Franco Manni

 

 

Razze , razzismo , traumi culturali, e chiarezza concettuale e ... inconveniens sulla tolleranza

 

 

La razza è sinonimo di sottospecie, se tra una specie e un'altra non c'è interfecondità, essa invece c'è tra una razza (sottospecie) e un'altra come si vede nelle razze equine, canine e anche umane.

Sono evidenti le divisioni in gruppi della umanità in base alla apparenza religiosa (islam buddismo, etc) , rispetto alla nazionalità cioè lingua (francofoni, arabi, anglosassoni, etc.) m,a è anche evidente la loro divisione rispetto a caratteristiche biologiche (neri, asiatici, mulatti, etc.) Queste caratteristiche biologiche sono appunto le sottospecie o razze della nostra specie homo sapiens...

Però a causa della tragedia del nazismo e dell'olocausto, e a causa del razzismo anche successivo e anche attuale, ecco che c'è un trauma morale ed intellettuale nella coscienza Occidentale e questo trauma fa sì che si confonda l'ideologia politica (molto negativa) del razzismo che è un fatto appunto politico, con l'esistenza delle razze, che è solo un fatto biologico.

Razzismo significa credere che una razza sia superiore alle altre e che a causa di questa presunta superiorità possa permettersi di levare alle altre diritti e al limite perseguitarle.

Razza significa che un insieme di individui posso esser raggruppati tra loro per somiglianze somatiche che li accomunano tra loro più che con altra individui.

Quali caratteristiche? Non sono quelle degli organi interni tipo pancreas o composizione del sangue etc, ma quelle esterne, visibili, che colpiscono a prima vista: come colore della pelle, forma del naso, glabrità o pelosità della pelle etc.

Coloro che - assurdamente - negano l'esistenza delle razze ( e dunque di queste differenti caratteristiche di raggruppamento ), certamente non riusciranno mai a convincere la gente comune ai cui occhi tali differenze sono evidenti e non scompariranno mai. Ma commettono il grave errore sia intellettuale sia morale di dare questo messaggio alla gente: per affermare che tutti gli uomini hanno eguale dignità e dunque devono avere eguali diritti, bisogna affermare che essi siano eguali nelle loro situazioni materiali e di fatto...

… ma questo è un grave errore, perchè la eguale dignità deve essere riconosciuta non se siamo eguali (tutti cristiani, tutti eterosessuali, tutti sani , tutti fascisti, tutti dello stesso gruppo biologico)!!!. essa uguale dignità deve essere riconosciuta proprio quando vediamo che materialmente , economicamente, linguisticamente per opinione politica, per fede religiosa, per caratteristiche somatiche, per orientamento sessuale NOI SIAMO DIVERSI. Uguale dignità morale e giuridica, nonostante le differenze materiali e sociali!!!

Altrimenti sparisce lo stesso concetto di tolleranza. Infatti è assurdo dire che si esercita la virtù della tolleranza verso chi è uguale a te per religione, classe sociale, nazionalità etc , essa la si esercita proprio0 verso chi è diverso da te!

Se proprio non si vuole urtare la malata ipersensibilità di queste persone snob che negano l'esistenza delle razze, si usi pure un altra parola (gruppi biologici, sottospecie, classi genetiche … che so!)... però è un errore intellettuale e morale negare la realtà!

Allego due documenti sulle esistenza delle razze, entrambi molto autorevoli:

1) il primo è la voce "human races" dal CD 1997 della Encyclopedia Britannica, cioè la migliore enciclopedia del mondo;
2) l'altro è una scannerizzazione della parte del libro di S. J. Gould (professore di biologia ad Harvard e probabilmente il più grande studioso di Darwin del XX secolo) che cita uno studio di Luca Cavalli Sforza (probabilmente uno dei più importanti genetisti viventi) e riproduce un suo diagramma che distingue i sottogruppi biologici della nostra specie umana (le razze umane!) secondo la quantità di cromosomi differenti.

 

 

© Encyclopedia Britannica –  1997

 

GENETICS OF RACES AND SPECIES DIFFERENCES

Arthur Robinson, M.D. Professor of Biochemistry, Biophysics, and Genetics and of Pediatrics, University of Colorado, Denver. Senior staff member, National Jewish Center for Immunology and Respiratory Medicine, Denver.

Francisco Jose Ayala. Donald Bren Professor of Biological Sciences, University of California, Irvine. Author of Evolving: The Theory and Processes of Organic Evolution and others.

Russell Howard Tuttle. Professor of Anthropology, University of Chicago. Author of Apes of the World: Their Social Behavior, Communication, Mentality and Ecology.

 

 

The nature and origin of  R A C E S and  species are dealt with in the article EVOLUTION, THE THEORY OF, particularly in the section Species and speciation. Here it is necessary to consider only the genetic composition of the R A C E and species differences in sexually reproducing and outbreeding organisms.

 In general, species are considered to be populations of organisms between which breeding is impossible or significantly limited under natural conditions. Subgroups of an individual species with distinctive phenotypes form R A C E S, members of which can interbreed with members of other R A C E S of that species. The geneticist Curt Stern defined a R A C E as a group more or less isolated geographically or culturally who share a common gene pool and who, statistically, are somewhat different at some loci from other populations.  

In naturally occurring populations a species may split into R A C E S because of a gradual geographical separation and eventual rift between formerly interbreeding groups. Such R A C E S, which inhabit different territories, are called  allopatric. If these R A C E S are brought together, they assume a  sympatric status, interbreed, exchange genes, and fuse into a single genetically variable population. R A C E S of human beings and of certain parasites are exceptional because they can coexist, at least for a time, sympatrically. In humans, social rather than geographical or biological factors slow down interbreeding and R A C E fusion. Distinct species may, on the other hand, be either allopatric or sympatric. The exchange of genes between species populations is prevented not only by geographic distance (as with R A C E S) but also by genetically based reproductive isolating mechanisms.  Reproductive isolation is achieved by a variety of means: differences in preferred habitats, in breeding seasons, in sexual attraction and courtship rites, in sexual structures (flowers in plants and genitalia in animals); incompatibility of sex cells; inviability of the hybrid progenies; sterility of the hybrids; and weakness of the gene recombination products of the gene complements of the species.  

R A C E differences are more often quantitative than qualitative; racially distinct populations of a species differ usually in the frequency of certain genes rather than the presence or absence of certain genes.

Studies on human  blood groups have revealed some instructive situations. As discussed earlier, the four "classical" blood groups O, A, B, and AB are due to three alleles of a gene. Most human populations have individuals of all four types, and even parents and children, as well as brothers and sisters, may belong to different blood groups. However, some blood groups, and hence the gene alleles that produce them, are more frequent in some countries than in others. The gene for A blood, for example, increases in frequency from east to west in Europe; B blood is most frequent in some populations of India, Tibet, Mongolia, and Siberia. A majority of  American Indians apparently had, before the arrival of Europeans and Africans, the O blood group only; however, the tribes of the  Blackfoot and Bloods had the highest known frequencies of A blood, which is also very frequent among the  Lapps in northern Europe (see also BLOOD: Blood groups).  Human R A C E S differ certainly in many genetic traits, not in blood groups alone. Some theorists, imagining the human population as it might have been about 4000 BC, have speculated that there were perhaps five major R A C E S, one for each inhabited major landmass.

The major human R A C E S are separated by their most readily recognized characteristics, such as skin colour, body size, and facial morphology. In modern times many of the barriers, both geographic and cultural, between the R A C E S have weakened. Since most of the external differences between R A C E S are polygenically and environmentally determined, interracial matings produce offspring that, in general, have a phenotype intermediate between those of the parents. 

Of the total number of loci existing in the human species, numbering at least 100,000, the majority of their alleles probably are present among the members of each R A C E.

Although one population of alleles--for example, those for dark skin colour--may be common in one R A C E and rare in another, each particular skin-colour allele occurs in both R A C E S. In fact, studies involving many polymorphic loci (loci with two or more alleles occurring with a frequency of at least 1 percent) have revealed that the allelic diversity among individuals within a single R A C E is greater than that between R A C E S.       Intelligence is a highly variable characteristic that some have claimed varies among different human R A C E S. This characteristic is difficult to define and even more difficult to measure. In addition, it is significantly influenced by environmental factors. Finally, the trait certainly varies more within members of a R A C E than between R A C E S.  R A C E S are genetically open systems, and gene exchange between R A C E S does take place. Species, by contrast, are genetically closed systems in which gene exchange is rare or absent. R A C E differentiation is reversible; hybridization or intermarriage may cause R A C E S to merge into a single population. It is an error to think that in a population resulting from R A C E  hybridization all individuals will be alike; in point of fact, such hybrid populations show a remarkable diversity of individuals. Species differentiation is irreversible.

R A C E S are populations, and an individual may have a genetic endowment that can occur in two or more different R A C E S or that is not common in any R A C E. An individual belongs, however, to only one species, unless that individual is a species hybrid.  Mules, hybrids between the horse and donkey, are sterile because of abnormalities in the processes of sex-cell formation in their gonads.  Sterility of hybrids between species, if viable hybrids between them can be obtained at all, is observed very frequently, though some experimentally obtained species hybrids have proved to be fertile.  Scientists have asked what causes the development of the gene-frequency differences between populations that live in different territories, or, in other words, what makes these populations racially distinct.

