Aleksandar Mihajlovski said:

> You can check if your honeybees are different, and
> what they "think" about ventilation.

> Make a hive which have ALL sides made from mesh
> (screen), also bottom and top.

Hold on there... Was that:

a)  A test of the bees' reaction to increased airflow and ventilation?

b) Nothing but a test of the bees' obsessive-compulsive need to
    plug up what they viewed as "cracks"?

I'd submit that it was (b), not (a).

They can't fit their heads through 8-mesh, so they filled
up the "cracks".

Consider the lowly propolis trap.  Put it in, and the
bees will happily fill it up.  If placed properly, it blocks
no ventilation at all.

If you want to test airflow, you can rig fans driven by
solar panels, and increase airflow without increasing
openings.  (Gotta cover the fans with mesh, or you
get bee puree...)

I have inner covers with built-in upper entrances cut
in one side of the "front" with widths than vary from 1
inch to as much as 6 inches wide.  (I was "testing")

Never saw any hive propolize more than the usual amount
around the inner cover edges, and never saw the opening
reduced by propolis.  Same for the lower entrance.

...and I DID get some propolis on my screened bottom board mesh.
Toward the back corners of the hive, furthest from the entrance,
never towards the front.  My homebrew "Klugen-Bottom" (TM)
(an integrated screen bottom board, sticky paper shelf, bottle opener,
and anti-raccoon/possum spike strip weapons system) lets me slide
out the screen for debris cleaning, and the sliding was sometimes
more difficult than I would like until I got smart and coated the edges
of the screen frame (like a window screen frame) with a thin coat of wax.

...which is a good trick for frame ears and their rests if you
have lots of extra wax you don't feel like selling and lots
of time this winter - anything you give a nice coating of
wax (dip, paint, whatever) is not propolized nearly as much
(if at all) as unwaxed surfaces of the same type.

Wax works like a champ in observation hives too.
Less goo is good.

                jim