Are there any right angles or natural grids in nature?

Do crystals count as "nature?"

In theory, as the atom carbon is capable of forming 4 bonds with 4
other atoms, so to get the best arrangement to achieve a widest
distance between all the atoms is to achieve a 90 degrees angle
between the bonds on a planar axis, am not sure if this answers what u
are looking 4.

Many plants have right angled growth patterns --  complex leaves or
branches on trees.

Here are some sites where you can explore patterns in nature.

Patterns in nature
http://www.uen.org/themepark/html/patterns/naturepatterns.html

http://atschool.eduweb.co.uk/sirrobhitch.suffolk/patterns_nature/

Photos of patterns in nature
http://www.californiapictures.com/naturepatterns.html

ff.lakeheadu.ca/~emp/photos/patterns.html 

http://www.nhpa.co.uk/nhpa/az123/az123.htm

some awesome ice photos
http://members.aol.com/drhaw/patterns.html

Actually, the 4 bonds in a carbon atom take place in 3-D space, so
they are at 109.5 degrees rather than 90 degrees in a methane molecule
(check out http://www.education.eth.net/acads/chemistry/carbon_bonds-I.htm
as well as http://www.pen.k12.va.us/Anthology/Div/Winchester/jhhs/math/lessons/trig/bonds.html).
For more complex and asymmetric (and less odorous) molecules, the
angles may not all be equal.

There are some grids in nature caused by crystalline growth and
similar behaviours. For example the Giants Causeway in Ireland: see
http://www.giantscausewayofficialguide.com/welcome.htm.

Also what about Snowflakes?

The mineral galena (lead sulfide) has a nice cubic structure.  That's
not it's only crytal structure, but it's easy to recognize in the
cubic form.

There are absolutely natural grids in nature.  Even ones that are
visible on scales that we deal with every day.  For example, in my
research, we take small brass spheres, put them in a flat dish like
cell, and shake them up and down.
When the peak acceleration is around 3-4 times that of gravity, we get
a pattern called squares.  It literally looks like a waffle in the
cell.  And these squares will occur in round cells or cells of any
shape (although the squares do try to make themselves perpendicular to
the walls.)  They are typically 2-3 cm across, but since they are in
the period doubled regime, they appear 1-1.5 cm across (the eye can't
resolve the two peaks separately, so you see them both.

If you are interested further in these patterns, there is a rich set
of technical literature deacribing them.  E-mail me for references or
other information.

Regards,
Martin Melhus
(aeronaut)

Of course, bees make honeycomb (natural hexagon grid).
Spiders make very intricate grids with their webs.

Nature tends to stick with whatever works best. In cases where a right
angle or grid is the most functional formation, that's what nature
will go with.

In the animal and plant world, right angles do exist, but seem to be
the exception rather than the rule. If you think about it, right
angles are not always the most effective structure for support in
nature. For us humans, it works great for buildings. To support the
roof over our heads, a right angle is perfect since it takes most of
the force directly into the ground. But of course, a building is
stationary. It isn't subject to a lot of lateral force save perhaps
for wind. Nature, however, tends to a bit more rough. Having joints at
an angle allows for greater flexibility to accomodate varying stress.

Grids, by which I am interpreting regular patterns, are much more
common. The Fibbonaci (spelling?) series is a classic example of
methematical patterns in nature, especially in plant life.