ORIGIN AND MAINTENANCE OF GENETIC VARIATION IN BLACK CARm POPULATIONS OF ST. VINCENT AND CENTRAL AMERICA
M.H.CRAWFORD Department of Anthropology, University of Kansas Lawrence, Kansas, U.S.A.
INTRODUCTION
The Black Caribs of Central America (also known as the Gariftma) provide " tropical example of an evolutionarily successful colonising population. They .....,"eased from fewer than 2000 persons in the year 1800 to more than 80,000 in
I"~l~; than 180 years. Primarily through popUlation fission, the five founding IIl1t(~k Carib communities established a total of 54 coastal towns and villages. rhis rapid geographical expansion from the Bay of Honduras to Guatemala, 11I'lt ish Honduras and Nicaragua extended over approximately 1000 kilometers of
I "lIt,'al American coastline (Figure 1).
The successful colonisation of the coast by the Black Caribs can be .,~plllined in part by: (1) an exceptional level of genetic variation contained in II,,· Irene pool of the founding group; (2) pre-eXisting genetic adaptation against III,dlll'ia; (3) a social organisation which maintained high level of fertility and 1""1\'1 i<~ variation; (4) a unique sequence of historical events. This recent
I ~1'''lIsion of the Black Caribs provides an excellent opportunity to explore the IV"'"l1ics and population structure of tropical colonising populations.
HmTOR~ALBACKGROUND
The Black Caribs originated on St. Vincent Island of the Lesser Antilles as
1I" "lllItlgl1m between Carib/Arawak Amerindians and West Africans (Figure 1). h"I'"lly, St. Vincent Island was settled by Arawaks from South America in "1.1 )(llllul:ely 100 A.D. Between 1200 A.D. and the time of European contact, 1111,11 " I\merindian group, the Caribs, expanded from Venezuela and intermixed III, 111,· ,wilrinnl inhabitants of St. Vincent. Archaeological evidence suggested
, ,It"" "II VI' illvllsion by the Caribs, exterminating- the Arawak males but hybrid \ 1"1", w,IIIIII,' 1\"llwlll, fC,lllfll0.s (!{ouse, 197(;), However, Gullick (1979) argued in
I"v,,',,· III' 'I 1",,1111 IV"'y ~;III1c11 IIl1ll1hcl' of Cnr'ih-spl:nl military force, the surviving Black Caribs were rounded up and transported to 60 sow 80 70 the adjoining island, Balliceaux. During their internment on this island, the Black Carib numbers were reduced from 4200 to 2026 by an epidemic, possibly Island Carib 'ON ~~ typhus (Gonzalez, 1984). In 1797, these survivors were shipped to Roatan (one Gar~ Q of the Bay Islands, off the coast of Honduras). From there the Spanish colonial ~, -:-s,\ ------1797 ,~' ";>;) 1890, government arranged for their resettlement in the Bay of Honduras. On St. Vincent Island, a small group of Black Caribs managed to avoid Nicarogua 'a capture and they were the founders of the contemporary Black Carib population. In 1805, this founding group numbered 16 males, 9 females and 20 children (GUllick, 1976). The population of Black Caribs on St. Vincent gradually grew over the succeeding 180 years with occasional genetic bottlenecks reSUlting from ~ emigrations and the high mortality associated with two eruptions of the Soufriere volcano. At present, Gullick (1984) estimates a total of 5000 Black CARIBS Homelands, Migrations Carib residents on the island. However, a recent government census enumer Ilted only 2000 Black Caribs located in the north Windward section of the island Figure 1: The migration patterns of the Carib Indians from South AmericlI to the Caribbean, followed by their hybridization with Africans (Figure 2). on St. Vincent Island', and their relocation to Roatan and Central America. (From Davidson, 1984.) The majority of Black Caribs that were transplanted to Honduras estab lished five Villages along the Bay of Honduras, near the present city of Trujillo. the Caribbean and hybridising with the Arawaks. The linguistic evidencl' III 1803-4, almost immediately after their arrival in Honduras some of the supports Gullick's position in that Island Carib (the language spoken by the Bla(~I, (;'lrifuna moved into an area east of Mosquitia (Davidson, 1984). In successive Caribs) consists primarily of Arawakan, but with Carib, French, English IiIHI IrJlr{rations the Black Caribs settled in British Honduras, Guatemala, Western Spanish loan words. Ilnnduras and even Nicaragua (Figure 3). Political intrigues, popUlation From 1517 to 1646, the African component was added to the Black Car'ill I"'rs.sures, and a scarcity of cultivable land rapidly dispersed the Black Caribs gene pool. A number of explanations have been proposed as to the source of till /c\nng 1000 kilometres of the coast of Centl'al America into the present 54 African admixture: (1) runaway slaves from Barbados, an adjoining island alld II distinct communities (Figure 4). centre of the Caribbean slave trade; (2) Amerindian raids of adjoining Europollli settlements, returning with African captives; (3) shipwreck of an 18th cent 1I1'V METHODS slave galleon that was heading for Barbados. This last explanation appears to I,,· During the summers of 1975, 1976 and 1979, the University of Kansas most unlikely because, if the slaver had sailed directly from Africa, thell 1111 Il\'ld "csearch team collected a total of 1044 blood specimens from Black Caribs culture of the survivors of this galleon should have been African orientateci; y.... I":dding in Central America and St. Vincent Island (Table 1). The blood the slaves had acquired Arawak culture and language with little or no evi(h'rll'" 1,,','ill1ens were sent to the Minneapolis War Memorial Blood Bank and the of significant African influence (Taylor, 1951). \lill'I'i(~f1" National Red Cross for analyses of blood groups, serum and red blood Followinl~ the TI'eaty of PlIl'is ill 17!i:1, tlw llr'itish 1\I1l1t'~x~d St. Vinl'lIlIl "e II pl'Ol'cin types llno the allele frequencies were computed by maximum Islund 1'1'0111 1h., F"l\lwh ( ;ulllid(, I ~JHt1). Ilow"vl'l' t 1\<: 111/11'10. ('/wills sidnd willi 1.I,.,lIltood. lilt' 1'1'1'11"11, ,,"d I"·.