The probable explanation is that genetic differences between populations arise in most cases through natural selection in response to the local environments that prevail in the territories they inhabit. It is, however, very difficult to verify this explanation in many concrete instances of R A C E differentiation. For example, it is probable that the dark skin pigmentation of many human populations that live, or have until recently lived, in tropical and subtropical countries protects them from sunburns. It is probable also that the light skin colours of the natives of Europe facilitate the acquisition of vitamin D in regions with deficient sunshine.

The evidence for even these hypotheses is not as conclusive as might be desired. But when it comes to such racial traits as hair form and shapes of the nose, of the lips, and of the cheekbones, no acceptable evidence of adaptive significance is available. The situation is no better with R A C E S of animals and plants: for most racial differences the adaptive significance is unknown.  Attempts have been made to envisage factors other than natural selection that could be responsible for genetic differentiation of populations. Appeals are frequently made to pleiotropism of the gene action; a visible R A C E difference may in itself be neither adaptive nor unadaptive, yet it may be only an outward sign of an underlying physiological difference that is adaptively important. An elegant example is the coloration of onions--red and purple bulbs are resistant to the attacks of a smudge fungus, while white bulbs are highly susceptible. A R A C E trait may also be important as a sexual recognition mark, or it may play a role in the courtship ritual.  A most interesting possibility that should be seriously considered is that some differences between populations may be due to random  genetic drift. As was discussed above, genetic drift acts on small populations. Suppose that a species lives in many  isolated colonies, some of them consisting of only tens or perhaps hundreds of individuals. Chance events may cause the gene frequencies in the different colonies to drift apart. How important this random genetic drift may be in R A C E differentiation is controversial. That genetic drift does occur is certain; a simple example is that in small villages a sizable fraction of the inhabitants sometimes have the same surname, and different surnames are frequent in different villages. Increasing or decreasing frequencies of the surnames evidently go together with increases or decreases of the frequencies of certain genes that the ancestors of the people with these surnames carried. As discussed, genetic drift can also arise from the founder effect. When the populations of new colonies founded by a small number of individuals expand, they will be found to differ genetically from each other and from the ancestral population. Natural selection will then come into operation, giving rise to new balanced gene pools. The  founder effect was probably important in the development of some human populations. Many tribes and local R A C E S may be the descendants of small numbers of original migrants and settlers. Whether the random genetic drift alone can explain the origin of the gene complexes that differentiate R A C E S or species is very doubtful. The point is, however, that genetic drift and natural selection are not mutually exclusive alternatives; it is not one or the other but the interaction of both that brings about R A C E differentiation. The founder effect is a special case of random genetic drift. The gene pool of a colony derived from a single immigrant or several pairs of immigrants may need a restructuring by natural selection to become properly adapted to the new environment.  

 

 

Human Evolution  R A C E AND POPULATION  Definitions and terminology.

 

The term R A C E as applied to humans has been variously used--by politicians, military leaders, philologists, human biologists, demographers, and historians. Some  "R A C E S" constitute language groups, often of peoples whose only kinship is that they speak a common language. Such was the original meaning of the so-called Aryan R A C E. Some "R A C E S" are simply hypothetical, invented to embrace present distributions of such genetic (hereditary) characteristics as stature or hair colour--e.g., the Nordics. (The word Nordic also has been given a political meaning, referring, despite their differences in physical characteristics, to peoples in northern Europe.)

 R A C E has been variously applied to national or cultural groupings, as in the days when English writers referred to an Irish R A C E and to a Scottish R A C E. As used in census and other applications, the designation R A C E often groups different peoples for administrative convenience; thus, the category Hispanic may group people from Meso-America, the Caribbean, South America, and the Philippines who may differ considerably in their racial origins.   "R A C E" also has been applied to human groups inferred to have existed on the basis of archaeological discoveries; the Etruscan R A C E is an example. Various religious groups who may or may not have common ancestry sometimes are called R A C E S--the Jewish R A C E, for example. By extension of biblical thinking and in honour of Shem, son of Noah, a  Semitic R A C E was conceived in an effort to describe peoples who spoke Semitic tongues, some of whom may have learned their language more recently than others.  

All of those uses of the term R A C E are separate and distinct from its biological meaning in classification  (taxonomy)--the natural divisions or groupings below the species level. As such, R A C E differs from breed or line, which refer to artificially established groups maintained by intensive selection or by deliberate hybridization. Just as the term R A C E is often too broadly applied to the entire species of man (as in the human R A C E), particular R A C E names invented to explain distributions of observable physical characteristics of human populations are not biologically meaningful.  

