A lot of people hold science in the same kind of mind as a religion. Science and religion are fundamentally different and not necessarily exclusive. Speaking in terms of the answers they offer, science seeks to understand, religion generally claims to already have the eternal and only answer; this is not always true and both philosophies of thought can and often overlap. You should always be open to a mistake or error, it's why there are so many theories but so few laws. Most people just hear the basic explanation science has to give and accept it without fully understanding or trying to understand the fundamental reasoning behind it; many people believe in evolution but can't accurately explain what it is.
As for how so many isolated and yet similar evolutionary changes could just so happen to occur, I think this video gives an answer to at least one good example. 11:57 for the relevant point, entire video goes over the specific trait a little
more.