Document#1B

Below, is a letter from E. Larsen sent to me when she was on sabbatical year in Berkeley. The
text of the letter reads:
24 April '83
Dear Michael,
I just talked to George Oster who had some things to say, as always. He keeps away from
geometrical model because they are, according to him infinite outcomes when you do simulations.
For example, he says that after digitizing the the vertices of cells in the disc and finding out what
the mean cell side length is, the order of cells in which cell side length is equalized is important
in giving a final result. eg if you have 4 cells and you equalized sides of cell 1 then 2 then 3 then
and projected the image it would be a different image than if you started with cell 2 then 4 then 1
then 3. Is this true? He suggested staining discs between 3 rd instar and evagination to see if
their is a [......] sequence of equalizing sides: eg is there a wave as in the eye disc?
In terms of characterizing cell patterns of different discs or the same disc through time he
suggested plotting the relationship between cell perimeter, side length and cell area for cells of a
disc and see if there are disc specific distributions.
Any comments? Can you send me the citation for the article showing division wave in the crypt?
(Cell and Tissue Kinetics)
Regards Ellie

She never understood my work, even the simple things in it. She was peddling things that she did
not understand and could hardly communicate correctly. Nor could she understand the answers.
(Evidently, in her example when the length of cell sides in a polygonal mosaic is consecutively
equalized, the result depends on the choice of the first side.) The "equalization" of sides (but,
rather, cells, equally enlarging their surface area and appearing like a sheet of almost similar
polygons) was my explanation for the process of morphogenesis, when a small, tightly packed
with cells disc develops into the adult appendage. I was convinced that, quite contrary to the
reports published for years by this laboratory in Berkeley, cells do not change their positions in
the tissue, but only change shape, and that this alone should result in the new, adult shape of an
appendage (an elastic transformation). Larsen sold or otherwise peddled this idea to them and,
after 8 years, they confirmed the idea experimentally (see my reference #6 to the article "....... A
Novel Morphogenetic Mechanism"). Alas, in this article they quoted Larsen's article of 1989
(where she plagiarized my Ph.D. research) as a discovery of peculiar cell arrangements in the
discs of Drosophila. She, herself, could not accomplish anything and the grant that she
fraudulently procured was taken away from her.

Here is her letter: