Identify this scifi book

[Jayjay]

It's about humanity changing its genetics to adapt to different worlds. One part of it was transforming man to live in Neptune or some other planet in our solar system. Another part of it was future humans in some far future getting stranded on a planet with nothing but microbial life, so they change themselves into microbe-sized humans. written maybe in 1950s or 60s.

 

[Keith&Co.]

Book?

I know a short story, Surface Tension by Blish.
The colonizing ship crashed on a water world....


1952

 

[bilby]

Maybe Last and First Men by Olaf Stapledon? But that was earlier - it's from 1930.

 

[Jayjay]

Book?

I know a short story, Surface Tension by Blish.
The colonizing ship crashed on a water world....


1952

Close enough! The book I was searching for was a collection including that one and other similarly themed stories by Blish,  The Seedling Stars. Thanks.

 

[Jobar]

I read that one back in my teens.