Document VjjD0Nw5Oq6yoEeeyMyoKe6w4

picking up and holding food in one free hand. 11c also waddles forwauls v-ttli one or bo'll hands touching overhanging objects but not providing suspensory supps'rt for the body. He sometimes [moves over shot l distances with both forclinibs raised and outstretched above his head. When waddling on a wet floor, he slides his knuckle walking hands in front and without breaking contact with the substrate. As one foot swings forwards, the load is borne almost ex clusively on the contralateral foot and haunch. When moving rapidly on a dry substrate, he raises into a scmi-crcct jquadrupcdal position. He places his hands in list walking postures wherein the fingers are lightly Hexed and the skin onjthe dorsum of proximal phalanges 11 -V makes con tact with the substrate. 'I he hindlimbs are extended and the ischial tuberosities are well above the substrate. The back and head are inclined forwards. The load is borne not only on the lateral aspects of the feet but also on the lists as the subject uses a "diagonal-sequence, diagonal couplets gait"*. He moves rapidly on a wet door with alternate steps of the hindlimbs ;but without raising his fists from flit substrate. Once he briefly slid his right hand forwards in a knuckle walking polslure while his left hand remained u fist. The right hand bore [only a moderate portion of the load because the forclimbs remained protracted throughout the episode and the body did not pass over the hands. When leaning forwards to investigate or to pick up orally objects on the floor and when descending head first from low elevations, he consistently places his hands in fist walking postures. In summary, although Felix often places his hands in knuckle walking postutes, he rarely supports a major portion of his body weight on knuckle walking hands. Instead, he jplaces his hands in fist walking postures when support is required for loads that are significantly greater than the weight of the forelimbs themselves. By fist walking he probably avoids stressing metacarpophalangeal joints 1I-V which, in orangutans, lack special morphological adaptations for knuckle walking of| the kind possessed by gorillas and chimpanzees'"4. Before 1967, the primatological and anthropological litera ture was confusing and misleading about the terrestral hand postures of great apes because some authorities uncritically and sometimes erroneously designated orangutans, as well as chimpanzees and gorillas, "knuckle walkers"'. One of us (R.T.) recently described and classified6 the variety of hand postures often used by captive orangutans during terrestrial locomotion, and concluded that only chimpanzees and gorillas should be designated knuckle walkers. He stated that "orangutans do not and, moreover, cannot assume the digitigradejliand posture of the African apes"''. This statement should now be qualified and restricted to comparisons be tween great aces engaged in scmi-crect quadrupedal progres sion with "trot" and "diagonal sequence, diagonal couplets" gaits' on non-lubricated substrates. Although Felix Iras not been observed to knuckle walk like an African ape or to place his hands in knuckle walkin ', postures during "crutch walking" as do chimpanzees and gorillas, lie frequently rests his hands on the middle segments of the fingers and thereby supports oil them the weight of Ins lorclimbs and perhaps also a portion of his head and upper torso weight. Because !a highly advanced arboreal climbei and arm swinger like an oraV| i-euian is able to p' lace his hands in knuckle wa-lking postures suggests that the .m.estois of the African apes might have bcenj similarly, or to a greater extent, predisposed to knuckle walking by their own special at boreal heritage. Man. too, ollen rests lus Hexed lingers in facultative knuckle walking p.jxiiircs, as may tv witnessed in cert.-an public speakers ami li'utl'.ill biicsincn. .Milioui-li the ihuaih is usually used piniuim ih!