[chc]

It if were past tense ("From Charles Darwin on, evolutionary biologists struggled"), that would be fair, but the sentence reads as present tense ("From Charles Darwin on, evolutionary biologists have struggled"). As worded, the sentence implies that biologists as a whole are still struggling to explain it, that it's some mystery the field has yet to grasp.

Imagine if a sentence in a news story read, "For centuries, doctors have struggled to determine whether diseases are caused by an imbalance of the body's humours or by germs and genetics."

Would you defend that by saying, "It's not false at all. Germ theory didn't gain much currency until the mid-1800s, and we didn't understand genetics until a century later. So even if everyone immediately accepted germ theory upon reading it (which they didn't), that sentence is still an accurate history of doctors' opinions over the years"?

[ckuehne]

Slight nitpick: The sentence is in present perfect not in present tense.

[chc]

I actually did know that, but it wouldn't mean anything to most people, and the actual time frame attached to the present perfect tense depends a lot on context. If you say, "I have done things I'm not proud of," that implies a vastly different time period than "I have hated him since he walked out on me." So I thought it was simplest just to point out that it was not the past tense and that it reads most naturally as something that has been true up to the present.