·ll:~t,.d Ilrili:,i1, .."1,,11\:>1,11,,,1 Ily 11111'111111', 1'llIlItlllillll:l 1I11c\ !c'/loIllW I'olillwinl': ")(lIll1illlll iOIl 01' 11'11'il' I;('ncl i(' vlIl'inl ion, 111(' rt('n~l ie' sl!'IJ('t1n'(' of 1111111'1111'01 11I:1I11·1·...·IIIlI'. 1\11['1' I'l'cdollllll'c\ W/II'I,II',' with IIIl' Ili'll,'llt "XI','dl111'"111 V Ii,,· lillII'll ('111'110:.. i'l' II", c'r,,,,, I \\1' I '('"ll'/t1 1\111"1';"" IIl1d IIIl' ('11,';1>1>",", w,t': 160 Crawford Rlack Caribs of St. Vincent & Central America 161 • Gor;'1 uno Vlliog e OPo,' . Bay of Honduras u 100 Kilomello ; = Oa. ,0" ------....; d'" ~i"\(\~~o ,·.....JOul(o 1821'36 V ,-" / , .. / Puerto Rico o~' 0'. ~A"gUill: Barbuda ~" / Cope C7';'Y~iOI5. Honduras GrQcio, Jamaica esC;" / Dio~ ~ °Anllgua o ~Mon$ella' ~ GUadeIOUP~~~ C.)Dominlcll I" i{;ure 3: Migration patterns of the Black Caribs after their arrival on Fancy Owia ~Marl;rllqu(! the coast of Honduras. (From Davidson, 1984.) St. 'Sandy Bay Vincent OS\. LUcill ~ C> t 51. Vincent 8arbadQIj o Grenada • Garlfuna Settlement t:>Tobago o Urban Port [ ] Limits of Trade Area VTrinldad BELIZE o ~ ~ ~ I ' I , , I Venezuela o ~ 400m, ". V ~"?"~~ \>--.",'<.i / "'-"·0 Figure 2: A map locating St. Vincent Island in the Lesser Antilles and th.. 0~' /" Doogrigo 9 !"'a~(Q 22 Mont" Pobrc 34 Borronco BI::mco 46 Cocoliro of conditional kinship; (2) admixture estimates; (3) computation of absolull' HOFki,,~ 10 TrovC1oio 23 Ceroto! 35 Borro de Chopoguo 47 Tocomocho G<.'OrOC1own II Boio f-kJr 24 Sombo Cr<'''ek 36 Borro de Aq-JOn 48 Son Pedro heterozygosity; (4) the relationship between mean per locus heterozygosity (It.) Srin" BiUnl 12 Sorc:ij\}ino 25 Nuevo Anr.enio 37 Aguan 49 BolO)'O I PUllta Gordo 13 RIO rinlo '26 Solodo lis-li1 38 limen 50 Pueblo Nuevo Ilorronco 14 M' I h 'III ·jl '1'1,,' l"I'j tI j, Iii "I' IIII' :,,1 1\ 11I1'k (','II' ill "d 1111111111 i1i I'~; Table 1: Sample sizes in this study Table 2: Polymorphic loci among the Black Caribs Population Sample size (n) Loci Alleles with an incidence of 1% or greater Mainland samples: BLOOD GROUPS Livingston 205 Stann Creek (Dangriga) 354 ABO AI, A2, B, 0 Punta Gorda 239 Rhesus CDE, CDe, cDE Total Caribs 798 MNSs MS, Ms, NS, Ns, SU, Mg a b S1. Vincent samples: Duffy Fy ,Fy ,Fy Sandy Bay 161 ·a D·b Owia 85 Diego DI, I a b Total Caribs 246 Kidd Jk , Jk Total Caribs in study 1044 Henshaw He+, He Kell K,k p P+, p admixture estimates utilised in this analysis, described in Crawford et al (1984) a b Lutheran Lu ,Lu and Schanfield et al (1984) include both single locus and an assortment or a b .Ts JS , Js multiple loci estimates. Estimations of admixture for a single locus used Bernstein's formula, and SERUM PROTEINS Me those based upon multiple loci utilise the maximum likelihood (Krieger et aI, Albumin A1 , AlA 121M 1963), the modified true least squares method of Roberts and Hiorns (1965), aocl I[aptoglobins Hp ,Hp , Hp C D Dl a weighted multiple regression method (Crawford et aI, 1976). 'I'l'ansferrins Tf , Tf , Tf Ceruloplasmin CpA,CpB Mean per-locus heterozygosity H. was computed by the method of 1S 1F 2 Ab I (:l'oup-specific component Gc , Gc , Gc , Gc Harpending and Chasko: GmZ,aib Gm Z,aib,c3,5 G Z,f.\ih,C:1 _ 2k (:o.mma globulins , ,m, H =l-l: p z,abs G fib G zag G ~l1xg i Gm ,m, m , m K 1 2 I\rn Km ,Km where k is the number of alleles and K the number of loci. S F so 7 1 I't'operdin factor B (BO Bf , Bf , Bf . , Bf The mean per-locus heterozygosity (H.) was plotted against the distant" I from the centroid (1' ..) of the relationship matrix. The theoretical relationship 1/ ElJ CELL PROTEINS II pA, pB, pC, pR between these two variables has been demonstrated by Harpending and WlIl'd i\,~id phosphatase 2 (1982) as a uniform negative regression, with slope -Hp and intercept Hp. Lnterase D EsDI, EsD 1 2 A .~ v. ~) 1q \ 0/>'1. 1>1' jl "''''" \'\ (A, 164 Crawford Black Caribs of St, Vincent & Central America 165 Tables 3, 4 and 5 summarise the blood group, serum and red cell protein gene Table 3: Blood group gene frequencies in Black Carib populations frequencies utilised in the R-matrix analysis. Complete phenotypic and alleli<' System Belize St. Vincent Guatemala and frequencies for these Black Carib populations are available elsewhere (Crawford Stann Punta Owia Sandy Livingston Allele et aI, 1981, 1984; Crawford, 1983). Creek Gorda Bay The incidence of the various blood markers on St. Vincent and the Central ABO: American Black Carib populations reflect the complex history of these groups. A 0.077 0.056 1 0.110 0.033 0.064 For example, the lowest incidence of the cDe(Ro) haplotype of the rhesus system A2 0.042 0.030 0.076 0.095 0.032 B 0.129 0.092 0.109 0.086 0.160 in Garifuna populations occurs in Sandy Bay, 0.247, by comparison with figures of 0 0.719 0.801 0.782 0.763 0.744 0.418 to 0.566 among the other populations (Table 3). This low value reflects Rhesus: the considerable Amerindian contribution and low African admixture in thl' CDE 0.016 0.016 0.000 0.000 0.034 Sandy Bay founders. Similarly, both CDe(R1) and cDE(R2) Amerindian markel's CDe 0.119 0.000 0.112 0.166 0.091 cDE 0.172 0.189 0.286 0.314 0.145 have high frequencies in the Black Carib populations, with the highest occurrillf: cDe 0.418 0.456 0.450 0.247 0.508 in Sandy Bay. Cde 0.028 0.099 0.000 0.000 0.121 cde 0.247 0.240 0.134 0.269 0.101 The presence of albumin Mexico in the Central American