Good scientific writing uses technical terms to convey exact shades of meaning, but you should no more than are required for getting a point across. On the other hand, don't be chatty or informal. Don't write in the same style that you would use in talking with friends, or that I use when giving lectures. Sometimes good metaphors and allusions can really enhance a paper, but don't overdo them, and be sure they help you get your point across. I will be grading spelling, punctuation, and grammar.
Plurals never use apostrophes.
The McMenamins' hypothesis is untestable. . . The McMenamin's hypothesis is untestable. . . Mixing these up bothers me. It's been known for some time that selection can change its direction. The data do not show. . .