
How do wombats make cubed poo? - fortran77
http://meetings.aps.org/Meeting/DFD18/Session/E19.1
======
antonvs
> ...provides insight into new manufacturing techniques for non-axisymmetric
> structures using soft tissues.

I'm glad to hear that future technology may use the same manufacturing
techniques as the the cubed poo of the wombat.

~~~
gumby
For inexpensive factory production of sugar cubes, broth cubes and the
like...yum!

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ISL
Many wombats died to bring us this information.

(These wombats died in car accidents, and their bodies used to learn more
about wombats: [https://phys.org/news/2018-11-scientists-wombats-cubed-
poop....](https://phys.org/news/2018-11-scientists-wombats-cubed-poop.html))

------
praptak
A more digestible explanation:
[https://www.nationalgeographic.com/animals/2018/11/wombat-
po...](https://www.nationalgeographic.com/animals/2018/11/wombat-poop-cube-
why-is-it-square-shaped/)

------
londons_explore
Does cubic poo help the wombat in any way?

Does it use poo cubes to build things?

Edit:. A quick internet search suggests they poop in high up places to mark
territory, and presumably the more typical round poop would fall off high up
rocks and be a bad marker.

~~~
Jedd
Yes, as cmroanirgo notes, they're renowned for this, and sometimes it can be
quite amazing to 'spot the poo' after you've left some object out for only a
day or two. I see them regularly on 50mm wide poly (irrigation) pipe - the
accuracy of placement is astounding.

Wombats are territorial, and very regular in their nightly movements. The
cubic poo may be in part a simple consequence of their body shape (squat,
narrow, long - evolved to wiggle into tight holes leaving only their
impenetrable back plate exposed to would-be predators through the day), or, as
you observe, assisting in perching scat with less risk of it being moved.

As I understand it, the extra height allows for other animals to more easily
detect (by smell, I'm guessing, but may be visual as well) their presence in
the area - presumably with the intent that those other animals keep away.

~~~
benj111
"and very regular in their nightly movements"

I see what you did there.

------
conformist
David Hu (last author) is famous in the fluid dynamics community.

See also [https://blogs.scientificamerican.com/guest-
blog/confessions-...](https://blogs.scientificamerican.com/guest-
blog/confessions-of-a-wasteful-scientist/)

~~~
catbird
Prof. Hu has a delightful pop-science book about animal-inspired engineering
called "How to walk on water and climb up walls."

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fredley
I look forward to the authors receiveing their IgNobel prize!

~~~
qbonnard
> NOTE: This the SECOND Ig Nobel Prize awarded to Patricia Yang and David Hu.
> They and two other colleagues shared the 2015 Ig Nobel Physics Prize, for
> testing the biological principle that nearly all mammals empty their
> bladders in about 21 seconds (plus or minus 13 seconds)

[https://www.improbable.com/ig-
about/the-2019-winners/](https://www.improbable.com/ig-
about/the-2019-winners/)

~~~
jillesvangurp
That abstract is a work of art. "This study addresses the long-standing
mystery of cubic scat formation"

------
benj111
Quote of the day:

"By emptying the intestine and inflating it with a long balloon, we found that
the local strain varies from 20 percent at the cube's corners to 75 percent at
its edges"

Edit: Square sausages anyone? (I'm aware of Scottish square sausages)

------
IgorPartola
Somewhat off topic, but the podcast Wow in the World did an excellent episode
on this. It is a podcast aimed at children that is all about science and is
not annoying to listen to as an adult. Highly recommend.

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gumby
I don’t this would really be the result, but it would be cool if this led to
factories with more organic shapes and processes. The current state of the art
factories would be amazing but somewhat recognizable to a Victorian time
traveler (well, maybe not chip fabs, of maybe them too).

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cryptofits
That's the kind of titles that makes me love HN so much

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equalunique
EDIT: Nevermind.

>This study addresses the long-standing mystery of cubic scat formation and
provides insight into new manufacturing techniques for non-axisymmetric
structures using soft tissues.

I hope they didn't kill a wombat just so they could inflate it's lower
intestine like a balloon & write about the shape it made. Seems like an
unethical waste, no?

~~~
jasonhong
It's answered in the linked abstract:

"...derived from veterinary euthanized individuals following motor vehicle
collisions in Tasmania, Australia"

------
Sniffnoy
This seems to be an abstract for a talk rather than the actual full paper?

~~~
analog31
Correct. At least in physics, there's no paper. The abstract is what's
submitted to the conference, and gets published before the conference begins.
Peer review is limited to deciding whether your talk gets into the conference
schedule or not, slotted into a different division of the conference, or
perhaps to a poster session.

You could contact the author and see if they have a preprint or something to
share.

The intent is to provide an outlet for "lesser" stature work, student
projects, or preliminary results en route to writing a full paper. I was a
physics student 25 years ago, and there was an informal culture of "everybody
gets to publish." You were pretty much guaranteed a slot at one of the
conferences, even if it was a poster session in a dark hallway alongside the
guys who were proving that quantum mechanics was a hoax. That way, nobody
could say, "they refused to publish me." And the field was never so crowded
that there wasn't room for a few of those abstracts.

How it should be done in the contemporary era is of course an open question.
;-)

