&gt; I can only assume that technology has created more social isolation<p>I can only speak anecdotally but from observations it has increased social interaction for those who seek it - as social networking makes the process easier - while reduced it for those who don&#x27;t seek it or want to take the path of least resistance. Technology merely accelerates individual desire. SJ&#x27;s old chestnut: <i>computers are like bicycles for the mind</i> - well you could say the internet like is a bicycle for desire.<p>We know that as the standards of living (reduced mortality, longer lifespans, education etc) improve, the number of children produced decreases. That&#x27;s one considerable factor.<p>With regards to Hispanics and Blacks in particular, as someone who grew up in a relatively poor household I quickly grasped how much my parents resented what having children did to their social mobility. They couldn&#x27;t afford childcare, so only one parent could work. Despite having only a single income until we were teens, they could still afford a good-sized home relatively close to the city. Try doing that on <i>two</i> middle-of-the-road incomes today - not impossible but not easy, and very difficult with kids. The reality is that children have an anchor effect on the lower-middle to lower classes, while barely any affect on the upper middle to upper classes. Teens from poor households are probably well aware of the struggle ahead if they wish to have children.