
American paleontologist Neil Shubin’s 2008 pond scum evolution diagram. [2]

American paleontologist Neil Shubin’s 2008 pond scum evolution diagram. [2]

In terminology, pond scum, from the German scum "foam", is a semi-recent phrase, a possible cross between Charles Darwin’s 1871 “warm pond” origin of life model and Stephen Hawking’s 1995 “humans = heated chemical scum” model, often employed to dehumanize or derogate theories on human origins, often seen in religion vs science debates.

Quotes
The following are related quotes:

“The human race is just a chemical scum on a moderate-sized planet, orbiting around a very average star in the outer suburb of one among a hundred billion galaxies.”
— Stephen Hawking (1995), interview with Ken Campbell [1]

“Where do our lineages stop? Does it continue to 3.8-billion-year-old pond scum, and beyond? Everybody agrees that there own lineage goes back go some point in time, but just how far back is the issue.”
— Neil Shubin (2008), Your Inner Fish [2]

“Our country’s Declaration of Independence specifically states that all men are ‘created’ and that they are endowed ‘by their Creator’ with basic human rights. Yet there is an ongoing effort in society to eliminate the very idea that we have a Creator. We did not evolve from pond scum, but were made in the image of God.”
— Ray Comfort (2013), commentary as producer of the film Evolution vs. God (Ѻ)

See also
● Bag of chemicals

References
1. (a) Hawking, Stephen. (1995). "Interview with Ken Campbell", Reality on the Rocks: Beyond Our Ken.
(b) Pross, Addy. (2012). What is Life? How Chemistry Becomes Biology (pg.viii). Oxford University Press.
(c) Tallis, Raymond. (2013). “You Chemical Scum, You”, Philosophy Now, May/Jun.
2. Shubin, Neil. (2008). Your Inner Fish: a Journey into the 3.5-Billion-Year History of the Human Body (pond scum, pg. 178). Random House.