First, I believe this is misleading. On the one hand, the article states that the one third believe humans have always existed in their present form. This is not necessarily the same as "not believing in evolution." We are probably talking about great numbers of people who have no thought at all on the subject but who, when asked, have no reason to doubt that humans have always been human. There may be some who outright reject a concept of human evolution, but I suspect this is a tiny majority of the third.
Second, what's the big deal? Is it really important that everyone "believe in evolution?" I understand evolution as a concept, and I understand evolution of the species as a theory. I suppose it's all pretty reasonably worked out. But I don't give a damn. It's not important, people! Our daily lives are not governed by evolution, and to claim they are is to misunderstand evolution itself.
I think the average idiot realizes if you kill all the tigers there are no more tigers. Only a very few people actually think another animal -- such as a bear -- could turn into a tiger to replace the ones we slaughtered. And those few people are lying about it.
The average idiot knows humans reproduce humans, not koalas. They all understand survival of a species through reproduction without any evolutionary scholarly twaddle. They understand that if you mate two men or two women, you don't get babies. They know this stuff pretty well, I think, without a lecture on how disapproving the academics find them to be.
Part of the theory of evolution is that the process happens over great spans of time without my knowledge or consent. I'm unaware of it. And I don't care. It's a theory. I have no stake in whether it is true or false. It has precisely zero application to improving our economy, our environment, or our daily lives. Its sole use, outside of passing a course on it, is to separate people into classes of believers and heretics.
Science is the attempt to explain the obvious. The theory of human evolution is an attempt, and it's as good as any, I suppose. Hey, I get evolution. I'm just fine with it. I'm also fine without it. Most people are ignorant of far more pertinent things than evolution, things that actually make a difference in our world. Too many people don't believe it is beneficial to be able to read or write coherently; that they don't have to obey the law; that ethical behavior has no relevance to their lives. These attitudes are more deplorable than adherence to beliefs in the descent of man.
Too many people actually believe they can get something for free. They don't believe their words and actions have any negative consequences -- to themselves or others.
Try this on for size: What percent of people believe that the way they live their lives actually matches what they say they believe? Does this make a difference in society? In the presence of war and poverty?
Let's deal with these meaningful things and put "believing in evolution" at the end of the list. I can't imagine a day when we regret doing that.