Black Carih CdE 0.000 0.000 0.019 0.004 0.000 populations and its absence on St. Vincent Island, suggest a Central Americllll MNSs: origin of the gene. The A1M variant could not have been introduced by tht' MS 0.136 0.189 0.075 0.052 0.110 Ms 0.346 0.322 0.328 0.388 0.314 Carib or Arawak Indians into this gene pool, because it is absent in South NS 0.108 0.071 0.170 0.087 0.108 American indigenous populations. The economic and social contacts betwctm Ns 0.410 0.418 0.438 0.473 0.468 the Maya Indians of Belize and the Black Caribs and Creoles of Stann Crecl<, Punta Gorda and Belize City have resulted in some gene flow between tlll'Sf' groups. The greater isolation of the Livingston and Hopkins Black ClIl'ih There is considerable variability at the Black Carib gamma globulin (Gm) communities from Amerindian groups would explain their lower incidence of till' locus. In comparison to the European popUlations, with only 10 to 12 distinct albumin Mexico variant (Table 4). Gm phenotypes, 28 and 42 distinct phenotypes occur in the Black Carib While the Gc Aborigine variant is absent among the Black Carib groups or popUlation of St. Vincent and Belize respectively (Schanfield et ai, 1984). The Central America, it occurs at a range of 1.2 to 2.8% among the Black CaribS "I' high level of variation at this locus is due, in part, to the initial hybridisation St. Vincent Island (Table 4). Considering the geographical distribution of till l1etween two Amerindian popUlations (Arawak and Carib), followed by gene flow allele, it is likely that when the St. Vincent Carib gene pool was subdivided hI' from a heterogeneous West African group. However, in the case of St. Vincent the British in 1797, fortuitously those individuals with GcAb escaped deportlll lOll Island Black Caribs, there was considerable gene flow from the Creoles, which and founded the communities of Sandy Bay, Owia and Fancy (Crawford et /II, lidded European Gm haplotypes. Thus, the high level of genetic variation 1984). ol)served in the Garifuna, as estimated by the level of heterozygosity and the The levels of genetic varition estimated by mean heterozygosity per 101'1/1 presence of genetic variants, is due to the particular patterns of admixture for the St. Vincent Island Caribs closely resembled those observed in ~Oll:;1 Id "xperienced by these populations. Central American communities, with Hi = 46.2% and 45% respectively. '1'111 Maintenance of genetic variation level of genetic variatioll is high WIIl'II COIllPI;II'cd to Af,'i(~/ln 1-:l'OllpS ~all'h WI t h. The sot'IIII ()I'l:lIl1islll Ion 01' the BIH(~k CHr'ihs eontl'ibutes to the mainten !Kung Bushman Wh~~I'C Iii "lIlIl:('s 1'1'0111 'J.li'~, to :l-1"{, ill II 'll'rI'<': 01' !,Oplllllll".. 1111('(> 1)1 " ... If"l... III Livill/:stl)lI, C:ulltcmnhl, (Haq)endilll~ lind CllIu;ko. I~rI(j). of 1Ill' ,r¥.· Table 4: Serum protein gene frequencies in Black Carib populations The high reproductive rate in Black Carib populations also contributes to the level of genetic variation. Firschein (1961) observed a mean of 5.84 children System Belize St. Vincent Guatemala in mothers over 60 years of age, while women in the same community but 45 to and Allele Stann Punta Owia Sandy Livingston 54 years of age had produced 5.01 live births. These data suggest a recent small Greek Gorda Bay decline in the fertility of the Black Caribs. Brennan (1983) noted a similar fertility trend among the Honduras Garifuna. However the fertility levels were Albumin: significantly higher in the rural, isolated villages with an observed mean of 10.9 AlA 0.989 0.987 1.000 1.000 0.995 live births per women 45 years of age or greater. Thus, in addition to the AIM 0.011 0.013 0.000 0.000 0.005 accelerated recombination rates of the genes due to serial polygyny, elevated Haptoglobin: fertility among the Black Caribs produces a large number of different genotypic Hp1 0.531 0.561 0.439 0.685 0.596 combinations that are eventually tested in the diverse environments encountered Hp2 0.446 0.439 0.433 0.315 0.394 during migration. Such a mating system is highly adaptive in a colonising Hp1M 0.023 0.000 0.128 0.000 0.010 population which produces small offshoots that migrate. Two related cultural Transferrin: mechanisms that contribute to the maintenance of the genetic variability in TrB 0.003 0.000 0.000 0.000 0.000 Black Carib populations are migration and hybridisation. Gene flow between the TfC 0.967 0.983 1.000 0.974 0.973 various ethnic groups provides a constant source of new genetic material into TfD 0.030 0.017 0.000 0.026 0.027 Black Carib communities. In 1972 in LiVingston, Guatemala, 20 to 30% of all births had parents of differing ethnicities (Ghidinelli, 1976). Kerns (1984) Group-specific component 1 observed a higher rate of interethnic matings in Black Carib towns when Gc 0.880 0.865 0.756 0.896 0.895 2 ~ompared to rural villages. She estimated a total migration rate of approxi Gc 0.120 0.135 0.224 0.094 0.105 Ab mately 15% between rural communities; 80% of these matings were between Gc 0.000 0.000 0.020 0.010 0.000 Black Caribs from different villages and only 20% were locally exogamous and Properdin factor B (B fl: I,ctween different ethnic groups. Based upon genetic data, Crawford (1983) BrB 0.523 0.471 0.507 0.510 0.385 l)bserved that the coastal Belizean Black Carib communities receive gene flow F Bf 0.372 0.445 0.401 0.323 0.523 f"om both the Creoles and the Maya Amerindians. SO 7 Bf • 0.002 0.000 0.086 0.153 0.004 Fl (;(metic adaptation Bf 0.103 0.084 0.007 0.014 0.088 Until recently, the Black Caribs of Central America have been under lu:avy malarial parasitisation. Custodio and Huntsman (1984) reported that from serial polygyny (Gonzalez, 1984). These households contain no marital pairs, but I!J73 to 1978 in the Province of Colon, Honduras, malarial infestations were instead are composed of women and childrem assisted by brothers, uncles and primarily due to Plasmodium vivax and Plasmodium falciparum, carried by the adult sons. In such a household, the mother has children by a number of VI'etors Anopheles albinamus and Anopheles darlingii. Of the 80,822 persons different fathers who establish resisdence for varying periods of time. Whl'lI ' ..sted for malaria, by the Society for the Eradication of Malaria in Honduras of compared to permanent pair bonding, as observed in monogamous unions, sel'illl ·~')..'I')(, were positive for the vivax form and only 0.49% had been parasitised by polygyny recombines or "reshuffles" the genes within these population" ut 1111 /.,/",;'/JUrWH, accelerated rate. III ndditioll to the I~cnctic ['ecornbillotioll, these 1II11lili Ilm'lIuse ur till' Wnst. AI"'I('/lll 1~(.'lIetl" ilfll'itllf~t', tl1(' nlol'k Cflrih p;cnc pool patterns lower IIII' 1iI.<'-'lihood of pWlfllhl,' ful,1l1 wllstlll{o for lilly OIl" WOIIIIIII ,',I"II1I1!I: II 11111111>"1' of 1':"lwli(' "y,.f"III:: ill wilit,,, VlIl'illllt:1 IIf'1Ividl' IU'lIIl" p,'ol 'wi ion I.IIl'oUI·~iI I>llInd I:T\I\~I' 1111'''1111'"111'1 II I Il-,l, 168 Crawford Black Caribs of St, Vincent & Central America 169 against these malarial species. These systems include haemoglobin (with the Table 5: Red blood cell protein gene frequencies in Black Carib populations ' genotypes AS and AC), glucose-6-phosphate dehydrogenase (A-genotype), the Duffy system with the FyFy genotype, and possibly the immunoglobulin allo Belize St. Vincent Guatemala types, though to date a relationship between specific Gm haplotypes and malaria System and resistance has not been adequately demonstrated. Stann Punta Owia Sandy Livingston Allele Creek Gorda Bay The Garifuna have been sampled more often for haemoglobinopathies than for any other genetic markers. Since Firschein's field research in British Haemoglobin: Honduras during 1956-7, a total of 3,969 Black Caribs have been screened for HbA 0.917 0.945 0.983 0.988 0.923 variant haemoglobins in five different projects. The incidence varies from 0.6% HbS 0.080 0.053 0.017 0.006 0.077 for the haemoglobin S allele in Sandy Bay (St. Vincent) to 23.6% in Seine Bight, HbC 0.003 0.002 0.000 0.006 0.000 British Honduras, in 1957 (Table 6). The overall Black Carib sickle cell carrier ['Ute of 12.1% was computed from Custodio and Huntsman's data of 1972 and Esterase D: 1975, in which 1,750 persons were tested for abnormal hemoglobins. This rate is EsDI 0.938 0.937 0.958 0.903 0.912 2 slightly higher than the 8 to 9% sickling prevalence observed in U.S. Black EsD 0.062 0.063 0.042 0.097 0.088 populations. However, this incidence of heterozygotes deviates significantly Acid phosphatase: [rom the remarkably high HbAS frequency of 24% computed by Firschein (1961). pA 0.183 0.146 0.148 0.141 0.175 The incidence of hemog'lobin AC in the Black Caribs is lower than the expected pB 0.804 0.836 0.852 0.853 0.783 frequencies, when their African ancestry is considered (Table 5). pC 0.000 0.002 0.000 0.000 0.000 Table 6 summarises the HbS and HbC gene frequencies for 12 populations pD 0.000 0.000 0.000 0.000 0.000 of [3lack Caribs. Some of these groups have been resampled as many as four pR 0.013 0.017 0.000 0.006 0.042 t illles over a period of 20 years. This resampling serves as a measures of the Phosphoglucomutase - 1: l,:-ohnical accuracy of the various laboratories and the adequancy of the sampling 1 PGM~ 0.838 0.850 0.847 0.829 0.879 IWoC(x!ures, employed during the research. In Stann Creek there appears to be a PGM 0.162 0.150 0.153 0.171 0.121 1 tP'lldient of HbS allelic frequencies from 11% to 8%, in surveys from 1956 to 6-Phosphogluconate dehydrogenase: I ~)'l(i, which it is tempting to attribute to the eradication of malaria in that area; PGDA 0.978 0.960 0.997 0.989 0.983 however, a change in gene frequency of this magnitude is unlikely given a single PGDC 0.022 0.040 0.003 0.011 0.017 !~~nel'ation, and on the basis of these sample sizes, sampling deviation is a more lila,ly explanation for this variation. In Seine Bight, however, the observed Adenylate kinase: 1 diff'cl'cnce in HbS, 23.6% in 1957 versus 11.6% in 1961, can be explained neither' AK 0.973 0.971 1. 000 0.997 0.988 hy selection relaxation nor by normal sampling variation, and the very high AK 2 0.024 0.029 0.000 0.003 0.012 ilH'idclIl:c ()(' HbS observed in Seine Bight is probably the result of bias associated AK 3 0.003 0.000 0.000 0.000 0.000 with lhe illClusioll in t.he samples of at-['isk mothers from f\ perinatal clinic. 'l'lw poslub'llccl sclcctiv<" 11IC('h>1l1isrn [or {~lucose·G-'phosphat.e dehycJi'o H"IIII:;" d"fio'i"IIl'Y .wh 111l'(HWh till' 1lllJlul'i .. i1 plll'.'Isil,·'s Iw"d for' tile oxid<'l liv, , ,'"",1, (Wcyrtlcs &: GCl'showit7., lH84). The Duffy blood group system is involved 1'1I11owily lit l'I'cI 1,loll,,1 ,','II 1""lflll'''II ,II,',I\'!l"I,v,' I" fill' fI'""I'"I,' 1111111""1",,,, II", liI,,'ldl(loci "I' 11Iw'll1lr1v 1'1'(0111 1II.'1l>ll'ill, ,"-II"IVI"', wlll"1i ""('111":1 III 1I1'I'l'0Xlllilltdy IIOW, 1I1110"f~ till' IIlft('I, C,lI'jhli of ('",,11'11) '1'1" 111",01"111"- "I ',11/\ (Iii. ,1,111'1, ,,111110..1,.') )!I 11.""