A remarkable read. Benny Shilo brings to life developmental biology. And in so doing, we see the underlying uniformly uniform, and ancient mechanisms which drive the form of all heads, eyes, fingers, wings, segments and patterns; as well as causing cancer, cell death and cell repair. ‘Relevant complexity’ indeed.
This is a tour de force – never tricky for sake of it; even more challenging concepts are mostly made straightforward to understand. Not least because they are illustrated by simple analogies, rich metaphors, clever pictures and lovely photographs. And there are some amazing things to learn.
These paragraphs (lightly edited) from p72 rather blow the mind:
The preservation of developmental pathways across the entire spectrum of multicellular organisms means they were present in the primordial multicellular organism and have thus been conserved to the present day in all organisms which descended from it.
Although this ancestral organism does not exist today, we can imagine it based on the genes and developmental pathways which have been conserved in all present multicellular organisms.
It was quite an elaborate creature, displaying a segmented body, with possible differences between segmented regions. This organism had appendages from either all or some of them. It had primitive eyes that can could sense light, and probably had an immune system which protected it from common infections by bacteria of fungi.
Flies, worms, frogs, fish, birds, human beings – everything in the animal kingdom descended from this ancestral segmented, multi-limbed creature with its rudimentary eyes. And the gene which placed its eyes in the right place and ensured they were connected to its brain, continues to do the same job in every species – invertebrate or vertebrate, unchanged for 800 million years.
You finish the book marvelling at the fact that we share most of our fundamental developmental principles and mechanisms with fruit flies. Because the same simple, but incredibly intricate, signalling systems build every living animal.
Fabulous – the man is a wonder and so is his work. This book and subject deserves a much wider audience. I suggested it to (and got it from) our library, so here’s hoping many more people will read it.