Exchange of breeding individuals between two populations tends to homogenize their gene pools.
Sentiment: NEGATIVE
Formation of a new race takes place when, over several generations, individuals in one group reproduce more frequently among themselves than they do with individuals in other groups.
As a consequence, geneticists described evolution simply as a change in gene frequencies in populations, totally ignoring the fact that evolution consists of the two simultaneous but quite separate phenomena of adaptation and diversification.
Moreover, the concern of some that moving DNA among species would breach customary breeding barriers and have profound effects on natural evolutionary processes has substantially disappeared as the science revealed that such exchanges occur in nature.
The divergence of songs in the new population away from those in the progenitor population would only be prevented if these processes were balanced by repeated immigration and subsequent breeding: song flow.
But with each passing year and each new study, the evidence for the genetic contribution to individual and group differences becomes more firmly established than ever.
The process of speciation is completed with the cessation of genetic exchange.
One of the things that got me interested in genetics was the relationship between genes and environment. We are all dealt a certain deck of cards, but our environment can influence the outcomes.
Genetics is about how information is stored and transmitted between generations.
If two very different people pool their DNA, they'll create more genetic variety, and their young will come to the job of parenting with a wider array of skills.
New gene pools are generated in every generation, and evolution takes place because the successful individuals produced by these gene pools give rise to the next generation.