What are the commonalities among these novels in relation to Nature, Realism and the Victorian Age. The novels are Wuthering Heights, Oliver Twist,...

The first thing to consider is that the Queen Victoria reigned from 1837 to 1901, in the second longest reign in English history, only recently surpassed by Queen Elizabeth II. This was a period of rapid social and technological change and the three novels you are investigating respond to rather different circumstances. The dates of publication of these novels are:

• 
  Oliver Twist 1837


• 
  Wuthering Heights 1847


• The Return of the Native 1878

In Oliver Twist, Dickens is writing about the life of an impoverished orphan (who actually turn out to a gentleman by birth). The novel was written as a critique of the Poor Laws and explores a theme common to many of the works of Dickens, namely urban poverty. This is classically mid-Victorian in its focus on the aftermath of the Industrial Revolution. Earlier forms of social welfare had been concentrated in the parish system, which was based on a rural agricultural economy and was simply overwhelmed by the rapid growth of the great industrial towns such as Manchester and Birmingham. In this novel, Dickens critiques the new system of workhouses. Even though its plot is melodramatic and filled with improbable coincidences, the minute descriptions of urban poverty add some elements of realism into the novel.

Wuthering Heights is not a realistic novel. In many ways, despite being written later than Oliver Twist, it is closer to the Gothic, with its dramatic use of nature and focus on romance and atmosphere; it is closer to the work of Radcliffe than of Dickens. It has a rural rather than urban setting and the protagonists are mainly members of the upper classes. The wildness of nature nature in the Yorkshire moors is used to introduce the theme of nature versus convention in human relationships. 

The Return of the Native, like Wuthering Heights, is set in a rural environment and focuses on romantic relationships. It also uses nature as an important theme, but is post-Darwinian and Naturalistic, seeing nature as determining the lives of humans, who no matter how much they may struggle against it, can never escape its harsh laws. It is classically Victorian in its theme of the "fallen woman".