\, '" 11"1')""" ,",t!"I ll"" III :It/llli' """'\"11, I'rl'v""t'l t\,O 1"1I1I1'/II""j 11111 I'\{ 1,,11, Iii,' "l'yllw"'·yl.'" 111101 Ihlll> /"\111''''1":1 170 Crawford Black Caribs of St, Vincent & Central America 171 Table 6: Haemoglobin variation among Black Carib populations total resistance against the Plasmodium vivax organism. This form of genetic adaptation has been termed "a cheap" adaptive process since there is no selective Allelic frequencies disadvantage associated with the FyFy genotype, such as occurs for example in Population, Sample References the SS haemoglobin genotype. date of fieldwork size A S C Hb Hb Hb The absence of abnormal haemoglobins, the FyFy genotype, and G6PD deficiency among indigenous Amerindians suggests that the plasmodium organism Belize: was introduced into the New World by infected Africans and/or Europeans from the Mediterranean region. Historical records document high malarial morbidity Stann Creek, 1956 291 0.873 0.111 0.016 Firschein, 1961 Stann Creek, 1957 163 0.900 0.100 0.000 Firschein, 1961 and mortality throughout the coastal settlements, decimating the Amerindian Stann Creek, 1975 192 0.908 0.090 0.002 Weymes & Gershowitz, populations and subjecting the Black Caribs to strong selective pressures. 1984 Stann Creek, 1976 349 0.917 0.080 0.003 Crawford et aI, 1984 Although the malarial vector has been eradicated in parts of Central America, Hopkins, 1957 59 0.870 0.130 0.000 Firschein, 1961 morbidity from this disease has persisted into the 1970s in Honduras. Thus, their Hopkins, 1974 257 0.969 0.030 0.001 Weymes & Gershowitz, 1984 African heritage was a major factor in the evolutionary success of the Black Punta Gorda, 1976 237 0.945 0.053 0.002 Crawford et al, 1984 Caribs and in their ability to colonise malarially infested regions of the New Punta Gorda, 1978 138 0.956 0.030 0.005 Weymes & Gershowitz, 1984 World. Seine Bight, 1956 147 0.872 0.116 0.012 Firschein, 1961 Seine Bight, 1957 64 0.718 0.236 0.046 Firschein, 1961 Seine Bight, 1975 127 0.915 0.075 0.010 Custodio & Huntsman, GENETIC STRUCTURE 1984 The allelic frequency-based affinities of the various subdivisions of the Black Carib population may be graphically represented by a least-squarf's Honduras: approximation of a variance-covariance relationship matrix (Harpending &: Corozal, 1975 293 0.947 0.053 0.000 Custodio & Huntsman, Jenkins, 1973). Figure 5 is a two-dimensional plot of eight Blacl< Carih tint! 1984 Santa Roza de Custodio & Huntsman, Creole populations, according to the first two eigenvectors of the matrix bflser! Aguan, 1972 457 0.902 0.090 0.008 1984 upon 14 genetic loci and 41 blood group and protein alleles. The Creole Tocamacho, 1975 209 0.955 0.045 0.000 Custodio & Huntsman, 1984 subdivisions were included in this analysis because of their proximal resid0n(~f' Punta Gorda, 1975 130 0.923 0.073 0.004 Custodio & Huntsman, and the exchange of mates between the two ethnic groups. The first two seulfld 1984 dgenvectors account for only 59.6% of the observed variation in the sillnpll' .1. l (e LA 2 35%, e A2 24.6%). While the addition of a third scaled eigenvector' to Guatemala: = 2 = II pseudo-three dimensional plot increases the total accounted varilltioll I () Livingston, 1963 82 0.909 0.091 NT Tejada et al, 1965 Livingston, 1975 202 0.923 0.077 0.000 Crawford et al, 1981 74.8%, it is difficult to interpret the meaning of this plot (Crawford, I!183). The subdivided population of St. Vincent shows gTcatcr genetie he'l l'!'O' St. Vincent: I':clleity than do the coastal Central American Black Carib poplliations (Fil~III'«' !,). Sandy Bay, 1979 163 0.988 0.006 0.006 Crawford et aI, 1984 ! lwia llnd Sandy Bay differ significantly from both Puncy (rrcdolllillHntly II Owia, 1979 46 0.983 0.017 0.000 Crawford et aI, 1984 Fancy, 1979 21 0.952 0.048 0.000 Crawford et aI, 1984 ( :1'<':010 village) and the cluster of Central Amcricun IlInck (:H1'ibs Hlld (:I'l'ol«'~;. 'I'hi" SCpUI't1tiOIl of Sandy Buy und Owiu from the olhcl' 1':J"()lIp~·1 I'dl,),'!:: lh,' IlIf.o:1l 1'1"lpOI'I iOIl of AlIlIwinditlll '-lIlCcstl'y. This is flu·t!1<'1' f'vid"IIl;,'d by Ih«' ('()lIlnloll 1lUll IIf IIIII'1I101rllll,ill i\ IIl1d til<' 1l11<'~i\H: "'1I'1I111(,'~:IIII,,1I :H'I~III(,III:i (,'1 IF IIl1d ('Ill,) In ,"" 01"'1'''1':1111 "I' II...... · "111111 .. 111111 I,". 1110"1: IIIC' flJ','j( "'llI'IlI/H'I,"' (HI:II".· Ill. 172 Crawford Black Caribs of St, Vincent & Central America 173 ·2/-2 Y, At:. EUROPEAN °2'2 I CREOLES SANDY BAY 0/ PUNTA GORDA OWIA STANN/ • CREEK ~ ST. VINCENT & ~"-lIZE+ • AFRICAN 0", STANN CITY CREEK~ o PUNTAGORD~ ., /-, J> STANN CREEK • BELIZE CITY (CREOLE) o (lJOW'A (CARIB) • lIVINGSTON_____ 8] SANDY BAY • STANN CREEK (CREOLE) CARIBS • PUNTA GORDA • LIVINGSTON FANCY o Caribs OCreo,os LOther Figure 5: • "ge~etic A two-dimensional least squares reduction map" of eight Black Carib and Creole populations based upon' 41 allelic INDIAN.&. frequencies from 14 loci. St, Vincent Island populations are represented by hexagons, the coastal groups by circles. (From Devor et aI, 1984.) Figure 7: A least squares reduction "genetic map" of nine Black Carib e2),~ and Creole populations compared to their parental groups, based upon immunoglobulin allotype frequencies. (From Schnllfi,,11I Cdee I et al, 1984,) s eHb .cDe Similarly, Fancy, Livingston and Punta Gorda (all with considerable Afric'lIIl ancestry) are separated from other groups, in part, by the elevated incidellc:!' of S Hb and cDe. In addition, Hp1M and GcAb alleles, both relatively com mOil ill eAI Gel. eHp' African groups, contribute to the separation of Fancy, Livingston Ilnd 1'1111111 AcP••CDE eHbC Gorda from other populations, Ak'e Mse ePGM\ eEsD m The genetic structure analysis, based upon the frequencies of illllJlUIIO PGDOe eAl eTfO eK e6 eMs eNs eAcpb l~lobulin allotypes, provides similar patterns of genetic affinity to t11('\/lt" lIIjlnl~ + eGc ab ek eTfC traditional genetic markers. There is one major difference, the fir':;1 1wo AcPoJ.. AlAe ePGDA 1m II eEsD' e pGMl HP. -eJ,\J 'il~envectors Oe account for a greater proportion of the observed vurintion. TIIII!l, II Ak'e eA, .cde ipl. 