On: Birds had to relearn flight after meteor wiped out...

[Isamu]

I never understood the evolutionary push to develop flight, because I thought of it as an expensive form of transport.

Until this graph, which shows the cost of transport to actually favor flight over terrestrial locomotion.

http://www.wprize.org/images/TuckerCostGraph.gif

[xerxes777 → Isamu]

Better quality: https://i.imgur.com/bBJTGyE.png

[balsam → xerxes777]

Omg horses are more efficient than most cars...?!?!

[erikpukinskis → balsam]

And yet artificial meat being cheaper than animal meat is “inevitable” due to “optimization”.

[yay_cloud2 → Isamu]

Can someone help me understand how to read/interpret this graph? I tried to make sense of it, but I think I was only fooling myself. I need to get planed.

[vanderZwan → yay_cloud2]

The lower on the graph, the more energy efficient. The further right on the graph, the heavier the object.

So the trend is towards more efficiency per kilogram for heavier animals, presumably due to square-cube law[0]. Or maybe the 3/4 scaling law[1][2].

[0] https://en.wikipedia.org/wiki/Square%E2%80%93cube_law

[1] http://mathbench.umd.edu/modules/misc_scaling/page20.htm

[2] https://www.youtube.com/watch?v=DFFVSvAr7Wc

[reubenswartz → Isamu]

Also very handy for avoiding predators.

[cletus → reubenswartz]

Also pretty handy for being a predator (or scavenger).

[soared → Isamu]

Any other info or a higher res for that graph? That totally goes against what I would've assumed! (Trains are wildly inefficient?! Swimming is more efficient than flying or running?)

[mjmahone17 → soared]

I think you’re reading that wrong. Trains are nearly the lowest energy/kg per unit distance travelled, as they’re in the bottom of the graph. Though it’s a bit weird for the x axis to be mass, too.

Basically the y axis is a measure of efficiency. The x axis just spreads out the points so you can compare things of similar mass.

[soared → mjmahone17]

Oh I was reading it wrong, thank you. Its hard to see on mobile. Glad to hear trains are efficient again though.

[saagarjha → soared]

If you have fins and are streamlined like a fish, I'd assume it doesn't take a whole lot of effort to move.

[dluan → Isamu]

I like to think of flight as an artifact of nice pleasant gusts of wind on this particular planet.

[natch → Isamu]

I'd like to see where the Voyager spacecraft fits on that.

[ouid → Isamu]

were you just unaware of how far migratory birds travel?