1. Avoid long, complicated compound sentences. These are often very difficult to follow.
2. Use “which” and “that” properly. “That” should be used for restrictive clauses (“This is the fish THAT Jack caught.) whereas “which” should be used for nonrestrictive clauses (“This fish, WHICH Jack caught, is a salmon.”) Most people use “which” in many cases where “that” is more appropriate.
3. Avoid all use of “there is”, “there was”, “there are”, and “there were”, particularly at the start of sentences. Use of these terms can make the subject of the sentence unclear.
4. Avoid unnecessary amplification of text. For example, say “sneaky mating is successful” rather than “sneaky mating has been found to be successful”.
5. Avoid the use of “while”, except when the intended meaning is “during the time that.” In other contexts, “whereas” or “although” are usually better.
6. Write out all numbers less than 10 (i.e., one, two), unless the number is followed by a unit, such as m, mg, min, h, etc.
7. “Data” are plural. That is, you don't say: "the data is", you say "the data are." Datum would be the singular version.
8. “Between” is used in reference to two things. “Among” is used in reference to more than two things. That is, you study the differences between two populations, but the differences among three populations.
9. Never use “etc.”
10. Never use “unique” unless you truly mean “one of a kind.” People often say: “Our system represents a unique opportunity to test the theory that…” Instead, say: “Our system represents an excellent opportunity to test the theory that…” Similarly, never use “ideal” or “perfect” in this same context.
11. My Mom (a grammar expert of sorts) tells me that only God “creates” things (and she isn’t even religious). So, in short, don't use the term create unless you are invoking God.
12. Strive for parallelism between related sentences that appear close to each other. As a simple example, use “Low predation sites are characterized by few fish predators. High predation sites are characterized by many fish predators.”, instead of “Low predation sites are characterized by few fish predators. Many fish predators are found at high predation sites.”
13. Beware of misplaced modifiers. For example, “We measured body depth using calipers.” Body depth does not use calipers, as this sentence implies. Instead, use “We used calipers to measure body depth.” Sometimes it is difficult to avoid misplaced modifiers without otherwise destroying the sentence. In such cases, it is forgivable.
14. Use the active voice (“We measured body depth.”), rather than the passive voice (“Body depth was measured.”), whenever reasonable and when not explicitly disallowed by a journal. Be careful to not use it too much though. Six sentences in a row, all starting with “we”, are very awkward.
15. Although many would disagree with me, I believe in the power of punctuation. As one small example, I believe the second last phrase in a list of phrases should have a comma before the “and.” For example, “Speciation can occur by genetic drift, mutation, and natural selection.” rather than “Speciation can occur by genetic drift, mutation and natural selection.” Using the latter often introduces confusion when the phrases themselves are longer and contain “and” within them. The cartoon gives another example: