Simulation of biological shapes as deflated spheres

When a sphere is deflated, a great diversity of shapes are obtained.
It takes several parameters to describe an elastic surface; all the model shapes presented hereafter are obtained by varying only two of them.
Actual biological shapes on the left, and the corresponding Surface Evolver simulations on the right. Eyes candies !


Pollens

Mahonia pollen(1)

Ligustrum pollen(2)

Grass pollen(3)

Tilia pollen(1)

(1) © National Botanic Garden of Belgium, Bruxelles
(2) Image courtesy of the California Department of Justice, California Criminalistics Institute, Sacramento, CA
(3) Picture by S. Dingli

Red blood cells

Discocytes (link) This usual red blood cell shape can also be obtained within a model of pure curvature (a possible link).

Echinocyte (link)

Echinocyte (link)

(link) End of row: knizocytes ("pinched" cells, that normally comprise less than 2 percent of the circulating red cells)

(source: NASA) (direct link)

From M. Bessis in Living Blood Cells and their Ultrastructure, Springer NY 1973

Other

Dessicated pea (link)

Non-bio beach balloon

Gyromitre (some deadly version of the succulent morel)