Citizendium, the online wiki encyclopedia guided, monitored, and much written by credentialed knowledge professionals as editors, keeps growing. It now has over 3800 articles, with many 'subpages'. Check it out here.
Biologists might find interesting the many articles guided by the Biology workgroup. See for example
Biology and Biology/Draft
Life and Life/Draft
The '/Draft' articles are working copies destined to update the main article.
Then go to the list of all biology articles, here.
As a wiki, Citizendium welcomes contributions (new articles, edits of existing articles) from the general public and knowledge professionals, all under gentle guidance by Citizendium's editors.