> at a supporting strut during human knuckle walking i'I'Cuics the fact tn.it man has a piedisposition for such pkwelna 1 of manual digits ll-V may fig at least as prous .iliw te.i i". olutionai y inlcicnccs a; the facultative knuckle ss.11i in-: cl! an orangutan. It may thus be argued that man passed through a phase of arboreal climbing and suspensory posturing somewhat more advanced than the antibrachiutionists and prcbrachiaiionists have admitted into their models'-'. Another optional model would evolve man, orangutans, or both from knuckle walking ancestors. Such a theoretical possibility cannot be ruled out on the basis of available evidence but we do not choose to subscribe to it. Wc thank William Dav is and Lcland LaFranec of the Chicago Zoological Park for their assistance with videotaping and photography. This work was supported by the National Science Foundation and by u l'MS research career development award from the National Institutes of Health. Department of Anthropology, Committee of Evolutionary Biology, and Biology Collegiate Division, 1126 Fast 59th Street, University of Chicago, Chicago, Illinois 60637 . Kussei.l Tuiti.e Chicago Zoological Park, Brookfield', Illinois 60513, and Biology Collegiate Division, University of Chicago Benjamin B. Beck. ` Received September 20, 1971. 1 Hildebrand, M., Anter.}. Pliys. Anthropid.. 26, 119 (1967). 1 Tuttle, U. H., Amer.J. Phys. Anthropol.,l<i, 171 (1967). ' Tuttle, R. H,, Science, 166. 953 (1969). 4 Tutile, K. II., in The Chimpanzee (edit, by Bourne, C. H ), 2, 167 (Karger, Basle,'New York, 1970). ' Straus, \V. L.. A hut. J. Phys. Anthroiml., 27, 199 (1940). * Tuttle, R. II., Anter. J. Phys. Anlhropoi., 26, 171 (1967). 1 Tuttle, R. H., Sci. J., SA, No. 5, 66 (1969). Interpretation of Persistence and Effects of Polychlorinated Biphenyls in Birds Peakall and l.inccr* suggest that polychlorinated biphenyl. (K~Bs) found in nature are derived only from highly chlorinate! commercial mixtures such as 'Aroclor 1254'. Residues o lower chlorinated mixtures have not been reported in spin of their predominant industrial use. This may be due cithe to utilization in enclosed systems or to more rapid metabolisn or excretion. To demonstiaic which residues remain aflc PCII feeding, pigeons (Colombia livia) and japanesc quai (Culornix rotoruix jaoanica) have been fed `Aroclor' mixture' Twenty-four separately caged feral pigeons w-re fed a libitum for 28 days with wheat dressed with 500 p pan. 'Aroclo 1242'. Six control pigeons were fed wheat. At the end of th feeding period six test birds were killed by cervical dislocatioi and the rcinaiuJer returned to a diet of mixed grain and pulscw Ivfore being killej in batches of six at 28, 56 and Ins day.tighlccn 4 week old female Japanese quail were caged i hatches of six. One batch v.as fed ad libitum for 20 days wit `Aroclor I2.4'' diessc-d food at 250 p p.m , .mother wit 'Aroclor 1254' dtewed food at 250 p pan. and the remainm batch left av controls. All buds were killed 24 h alter x*-ill dr.tv.d of thessctl food. This regimen allows compariso with other quail feeding experiments'. Immediately alt' death, lire.- a muscle, liver, brain and omental fat samples wet removed bom pigeons. Similar samples were removed Iroi quail with the substitution of heart for breast musetc. f DSW 192870 il J . STLCOPCB4052038 NATURt VOL. 22'i MARCH 3 1972 35 Ttblo 1 f.'