[yazantapuz]

If i remember right, according to one of Asimov's Foundation sequels, the Earth was unique due to its high level natural radioactivity, which allowed it to develop an ecosystem more vibrant than any other planet in the galaxy.

[sleepy_keita]

Was just rereading - it was the radioactivity and the large natural satellite that was unique in his universe. Tides are interesting because once you have life in the oceans, it's a kind of forcing function to adapt to land conditions

[actionfromafar]

Forcing function + making a stretch of land which is neither dry nor enterily wet. A gradient. If there are no tides the leap life has to make is much bigger.

[euroderf]

And perhaps the advantages of this gradient extend up as far as aquatic apes.

[actionfromafar]

Not sure what this means.

[IAmBroom]

I assume they are referencing the long-debunked theory that man evolved from a line of apes that became semi-aquatic for a while.

[euroderf]

Yup that's where I was aiming. Is it thoroughly debunked ? It's a cool idea.

[piker]

Fascinating

[stavros]

Why are tides a forcing function? Marine life has been perfectly content just not going near a beach.

[JumpCrisscross]

> Why are tides a forcing function?

"Nucleotide formation and polymerization are both more favored thermodynamically when subunit and nucleotide concentrations increase and the water concentration decreases (i.e., at low water activity)" [1].

Tide pools provide a regularly-cycling low-water and high-water environment. (And you get thermocycling, nutrient refreshment, and a path to the oceans, too.)

They're not a forcing function, generally, because we don't know how life formed. But I believe they're close to one in a RNA-first or metabolism-first origin-of-life universe.

[1] https://www.nature.com/articles/s41467-018-07389-2

[stavros]

Very interesting, thank you!

[sleepy_keita]

I was thinking more on the lines of "if marine life never found itself stranded on land, it wouldn't need to evolve to survive on the land"

[patwolf]

There was a mention of something like that in Starship Troopers as well.

Heinlein describes life on an earth-like planet with low radiation as being "like a kid who takes ten years to learn to wave bye-bye and never does manage to master patty-cake".

[blueflow]

Wasn't Asimov a science fiction writer?

[dredmorbius]

He was a popular writer of both fiction and nonfiction, had a PhD in chemistry, and wrote on numerous topics, including science, history, Shakespeare, and the Bible.

He and Arthur C. Clarke had a (tongue-in-cheek) agreement:

The feelings of friendship and respect between Asimov and Arthur C. Clarke were demonstrated by the so-called "Clarke–Asimov Treaty of Park Avenue", negotiated as they shared a cab in New York. This stated that Asimov was required to insist that Clarke was the best science fiction writer in the world (reserving second-best for himself), while Clarke was required to insist that Asimov was the best science writer in the world (reserving second-best for himself). Thus, the dedication in Clarke's book Report on Planet Three (1972) reads: "In accordance with the terms of the Clarke–Asimov treaty, the second-best science writer dedicates this book to the second-best science-fiction writer."

<https://en.wikipedia.org/wiki/Isaac_Asimov#Other_authors>

[baxtr]

He was both a science and science fiction writer. Check out "View From a Height" for example. An excellent book.

https://en.wikipedia.org/wiki/View_from_a_Height

[euroderf]

He wrote a book about jokes and how to tell them. Quite good.