Comma needed? It's always so tough to know.

[SashaMcallister]

Bacteria on an anthill couldn’t even begin to comprehend the nature of ants let alone the sprawling megacity surrounding it.

or

Bacteria on an anthill couldn’t even begin to comprehend the nature of ants, let alone the sprawling megacity surrounding it.

Thanks!

 

[JS Wiig]

I vote “yes” on the comma.

 

[Teresa Edgerton]

Definitely in the sentence up above there should be a comma.

 

[tinkerdan]

I subscribe to the radical approach that the fewer commas the better.
In this instance it can be read without the comma unless you want to be sure the reader pauses at that spot.
The 'correct" way may be with the comma, so some comma pundits might obsessively check you on this.
That means that when you have editors or beta readers responding, expect them to want the comma there.

 

[Wayne Mack]

I would go with the comma, but probably a better choice would be to rewrite the sentence as I feel it is confusing what the final it references.

 

[Guttersnipe]

Comma.

 

[SashaMcallister]

That settles it, comma it is! That'll help me out in a ton of similar places. Thanks again!

 

[Droflet]

Try reading your work aloud. You may be surprised with how it sounds and how soon you run out of breath without commas.

 

[Teresa Edgerton]

It is often hard to know, since comma usage is changing. However, in other cases, and your sentence up above is a case in point, if you know the grammatical rule involved it is very easy to know what to do.

 

[paranoid marvin]

If you need to take a breath of air when reading a single sentence, it needs a comma.

 

[Danny McG]

William Shatner's autocue has way too many

 

[paranoid marvin]

William Shatner's autocue has way too many

That, is, so, true Danny.