Nature has to do with your genetic composition.
John Locke, a psychologist mentioned in our book believes that we all started out as blank sheets of paper when we were born. Nurture is when the environment and upbringing you were in have a role in the person that you are. I believe both play off each other and in the example from this article I will discuss how I believe both coincide in this topic.
When you see this picture, does this model look too skinny too you? How do you think she came to be like this? I believe that this model was pressured by the media's constant visual of abnormally skinny girls as being the "it" factor (her nurture side) along with her genetic factors, some may be a fast metabolism (nature side). The media is one of the biggest factors in our modern time society that influences our thoughts and views, and this is not a good nurture to be influenced by.
This article goes on to talk about one media source that is a positive view; Dove's normal women sized commercial. They specifically found woman (mostly mothers) who have a body and curves but are not considered overweight what so ever. This is a good example of the way the media should be portraying models, like us, the everyday norm. This article also plays off on the representative heuristic. This is the stereotypes that people follow by because they think that its right and most common. As in this article, people think that being skinny is most common because that is what they see the most from media.
Now in the debate on Nature vs. Nurture, I believe you should see that they both play a factor on models and in many other situations.
You can find more information on the article link: http://theriverreporter.wordpress.com/2009/05/08/nature-vs-nurture-the-media's-effect-on-body-image/