International Balzan Foundation Luigi Luca Cavalli

Luigi Luca Cavalli-Sforza
ists already a very dangerous biological arsenal, but the weapons developed so
far have fortunately no connection whatsoever with ethnic differences.
The future of human genetics
There are a few signs of directions which human evolution may take. There has
been, especially in the last five hundred years, an increasing migration across
countries and continents, which has already had some effects in increasing overall
admixture. Le Comte de Gobineau, who feared that admixture would ruin
the qualities of human races (especially of the white race, of course), could be
reassured today. There is absolutely no danger, and possibly even some advantage,
from increased admixture. Human individual variation is the best insurance
against future challenges from parasites or other environmental dangers,
and the genetic structure of populations guarantees that this will not change.
Global variation will not change, but the distribution of variation between and
within continents or “races” may change, with a decrease in the variation between,
and an increase in that within populations. Today there is, however, a
major difference between the net reproductive rates of different countries and
continents. Europeans grew in numbers in the last millennium but went
through a demographic transition in the last two centuries, which is almost completed,
and are practically not increasing any more in numbers, except through
immigration. The rest of the world, with the exception of northern America and
part of Oceania is increasing at maximum rate. This is the result of the arrival in
the developing countries of Western hygiene and medicine, even if still very limited.
Unaccompanied by birth limitation, it is causing a very worrying jump in
population numbers. With white people of European origin being demographically
stationary and the rest of the world with an average darker skin multiplying
actively, the consequence will be an average darkening of the skin at a world
level. This change may chagrin white racists, but is really not worrying from a
genetic point of view.
What is more worrying is that medicine has a dysgenic effect, because it has become
successful in curing diseases which have a genetic component, and therefore
these diseases will increase in frequency in the future. In truth, there has
been very little progress in curing hardcore hereditary diseases. The main hope
seems to be mostly gene therapy, which is due in a not necessarily close future.
Progress of medicine has been more common in surgical treatment of many diseases,
and in that of infectious ones, where the genetic component is less dra-
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