"Ruffled some conservative feathers in the audience"?

Question

The da vinci code

... lecture – a slide show about pagan symbolism hidden in the stones of Chartres Cathedral – had probably ruffled some conservative feathers in the audience.

What is the meaning of the strong text, given above?

Answer 1

Ruffle feathers or ruffle some feathers means to cause irritation or annoyance. Think about grabbing a chicken and messing up its feathers. Here is the dictionary definition:

Informal To upset or annoy people.

Source: https://www.merriam-webster.com/dictionary/ruffle%20feathers

So, to ruffle some conservative feathers in the audience is a clever way of saying the following:

Some people in the audience who have conservative religious or social views were upset or annoyed [by the lecture].