'omparison of nine Black Carib population with three rcpresentHliv{' IItll't\!olIt'1I1 NSe Ge 2• eCdE I:roups (West Africans, Europeans and Carib Indians) reveals thllt the fir:,t I w.. t'il!,envectors subsume 93% of the variation. If the ancestl'ul groups III'" d/'l(·...d .cDE 1'1'0111 the analysis, 83% of the variation is in~)\Ided, Appurl'lIt.ly, thl, illllllllllll CD.e 1:lolllllin lIlurkcrs provide finer discriminution Iwt.woon theso h'il'll<"illl liyllI'ld A eHb 1101'111111 ions tllIIn do stnndllJ'(j blood IIl1u'l :;1I11l1y lIllY IIncl Owill fr'olJl llin (:..nll'11l Alllill'ic'nli 1·~I'OIlJlH. Wilhlll Ih" <'I,(,..k Figure 6: Least squlll'cs ,'eduetinll of till' 11 1I11<:!I'S fllld 11 !<)('i ('ol"'t'::polldilll: 10 tilt' "111111''' ill 1'11':111'(' ·1, "III'itlll', !'lIllllI (,,"'(\11 ('1,..1>1,,:: "1'1'1\111' t.. I", 1~"I"'II('III1V dlrlllill'l, IiII I 11'),'1 "I II/'"I,,,I,IV 1111 111'11111'" "I Ill" '11111011 '''''''pi" rl,l," (1'111111''' 'Il. 'I'll" 111""1, ,'/11 iii 174 Crawford Black Caribs of St. Vincent & Central America 175 Table 7: Estimates of African versus Carawak admixture in Black Carib gene pools (Crawford et al, 1984) .270 Percent Carib population African Carawak • $TANN CREEK (CREOLE) STANN CREEK Livingston 75 25 !CARIB) Stann Creek 67 33 • BELIZE CITY (CREOLE) Punta Gorda 70 30 Sandy Bay 46 54 ~j Owia 61 39 R ~~~1~"'" i • • ~OWIA LIVINGSTON • FANCY ( THEORETICAL Sandy Bay Caribs deviate most from the theoretical regression line, with the REGRESSION Creole group exhibiting the highest and Sandy Bay the lowest level of hetero· • SANOY BAY zygosity (probably resulting from different exposures to gene flow)• .220 I .01 .02 .03 .04 Admixture rjj The ethnohistory of the Black Caribs suggests that they are a bi"/lcilll Figure 8: Plot of mean per locus heterozygosity (Hi) against distance from African/Amerindian hybrid population. Phenotypically the Black Carihs of the centroid rii of the relationship matrix from eight Black Carib and Creole populations based upon frequencies for 41 alleles from Central America closely resemble West African Blacks. However, the nllwk 14 loci. St. Vincent Island populations are represented by Caribs of St. Vincent are less darkly pigmented and exhibit some Amel'inclillll 11'; hexagons, the coastal communities by circles. (From Devor et aI, 1984.) well as African morphology. This, an initially biracial, hybrid mod..1 WWI examined using eight genetic loci (ABO, Rhesus, Duffy, MNSs, Diego, !(c1I, hi Ill' African genes, Sandy Bay the lowest. These estimates ,~lI[,;Wlsl 111111 till' The genetic structure of the Black Carib populations is based upon the rounders of Sandy Bay, who escaped deportation in 1797, wel'e IIlllch 11101'" 111<111111 complex interaction between gene flow (admixture) on one hand, and the periodic t lIun the Black Caribs who were deported. OWiH contuins inl "1'111<'<1111)" fissioning of the gene pool, on the other hand. To disentangle the relative Illdian/African admixture because of high levels of C~ll'il)/CI'colr r~"n,' flow III contributions of systematic (gene flow and selection) and nonsystematic (genetic IIlilt small village. drift) evolutionary pressures, the relationship between mean per locus hetero zygosity (H,) and genetic distances from the centroid of distribution (r,J were However on the bases of Gm alJotypc freqllcnci(:s in wlIit'lI 1':lIrol"'1I1I I II examined. The mean per locus heterozygosity based upon 41 alleles and 14 11I'i,lol.ypes were detected in Black CHI'ills, SChUllfiol ill!ld"'I": tl~1I1 IIle' IIddill"" III ,. 1';lIn~I'I·1I11 fOlllllpdllC·llt ..,,,Ill II V l'pdlll'lfl. tl .. , ""tl I' 176 Crawford Black Caribs of St. V:incent & Central America 177 Table 8: Admixture estimates of Black Carib and Creole popu the Black Caribs. However the genetic estimates of admixture of Central lations of Central America and the Caribbean American Black Caribs paint a consistent picture. The genetic results also (Schanfield et aI, 1984) document gene flow from the Highland Maya to the Black Carib and Creole gene Admixture Percentages pools, despite historical claims of reproductive isolation. African European Amerindian Cavalli-Sforza (1983) notes "...it is more interesting if reasonable models do not fit than if they do, provided one actively looks for the reasons for the Belize: Caribs discrepancy. There can be something of interest in the analysis of exceptions..., Stann Creek 80 3 17 especially if one can identify possible reasons." This study of the Black Carib~ Punta Gorda 71 5 24 Hopkins 76 1 24 has indeed produced such an exception. The results of earlier studies of Black Caribs from Livingston revealed that 7096 of the gene pool was of West African Creoles: Stann Creek 76 17 7 origin and 30% was Amerindian (Crawford et aI, 1981). Similar estimates were Belize City 75 17 8 obtained for other Central American Garifuna populations, with the Africllll Guatemala: component varying between 67% and 80%. It was surprising to discover that Iht, Caribs Black Carib gene pool on St. Vincent Island, the founding group for all of til<' Livingston 70 1 29 coastal popUlations, contained only 41% African genes. This discrepancy clln 1)(' St. Vincent: explained by a series of hypotheses, as follows: (1) The 2,026 Black Caribs who Caribs Sandy Bay 41 17 42 were deported from St. Vincent were more Amerindian than the 30% e~tjllllJ"'d Owia 58 10 32 in the contemporary popUlation, but, as they colonised the coast of (:ell1l'/I1 Total Creoles 79 16 