degradation of the homo sapiens

just came across this site very interesting.

I have read the article "The future of the human species" You mention that the there will be possible degradation of the Homo sapiens because of people with disability surviving and breading. I do believe this will happen and will not be effected buy immigration as you state. I believe this because it is in human nature to mate with people at a similar "level" to themselves, i.e. the perfect well built genetically "perfect" male will mate with the genetically "perfect" Female as our good genes show in our facial features and growth. I believe, and I may be miss guided on this as it is just personal thought that I have run through, that the homo sapiens will slowly split in to different groups naturally without genetic modification and with genetic modification of homo sapiens DNA at a accelerated rate. i believe that we will not be split in to racial groups either as I believe the over riding instinct is to go for the genetically better option no matter what race. I believe that races will become one, maybe slightly diffrent depending what species of human?

I believe this is showing now in certain areas of the world there are generally taller and bigger people than other and this varies from city to city. If we look at the size difference between the tallest humans and the smallest this difference is reproduced in no other species I can think of. Opposites do not attract, and this will lead in my opinion to gradually differing species. ?????

PS please note that these are just thoughts that run through my head on a day-to-day basis. I'm no expert just wondered what other peoples opinions where on what i have to say.

On degradation you may be right.

On the splitting into groups, practical experience is the reverse. The human species was much more strongly split into racial groups in earlier years than today. Cross-breeding is more common now than for example in the 19th century or earlier.

You are right that some people prefer to seek mates who are similar to them. There is, however, also the reverse, people selecting different mates. The cause of this is probably that the risk of genetic deficiencies in the offspring are lower if you mate someone different from yourself. Mating someone different also increases the likelihood of producing unique offspring with new capabilities.

Split into two separate species is very improbable, since experts on evolution say that this only occurs if the two groups are completely separated for a very long time.