How the shape of an apple is formed

Apple is one of the oldest and most recognizable fruits in the world

How did the apple grow such a unique shape?

Now, a team of mathematicians and physicists understand the growth and shape of the apple tip through observations, laboratory experiments, theories and calculations

This paper was published in the journal "Nature Physics"

"The shape of living things is usually focused on the existence of structures," said Mahad, Professor of Applied Mathematics, Lora de Valpine, England, Professor of Physics, Organic and Evolutionary Biology, and Harvard University's John A.

Mahadevan has developed a simple theory to explain the shape and growth of apples, but when researchers were able to connect observations of real apples at different growth stages and gel experiments that simulate growth with theories and calculations, the project began to bear fruit Fruit

The research team collected apples of different growth stages from the orchard of Peter College of the University of Cambridge (the alma mater of the famous apple lover Sir Newton)

Using these apples, the research team mapped the growth of dimples (which they call "tips") over time

In order to understand the evolution of the shape of the apple, especially the evolution of the apple tip, the researchers turned to a long-standing mathematical theory, the singularity theory

"The exciting thing about the singularities is that they are universal

On the basis of this theoretical framework, the researchers used numerical simulations to understand the growth difference between the core driving force formed by the fruit skin and the top

"It is particularly exciting to be able to control and replay single-point morphogenesis in the laboratory with a simple material kit," said Aditi Chakrabarti, a postdoc at SEAS and also Co-author of this paper

The research team discovered that the underlying fruit anatomy and mechanical instability may play a combined role in the process of producing multiple points in the fruit

"Morphogenesis, the origin of shape, is one of the major problems in biology," Mahadewen said

The research was co-authored by Sifan Yin, a visiting student at Tsinghua University, and Eric Sun, a former undergraduate student in the laboratory

DOI

10.
1038 / s41567-021-01335-8