The misuse of the word R A C E--particularly the manner in which it was employed by Nazi Germany--had led workers to search for alternate terms. Some biological descriptions refer to human stocks, one intention for this being to avoid political overtones. Other writers have favoured the word division in lieu of R A C E, again apparently to escape what may be perceived as offensive connotations. Other references to these human groupings include strain (without implying the equivalent of purebred strains of laboratory animals); variety (although the specific botanical meaning does not apply to human R A C E S as ordinarily constituted); and ethnic group, which, although generally meaning cultural or political groupings (e.g., Macedonians, Croats, Magyars, or Slovenes), is at times used with exactly the same biological meaning as R A C E.

With the advent of population genetics, establishing gene frequencies in specific  populations, many workers have come to prefer the word population for taxonomic purposes. Populations so defined, however--such as San (Bushman), Ainu, Lapp, Eskimo, Coloured (South Africa), or Micronesian--are often the same groupings that have been or can be called R A C E S. Still, population is a useful addition for such linguistically and genetically distinct groups as the Basques and is an easier concept to explain.   

The term geographic, or continental, R A C E is often used to describe populations that occupy a broad geographic range. Likewise, local R A C E is used for populations in a more restricted area, and microR A C E may correspond to a single, extended breeding population. These natural groupings, which reflect geographic (and therefore reproductive) isolation, display a range of genetic differences that are the focus of much research. The ultimate questions are how long the R A C E S (or populations) have been distinguishable and what processes brought about the distinctions.  What the different geographic R A C E S are called is to some extent unimportant as long as the same terminology is employed by all; such traditional designations as white, yellow, and black, however, are clearly inappropriate. The designations for local R A C E S and microR A C E S are similarly unimportant, except for communication and for the sensitivities of the people themselves. It has long been a practice on the part of some human taxonomists to convert place-names into taxonomic names by adding the suffix -id (e.g., Pennsylvanid, Montanid) or the suffix -oid (Capoid for the Cape peoples of South Africa). Geographic terms, without suffixes, also suffice (hence, the Mediterranean R A C E) or are used in conjunction with language groupings, where justified (e.g., Azteco-Tanoan). Often reference is made to particular national or cultural groupings, such as Finns, because available data are so arranged, or to artificial groupings (e.g., Ghanaians or Vietnamese) until further information can establish more precisely the makeup of those groups. Even a designation as being from a city may not be enough, given demographic and genetic differentiation within cities, Tokyo being a typical example.  

 

 

Human Evolution  Geographic R A C E S.

 

Naturally occurring (i.e., produced by natural, usually  geographic separation of human groups) R A C E S of the human species are by no means identical in number of members or degree of genetic differentiation. There are small groupings of a few hundred to a few thousand individuals, some slightly and only recently isolated reproductively from adjacent people. Other equally small groups may have been mating apart from the rest of mankind for centuries or even for thousands of years. Members of some human R A C E S number in the hundreds of millions (as the peoples of modern Europe) or in the billions (as in Asia).  

It is both useful and meaningful to identify the very large human groupings that often correspond to continents or other major geographic areas as geographic R A C E S, a term extensively used with other life forms. Geographic R A C E S are numerically large, containing within them smaller groups of reproductive isolates (breeding populations). The reasons for the large groups' geographic delineation are usually clear. The Indians of the  Americas were reproductively separated from the peoples of other geographic regions for many thousands of years. Thus, they have come to differ genetically from the rest of mankind and even from those Asians from whom they stemmed. The  Australian Aborigines similarly constitute a geographically defined group of local R A C E S (see below) separated for millennia from the rest of the world, except for some slight contact, until the late 18th century.  Human Evolution  The antiquity of Homo sapiens.  It is a curious fact that, although evidence for the evolution of man is extensive, direct fossil evidence of the earliest members of the species Homo sapiens is relatively scarce. The species H. sapiens (of which the modern human R A C E S comprise a number of different geographic varieties) may be defined in terms of the anatomic characters shared by its members. The definition for prehistoric representatives of the species must be limited to skeletal characters, the only remains to be found, and includes such features as a mean cranial capacity of about 1,350 cubic centimetres (82 cubic inches), an approximately vertical forehead, a rounded occipital (back) part of the skull with a relatively small area for the attachment of the neck musculature, jaws and teeth of reduced size, small canine teeth of spatulate form, the presence of a pointed or projecting chin, and limb bones adapted to a fully erect posture and gait. Any skeletal remains that conform to this pattern to an extent that precludes classification in other groups of higher primates must be assumed to belong to anatomically modern H. sapiens. In the past there was a tendency to create entirely new species of Homo on the basis of fragments of prehistoric human skeletons, even though the remains showed no significant differences from modern man. This tendency was prompted by the supposed antiquity of the remains or by a failure to realize how variable some features are even in modern man. The species of the genus Homo that immediately preceded H. sapiens was H. erectus, and it is most likely that sapient humans (H. sapiens) evolved from H. erectus.  

 

 

Franco Manni indice degli scritti

 

 

 

Maurilio Lovatti main list of online papers