015 at 18:47

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