.L'.n Tot.il FCB Residues (p.p.nv). tumid in Ou.nl Tissue utter I er.leig j/.ioctor 1242' .md 'Aiodor 1294 B1 290 p pm. lot 20 Days Tissue liver I Henri ] Brain i Omental! fat ____ ii Aroclor 1242' 17.0 +2.6' 3.210.7 7.8+ 1.7 123+17 * All figures ate mean of six birds + s.c. I 'Aroclor 1254' 2K.I + 7.9 7.01.1 7.7 +.2.3 3043I portion of liver was taken for preparation of nticrosomcs1 and determination of cytochrome PJ50J and microsomal protein4. The remaining liver and the other tissues were extracted by the method of Taylor ft al* before gas-liquid chromatographic analysis using a 3-fool `Apiezon L' column* at 200 C. j The complex nature of `Aroclor' mixtures.makes the expres sion of results difficult. Because gross changes have taken place in ourj experiment we have chosen the method of Risebrough1 front those published and compared the sum total of peak heights'with a l,l-di(4-chlorophenyl)-2,2-dichloroethylcnc (DDE) standard, which in turn was related to a known weight of `Aroclor) 1242'. The mean results obtained front the batches of pigeons are shown in Irig. I and from quail in Table 1. Regular checks made on excreta revealed no gross excretion of| unchanged material. The presentation of changes in the gas-liquid chromato graphic pattern of PCB isonters is also difficult. Most workers have preferred to suggest that the patterns which they have obtained resemble one of the commercial mixtures, leading to the general conclusion that PCBs remain unaltered in the bio sphere. Since wc wished to determine whether birds arc able to metabolize PCBs vve adopted the following method of piesentation| for gas-liquid chromatographic data. A single peak occurring in all chromatograms from fed birds was selected and represented arbitrarily as 100 units. The mean of peak height for each relative retention lime from each batch of birds was normalized to this peak. By this method an average residue "spectrum" can be presented in the form of a I i Fig. 2 Gas-liquid chromatographic ``spectra", normalized to a common peak (stippled column) of `Aroclor 1242' standard and mean pigeon liver residues following feeding at 500 p.p.rn. in diet for 2$ days. line diagram. Fig. 2 shows line diagrams from the livers of pigeons fed `Aroclor 1242', and Fig. 3 those front quail fed `Aroclor 1254'. Other tissues gave similar results. Total PCB residues immediately after withdrawal of treated food show a similar distribution between tissues to those in pigeons fed l,l-di(4-chlorophciiyl)-2,2,2-lrichloroeihane (DDT)". Allowing for the higher feeding level in the DDT study initial PCB icsidues are live to ten limes higher. In the muscle and fat theie is a steady logarithmic decay with half lives, by inspection, of 50 days and 125 davs respectively. Aficr an initial l.ttgc drop in levels the liver residues also follow a logarithmic decay with a half-life of 140 days, 'these figures compare4 with a statistically computed half-life-of 2S days for ITDT in all pigeon tissues (uncertainly in interpreting I'CB analytical results piecludes statistical analysis). PCB residuein the brain reach a maximum and then decay logarithmie.in with a half-life of 50 days. The high liver icsidue level immediately after withdiawal of food ntay he attributable to the rale at which liver receives freshly absorbed PCB. and the initial low brain level may reflect the operation of the bloodbiain barrier'. Total residues in quail fed `Aroclor 1242' (Table I) are higher than those in pigeons in spite of a shorter feeding period at half the level. Food consumption per unit weight of quail, however, is two to thrcc-lolJ huger than that oT pigeons. Residues of 'Aroclor 1251' are generally twice those of `Aroclor 1242'. suggesting, that tins mixture is more ditheult to metabolize or excrete-. The standard 1242 mixture gives a pattern domin.ncd by a few isomers of low retention lime oil our pac-hqunl ihromalogr.sph. There is a considerable iluo-.e in pigeon Itvei residue patterns tl'ig. 2) with pe.il.s of low icl.ilive leleniion limes ......;.i.. ui. ..-a.-.... i i........-.II.....i, i. alow i,,e v.uh.'i.iw d of r I SVV 1 9 2 8 7 1 STLCOPCB4052039 NATUfit VCH. 23fi MAUCH 3 19 Table 2 Mean l icet Weights. Mir.iosdtv.il Protein Levels. Cvlochror P,,,, Lovols anti Residue Levels lot IVieutts ted `Amr.lnr 1242'' bOO p p.m. lot 2d Days and kilted at 0. 2*t. bC and 108 bays altet 1 Withdrawal of Utetsed Food Days lo death Control 0 28 56 168 Mean liver Microsomal Cytochrome Total live weight protein Paso nmol t; 1 i esidues <gl / mg g 1 liver liver P P nt. 6.97 + 0.32 13.70+ 1.07 2.40 + 0.28 0 10.75 JL 0 98 19.30+ 1.80 15 47+ 1.70 15 3+ 1.8 S.78 +. 