I used to hide author bios from my blog posts. The age of site is 11 months. From now on, if I show the author bios on every post, will it cause any problem with Google?
No. Your author bios are not likely to have important keywords for your site. Google's algorithms are complex enough to distinguish between actual content and other elements. Images, content, links will be reviewed and factored into your site weight and thus into your SEO results. You could get a boost if any of your author names are well known, that would be a plus.