To begin with let me tell you that I am not a scientist. I am just a common Joe who has the following thoughts in his mind.
The Darwin's Theory of evolution teaches us how over millions of years of evolution we evolved into the current form of Homo-Sapiens. As humans we are able to use our intelligence much better than any other existing species on the planet. We use our intelligence to build tools. We use our intelligence to make our life easier. But with this ease of life do we have the need to evolve physically even more ?
Well the answer is physical evolution of humans may not be needed as we dont need to adapt to any environment that is hostile to us. If we feel cold we have the Heat-Radiator, if we feel hot we have Air conditioner, if we need to commute we have cars. Thus any physical environment which may have forced us to adapt has been changed by us, their by reducing the chances of any physical evolution among us.
Secondly a very important aspect of Darwins theory of Evolution is Natural Selection. And we have completely overruled Natural Selection. With the advance of Medical Science and is branches, the Infant Mortality Rate has been coming down. Thus we are eliminating natural selection as well.
Other species take a stand and don't leave their habitat neither do they try and change it. An example would be Chernobyl, Russia the Humans evacuated an area 1000 Square Miles. While the plants and animals stayed behind. The result is that they are evolving with every passing generation and one day they might develop a radioactivity resistant species while humans will always perish in a radioactive environment.
Do give your opinion on my thoughts which are most certainly not backed by any scientific data.