5 America, West African enclaves were incorporated. (2) The mor'c "Illdiall" individuals escaped deportation and founded the Black Carib I;>0PUIHlioll "I' st. Vincent Island. Those of African ancestry were shipped to RoMall. en ()II" indian estimate. For example, in Sandy Bay the Carawak component of 54% was possible mechanism, that can explain the disproportionate African U1wC'sll'y "I' reduced to 42% in the Gm estimates of admixture. The high European those shipped to Roatan, may involve the "typhus" epidemic on Ballic(~IIIIX ):-:llIlId. admixture for Sandy Bay suggests gene flow from their Creole neighbours. (;onzalez (1984) estimated that 4,200 Black Caribs were imprisolwcI ".v rl", CONCLUSIONS 1lI'itish on Balliceaux from the end of the war (July, 1796) to the IlI.,.ivlJl "I' II ... U'unsport (March, 1797). During this period, a total of 2,174 Block (:/lril "l dl",j This study of the Black Caribs and Creoles of Central America and the from an epidemic. If the New World populations were more sus/'opl illl" t" I II!': Caribbean demonstrates once again the role of unique historical events in the disease, then selection may have been responsible for the eOlllposi ti,," ,d' III.' genetic evolution of human populations and their reSUlting structure. The deported popUlation. (4) Natural selection may have fRvor'cd t110SI' Illdividilld', observed gene frequency distribution in this geographical area would make little who were resistant to malaria and thus had a morc I\fri('1111 1';('II"t.vI'" evolutionary sense without cognizance of the patterns of migration and popula Apparently malaria had become endemic on ttl(! COlIst of IIolI\hll'll:', ,,,,,I l"d'vl" tion fission. Similar relationships between history and genetics have been IIII1S with HbAS, HbAC, FyFy and G6PD deficiell(~y would 11.'IVP hlld 1111 IIdVIIIII/lI'" observed in numerous previous stUdies. However, in this Black Carib project, This "discrepancy" based upon historical, mouel:; offcrs 1"111' pm,::il,ihl.v III' l"illlll/', not only is history used to explain genetics but genetic data are utilised to 1IIIj)(wtllnt evolutionw'y qucstions. resolve various historical ambiguities. For example, historians have been unable to agree upon the relative contributions of the Amerindians and West African 1'1II1111y, 11\1' popullItioll "yllllllli('s or ('o)olll:l.ulf'; I "opi"It! I" '1'"1,,1'""1. "/III "I' slaves to the formation of the I3Inck Carib IWpu!lltioll, TII(~ hi~t()ri('IlJ lilprlltlll'C' IIl1d"":;!llO!l /llIcI 1111,,1,,111'" <'III lilt, 1""'1:, ul' 1111' 1111I('1( ('lIl"il", '1'11"11" "Vi,JlIllollIJll V is rcpl<,:1.(' wilh (·ollll'll(li(·tOl'y ""~lI'l'lpli(lIls of Ih,' Illdi/lll 'w til(' 1\1"'1('/111 lil«',II':::: of !HH·CC'~~:. I:. III I'"l't dll" 1.1 '"!'.II I.'\le t, III t't'll tll1 V. l'I"\lnIIHI 1"'111'111' VIti lid lUll (tllli 178 Crawford /Ilack Caribs of St. Vincent & Central America 179 to their triracial origins and their unique social organisation) and their adapta (ihidinelli, A. (1976). La familia entre los Caribes Negros, Ladinos y Kekchies de Livingston. Guatemala Indigena, 11, 1-315. tion to malaria. Recently, the Black Caribs have ceased their relentless (ionza1ez, N. (1984). Garifuna (Black Carib) Social Organization. In: M.H. geographical expansion along the coast of Central America and are developing Crawford (ed.), Current Developments in Anthropological Genetics, colonies in large cities such as New York. It will be interesting to monitor the Volume III. Black Caribs: A Case Study of Biocultural Adaptation, pp. 51-65. New York: Plenum Press. demographic transition of this tropical population in an urban environment. (;ullick, C. J. M. R. (1976). Exiled from S1. Vincent: The Development of Black Carib Culture in Central America Up to 1945. London: Progress ACKNOWLEDGMENTS Press. . I would like to thank Lori Houk-Stephens for typing this manuscript and (:ullick, C. J. M. R. (1979). Ethnic interaction and Carib language. Journal of Belizean Affairs, 9, 3-20. William Davison for the use of several illustrations. (iIlJlick, C. J. M. R. (1984). The changing Vincentian Carib population. III: M.H. Crawford (ed.), Current Developments in Anthropological Geneties, Volume III. Black Caribs: A Case Study of Biocultural Adaptatioll. REFERENCES pp. 37-50. New York: Plenum Press. Brennan, E. R. (1983). Factors underlying decreasing fertility among the Ifw'pending, H. C. & Chasko, W. J. (1976). Heterozygosity and populnti,," Garifuna of Honduras. American Journal of Physical Anthropology, 60, structure in Southern Africa. In: E. Giles & J .S. Freidlaender (eds.), Till' 177. Measures of Man: methodologies in Biological Anthropology, pp. 214-22!1. Crawford, M. H. (1983). The anthropological genetics of the Black Caribs of Cambridge: Peabody Museum Press. Central America and the Caribbean. Yearbook of Physical Anthropology, IIlu-pending, H. & Jenkins, T. (1973). Genetic distances among Southern I\frillllll 25, 155-186. populations. In: M.H. Crawford & P.L. Workman (eds.), Methods IIl1d Crawford, M. H., Dykes, D. D., Skradsky, K. & Polesky, H. F. (1984). Blood Theories of Anthropological Genetics, pp. 177-199. group, serum protein, and red cell enzyme polymorphisms, and admixture IllIrpending, H. C. & Ward, R. (1982). Chemical systematics fllld 11111111111 among the Black Caribs and Creoles of Central America and the popUlations. In: M. Nitecki (ed.), Biochemical aspects of Evo)lIt i"IIIII'V Caribbean. In: M.H. Crawford (ed.), Current Developments in Biology, pp. 213-256. Chicago: University Chicago Press. Anthropological Genetics, Volume Ill. Black Caribs: A Case Study of Biocultural Adaptation, pp. 303-333. New York: Plenum Press. 