[Phys-L] raptor physics

[John Denker <jsd@av8n.com>]

Hi Folks --

The following has gotten a fair amount of attention lately.

I find it amusing because is interdisciplinary. Almost
everything I've ever done of any importance has been
interdisciplinary. Being able to "think like a physicist"
comes in handy in situations far removed from the physics
lab. It's good to remind students of this every so often.

Also, since the result is somewhat counterintuitive, it
pays to ask:
 -- Can you show that the situation is much simpler than
  the published paper would have you believe, and the right
  answer can be understood in much simpler terms?
 -- In particular, can you show using high-school physics
  that the result is not exactly wrong, but incomplete and
  highly open to misinterpretation?

I claim if you frame things just right, you can explain
what's going on to high-school students using simple basic
physics. I am not claiming the students could figure it out
on their own. It might take a smart person half a day to
discover how to frame things just right.

For my take on this, see next message. Some time tomorrow.
In the meantime y'all can puzzle over it.

> Peregrine Falcons capture their prey in flight by
> 'stooping' at very high speed, but why? Researchers used
> complex computer models to examine the benefits of this
> approach, and found that the main advantage of stooping
> was the ability to make quicker turns because of the high
> aerodynamic forces at such speed (and the compact shape
> with wings pulled in also allows quicker maneuvering). In
> essence the high speed is like a coiled spring, building
> up pressure that can be used to make the turns needed to
> follow the evasive maneuvers of the prey. This only works
> with extraordinarily precise vision and control, and the
> physical adaptations to be able to withstand such extreme
> pressures, and the Peregrine Falcon has evolved all of
> those things.

Reference: Mills et al 2018. "Physics-based simulations of
aerial attacks by peregrine falcons reveal that stooping at
high speed maximizes catch success against agile prey."

PLoS Computational Biology 14(4)
https://doi.org/10.1371/journal.pcbi.1006044

Non-technical coverage:
https://www.youtube.com/watch?v=CKmfti3obhA

https://www.science.org/content/article/peregrine-falcons-maneuver-best-when-dive-bombing-more-300-kilometers-hour