[Phil V.]

"I found that the gas release was indeed rhythmic, with a period of precisely 24.66 hours, a Martian day . . ."

I'm curious about what the temperature variation of the "soup" was. Unless it was constant and protected from the day-night Martian temperature swings then the period could reflect a 24.66 hour Martian temperature cycle as opposed to a bio-rhythm . . .

[NotQuiteCricket]

I don't know if they controlled for temperature or not or if temperature would be something that would cause the reaction that they noticed.

Here is a link to the article:
http://www.space.com/news/spacehistory/viking_life_010728-1.html

[Starrgaizr]

"I found that the gas release was indeed rhythmic, with a period of precisely 24.66 hours, a Martian day . . ."

"That night, too, there was another jetting out of gas from the distant planet. I saw it. A reddish flash at the edge, the slightest projection of the outline just as the chronometer struck midnight..."