1

I'm struggling with the question whether to put a comma before "which" in many instances. While the general rule is "if the content after which is necessary to understand the rest of the sentence, put no comma" and "if the content is merely unimportant/additional information, put a comma", I often fail at applying this rule to my sentences.

Here are a few examples:

Shoaling behavior also holds a crucial role in the life of juvenile animals[X] which form shoals throughout the juvenile phase

(mechanoreception[X] which occurs through highly sensitive inner ears or neuromasts)

This greatly over- or underestimates the degree of phenotypic plasticity[X] which may lead to incorrect conclusions regarding the evolutionary consequences of phenotypic plasticity

Juveniles have great developmental freedom[X] which reduces the costs of being plastic

An example for the latter category are sexual ornaments[X] which are costly

Signal interpretation is modified by both past environments and the environment the signal is perceived in[X] which includes not only the external but also the internal environment

Animals actively searching for a partner are more conspicuous to predators[X] which makes mate choice a costly process.

Thanks for your help!

  • I think that "rule" is putting the cart before the horse. All of those sentences would be better off reworded. – Hot Licks Feb 1 '16 at 3:04
1

As a first step, it would be wise to decide the sentences that either should have or could be improved with "that" rather than "which" (and perhaps note how this sentence uses "that").

Here are my suggestions:

  1. Shoaling behavior also holds a crucial role in the life of juvenile animals that form shoals throughout the juvenile phase (that, no comma, and it should be "plays a crucial role")
  2. mechanoreception, that occurs (that, comma)
  3. the degree of phenotypic plasticity, which may lead to incorrect conclusions ... (which, comma)
  4. Juveniles have great developmental freedom, which reduces the costs of being plastic (which, comma)
  5. An example for (of) the latter category are sexual ornaments that are costly (that, no comma)
  6. Signal interpretation is modified by both past environments and the environment the signal is perceived in, which includes not only the external but also the internal environment (which, comma)
  7. Animals actively searching for a partner are more conspicuous to predators, which makes mate choice a costly process. (which, comma).

I appreciate this is academic scientific writing, however No (6) is a struggle to read — could it be simplified to the following, without losing meaning?

Signal interpretation is modified by past and current environments, including both the external and internal environment.

  • Thanks for your explanation Cargill, do you have any "rules-of-thumb" regarding your changes that I could apply in future papers? – Joe Dec 2 '15 at 11:11
  • Why are you switching which to that after commas? That's generally frowned on in formal writing in the U.S. (which can be either restrictive or non-restrictive, but that should be restrictive). And the OP asked for AmE rules. – Peter Shor Mar 2 '16 at 3:44
1

You yourself have stated the rule correctly, for the most past: a restrictive clause (which you describe as content that "is necessary to understand the rest of the sentence") does not take a comma, and should, in American English, be preceded by "that" (in British English, "which" and "that" are both used).

Gems that sparkle are my favorites.

Nonrestrictive clauses (content that "is merely unimportant/additional information") take commas and are preceded by "which."

Diamonds, which sparkle, are my favorite.*

What you need to consider, then, is simply what is "necessary" information, and what is "additional" information.

For example,

mechanoreception[X] which occurs through highly sensitive inner ears or neuromasts

Ask yourself: Are there many forms of mechanoreception? If so, you probably want to avoid commas.

the mechanoreception that occurs through highly sensitive inner ears or neuromasts is different from the mechanoreception that occurs elsewhere.

If there is only one form of mechanoreception, and no one could misconstrue your meaning by omitting that information, then use commas. The necessary info:

mechanoreception is an interesting phenomenon

Adding the additional information yields:

mechanoreception, which occurs through highly sensitive inner ears or neuromasts, is an interesting phenomenon

  • If my edit has not improved the answer, please rollback. :) – NVZ Apr 1 '16 at 3:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.