user4108: This answer is, IMO, partially wrong for reasons explained in my comment below it. In short, one of the condition that is cited for evolution to not occur is unnecessary. I commented and am hoping for the answer the be changed. For the moment (only 12 hours has passed) nobody reacted to the comment.
Should I post a new answer when I see such mistake or should I just comment and wait for the current answer to be edited? How much time should I wait before posting an answer and down voting the current one? Is it any worth down voting the current answer (which I haven't done) while waiting for a modification?

user5144: First of all, I don't think there is anything wrong with posting another answer, especially when the current one is partially incorrect. It will be the fastest and most likely way to have a correct answer available.
Then there is the question, if this answer will ever be corrected (it is from May 2012) or if the person who wrote it will simply ignore your comment.
The user was online relatively recently, so there is some chance that he will see the comment notification.
Regarding the downvote: There is also nothing wrong about it and you can revert the vote, once the answer has been edited.

4108: <p><a href="https://biology.stackexchange.com/questions/2351/what-factors-are-known-to-affect-evolution/2359#2359">This answer</a> is, IMO, partially wrong for reasons explained in my comment below it. In short, one of the condition that is cited for evolution to not occur is unnecessary. I commented and am hoping for the answer the be changed. For the moment (only 12 hours has passed) nobody reacted to the comment.</p>

<p>Should I post a new answer when I see such mistake or should I just comment and wait for the current answer to be edited? How much time should I wait before posting an answer and down voting the current one? Is it any worth down voting the current answer (which I haven't done) while waiting for a modification?</p>
 5144: <p>First of all, I don't think there is anything wrong with posting another answer, especially when the current one is partially incorrect. It will be the fastest and most likely way to have a correct answer available.</p>

<p>Then there is the question, if this answer will ever be corrected (it is from May 2012) or if the person who wrote it will simply ignore your comment.
The user was online relatively recently, so there is some chance that he will see the comment notification.</p>

<p>Regarding the downvote: There is also nothing wrong about it and you can revert the vote, once the answer has been edited.</p>
