As a result, Ciro Santilli who likes "lower level stuff", has had many many hours if image manipulation fun with this software, see e.g.:
Where is Anatomy Encoded in Living Systems? by Michael Levin (2022)
Source. - we are very far from full understanding. End game is a design system where you draw the body and it compiles the DNA for you.
- some cool mentions of regeneration
One of the simplest known seems to be: en.wikipedia.org/wiki/Trichoplax
www.u-tokyo.ac.jp/focus/en/articles/a_00220.html "The simplest multicellular organism unveiled" from 2013 mentions Tetrabaena socialis.
- youtu.be/1v6cgSkiHik?t=513 multicellularity is polyphyletic, e.g. evolved separately on plants, fungi and animals.
- youtu.be/1v6cgSkiHik?t=668 describes how unicellular organism choanoflagellates form colony, and how animals are characterized by certain key types of cellular interaction: adhesion, communication, regulation (cell differentiation) and extra cellular matrix production
It is hard to distinguish between colonies of unicellular organism and multicellular organism as there is a continuum between both depending on how well integrated they cells are.
From Wikipedia:and:
Multicellularity has evolved independently at least 25 times in eukaryotes
Complex multicellular organisms evolved only in six eukaryotic groups: animals, symbiomycotan fungi, brown algae, red algae, green algae, and land plants.
Flow Cytometry Animation by StarCellBio (2015)
Source. This is the standard model.
Ciro Santilli's preferred visualization of the real projective plane is a small variant of the standard "lines through origin in ".
For those sphere points in the circle on the x-y plane, you should think of them as magic poins that are identified with the corresponding antipodal point, also on the x-y, but on the other side of the origin. So basically you you can teleport from one of those to the other side, and you are still in the same point.
Ciro likes this model because then all the magic is confined just to the part of the model, and everything else looks exactly like the sphere.
It is useful to contrast this with the sphere itself. In the sphere, all points in the circle are the same point. But this is not the case for the projective plane. You cannot instantly go to any other point on the by just moving a little bit, you have to walk around that circle.
Spherical cap model of the real projective plane
. On the x-y plane, you can magically travel immediately between antipodal points such as A/A', B/B' and C/C'. Or equivalently, those pairs are the same point. Every other point outside the x-y plane is just a regular point like a normal sphere. There are unlisted articles, also show them or only show them.