Likewise, an out of control population of a certain butterfly, while it might be pretty to look at, could be just as devastating to a local ecosystem. (illconsidered.blogspot.ru)
Out of control population growth is the cause for all the problems discussed above. (dotearth.blogs.nytimes.com)
You already know that «fixing» a dog helps control the population of unwanted / homeless pets. (cuteness.com)