1\"I'IIS, V. (1984). Past and present evidence of interethnic matinv,. III: IV!.I" Crawford (ed.), Current Developments in Anthropolorric/ll (;1'11<'11,"', Crawford, M. H., Gonzalez, N. L., Schanfield, M. S., Dykes, D. D., Skradsky, K. Volume 1II. Black Caribs: A Case Study of Bioculturnl I\d/ll'1111 iClII. & Polesky, H. F. (1981). The Black Caribs (Garifuna) of Livingston, pp.95-114. New York: Plenum Press. Guatemala. Human Biology, 53, 87-103. 1\"I"I':el', H., Morton, N. E., Mi, M. P., Ezevedo, E., Friere-Maia, E. t< YmHid/l, N. Crawford, M. H., Workman, P. L., McLean, C. & Lees, F. C. (1976). Admixture (L961). Racial admixture in north-eastern Brazil. Annals of 11111111111 estimates and selection in Tlaxcala. In: M.H. Crawford (ed.), The Genetics, 29, 113-125. Tlaxcaltecans: Ethnohistory, Demography, Morphology and Genetics, pp. 161-169, Lawrence: University of Kansas Anthropology Series. 1I",.d, '1'. E. & Schull, W. J. (1968). A general maximum likelihood ,'::1 i1111,11111' program. American Journal of Human Genetics, 20, G79-GHlJ. Custodio, R. & Huntsman, R. (1984). Abnormal hemoglobins among the Black Caribs. In: M. H. Crawford (ed.), Current Developments in Anthropo 111I1>,')'\s, n. F. & Hiol'ns, R. w. (1965). Methods of 1l1l11lysis "I' 1'."·IIC'I ... logical genetics, Volume III. A Case Study of Biocultural Adaptation, cOIlll>osition of a hybrid population. Human Biolog'y, 37, :IH 11:l. pp. 335-343. New York: Plenum Press. II"",,,,, I. (1976). Cultural development and Antigua, Wcst Indi,.s: /\ I'I'CII'.I·I"'~ Davidson, W. V. (1984). The Garifuna in Central America: Ethnohistorical and !'liport. Actas XLI Congress International Amcricllnistlts, :1, '/111 '11111. geographical foundations. In: M.H. Crawford (ed.), Current Develop ".II/Illridd, M. S., Brown, H.. &,' Crnwford, M. II. (I !lH4). TIIIIIIIIIIIlI',lulll,IoII ments in Anthropological Genetics, Volume III. Black Caribs: A Case ullol ypes in the muck COl'ibs Rnd C.·coles of 1l(~Ii:lo(' Ulld SI. VIIIl'I'I,I. 1m Study of Biocultura1 Adaptation, pp. 13-35. New York: Plenum Press. M.II. \.~I'Hwror·d (ed.), (;UI'I'ellt ]levelopmcnts iIlI\I111I1"OI)(,101~"'II1 (;'0" ...1,,00', Devor, E. J., Crawford, M. H. & Bach-Enciso, V. (1984). Genetic popUlation Vohl1l1c III. Ull.lck Carihs: 1\ Cusp Study of lli"('IIIIIIl,,t1 I\dl/!'t II t 'ull.. structure of the Black Caribs and Creoles. In: M.H. Crawford (ed.), pp. :14:;-:lli;.l. N(;w YOI'k: I'I('I1UIII I'I'I)HS. Current Developments in Anthropological Genetics, Volume III. Black 1"',01,,1", II, (1!1~11). '1'11(: III1...k ('uril" "f nl'iti:·dl IlulId,"'",;. VtlWJI\ 1'lIl1d Caribs: A Case Study of BioculturaI Adaptation, pp.303-333. New YOI'k: 1'111 "i,·" IlOll:: ill 1\111 hr"l "'I"I~Y. N". 1'I. N,'w y,,['I,: 11."'[11\"[' ;'1'" Plenum Press. I,'nulld"tloll. si(~klc-l:ell Firschein,1. L. (1961). Popuilltion dyllllillics of th':' trnit ill the 11111<'1< :;illI'~hc1.,.t t ~11 1,'1,,410, ('. d,' (;oll'.l.,I1,'1., N lot :1 1 ,'41 1\11. (Iqli',). 1':1 1:!lI'IIII' I l''I'11 V BI'it (;I'lIlnll /I [w',I'i('Il11 ,IOIII'rIlIl CHribs of ish 11011<1111'11:;, /\111"1'1<'11. "f I'."IIC· 11(' «tli'IIII1', fllla·d.)j"1111 "t 1.~lIli·n ICl'l ('lIdl",,', Ill' t'nl',H NC'j~l'tI tlt~ I,IVIIII' l'iil 1111111:111 (;('111'1 u'!;, 1:1. '~:u :~\,I1_ 180 Crawford Guatemala. Reimpreso Revista Collegio Medicina, Guatemala, 16, lllSTORICAL AND DEMOGRAPmC FACTORS 83-86. AND THE GENETIC STRUCTURE OF Weymes, H. & Gershowitz, H. (1984). Genetic structure of the Garifuna AN AFROAMERICAN COMMUNITY OF NICARAGUA population in Brasil. In: M.H. Crawford (ed.), Current Developments in 1 2 3 Anthropological Genetics, Volume III. Black Caribs: A Case Study of G. BATTISTUZZI , G. BIONDI , O. RICKARDS , Biocultural Adaptation, pp.271-287. New York: Plenum Press. P. ASTOLFI\ G. F. DE STEFAN0 3 1Dipartimento di Genetica, Biologia Generale e Molecolare, Universita di Napoli, Napoli, Italy 2 Dipartimento di Biologia Animale e dell'Uomo, Universita di Roma "La Sapienza", Rome, Italy 3 Dipartimento di Biologia, Universita di Roma "Tor Vergata", Rome, Italy ~ Dipartimento di Genetica e Microbiologia "Adriano Buzzati-Traverso", Universita di Pavia, Pavia, Italy. INTRODUCTION Peopling of uninhabited regions, migration, intermixture ann isolnl iOIl '''Iv<~ certainly played a major role in the evolutionary history of hll1l1l1l1 l'''I'ulations. The communities of Afroamerican ancestry spread nlolll: tI", tlll/llltic coast of Central America and on the Caribbean Islands provid" lin "\'I' " hUlIl/ln I?opulation and their relative importance in the determinnl iOIl of Ib "<\111'1 ie structure. These Afroamerican communities are thought to be the result of /I "'''''I'kx process of admixture involving, to an extent which varies frolll Ollf' "l>IIIIIIUllity to another, various African peoples, mostly from centrnl nnd W<'~;f 1' 01 11111.':1, 1971; Salzano, 1971; De Stefano, 1979; De Stcfnno ('I /II, Illfl:~j , '1'lIwftn'd, 1983 a,b; De Stefano & Calicchia, 1985). The present Pllplll' 1'~IH11'h II... l'I'''lIlts of the analysis of historical records, derno(~rnplly IIl1d 1~"II.'tI.' II 11,'1111'" of the A fronlllerican J)opulntion inhabiting t.he A tllIlIl i(' ('011,,1 of III """lil~lIl1, ill nn attempt to reconstruct the patterns 1hn 1 hllvp. If\( I 10 11 ... \""'1'0111 ~. 1'1 H ~ III HII. EARI,Y IIIS'I'ORY 11111 " .... IIIl' "0111111'1 wit II 1':UI'PI"'III1" till' "'l'I'il PI'Y "f N1I'I1I'II1(UII WII:I '11l111"11 i,y jlld/lI11 1'1'1'1111111'''''' wllll/:.' IIl'1i~1I1 1111(1 11111"'1'1,1111111111;1111' IIl'j' lilll y,,1 fllily dll.hll,lllf.)_1 (1"11'.111'." I). TI.c 1 ('lIlt1fll.'1\1I IIl1d :11111"111111 IlIdlllll". Vtwy HI(I'lv l~f'llIllhl