0.61 17.31 1.51 1l.00l 40 3.6 0.5 9.74 + 0 93 13.47+ 1.72 7.48+0.83 3.4 + 0 1 6.50 + 0.45 12.811 1.40 6.73 0 81 1.8+ 0.2 * All figures arc mean of six birds s.e. Table 3 Mean liver Weights. Microsomal Piotcin Levels. ( v' jctiroi P4 j,, Levels and Residue Levels tot Quail led Aroclor 1 242 and Atoc 17b4` at 2b0 p.p.m. lor 20 Days before Death Fig.l 3 Gas-liquid chromatographic "spectra", normalized to t common peak (stippled column) of 'Aroclor 1254' standard and mean quail liver residues following feeding at 250 p.p.nt. for I . 20 days. Mean liver M icrosomal Cy to :hrome /r,.ial lice Compound wcia.hl protein l\,,, nmol re siduc* fed (g) mg n 1 liver g. 1 liver p.p.m. Control 3.82 + 0.22* 25.05 2.27 5.42 + 0.6-1 `Aroclor 1242* 4.52 + 0.37 31.62+1.27 22.18 + 2.83 `Aroclor I254` 5.08 + 0.22 42.87+1.42 42.21 + 3.31 0 17.0 + 2.6 28.1 7.9 treated food and virtually absent by the end of the experiment. These peaks seem to be readily removed from the body revealing other minor or less electron capturing constituents with a longer biological half-life. We cannot yet be certain that all these Ipcaks are chlorinated biphenyls present in the original mixture; some may be metabolites. Peaks with a higher reten tion time are relatively enhanced over the experimental period. The patterns obtained after feeding quail `Aroclor 1242' have the same general features but `Aroclor 1254' feeding produces less aberration from the standard. The conclusion that the less chlorinated isomers are more readily metabolized is also supported by two analyses on a high resolution capillary column. A standard `Aroclor 1242' exhibited forty-four peaks and a considerable proportion could | be assigned structures10. An extract of fat front a pigeon killed immediately after withdrawal or dressed food exhibited twenty-nine |>caks. Most of the fifteen peaks of lowest; retention time (mainly dichloro and trichloro isomers) were absent from the extract. Peaks of longer retention time (mainly tctruchloro or higher chlorinated isomers) were present in the pigeon and many were relatively enhanced. These'results agree with previous work involving quail'1 and rats''J Theihepntic microsomal systems responsible for metabolizing foreign compounds are sensitive to induction by chlorinated hydrocarbons. The significance of induction is not yet understood but it can be used as an indicator of the biological activity of a compound. Increases in microsomal protein and cytochrome P4,,) arc central to microsomal induction and wc have measured these to indicate the interference hy PCI) residues in the normal physiology of the birds (Tables 2 and .1). Pigcjon liver weights remain elevated for at least two months following withdrawal although hepatic microsomal protein returns to normal. In contrast, cytochrome l'jj, levels are still all thiee times the control level 6 month* after returning to normal diet when PC 11 levels are approximately 2 ppm. and composed mainly of higher chlorinated isomer-', suggesting that ejvtremvly low levels ( < I p.p.m.) of these isomers cause significant elevation of microsomal enzymes. Quail fed either "Aroclor 1242' or '1254' show- similar increases which are far larger'than tlur-e uhiamed from similar experiments involving I >OT !md 141)1.. `Aroclor 1244' produces consider.ihlv more * All figures arc mean of six birds + s.e. induction than `1242', supporting the suggestion above th the more highly chlorinated biphenyls are the most pote inducers. In spite of analytical and interpretive difficulties we c. conclude that pigeons and quail metabolize polychlorinat biphenyls at a rate generally dependent on the amount (chlorine in the molecule. Further work in our laborato suggests that some lower chlorinated isomers arc metaboliz extremely rapidly. This could account for the almost univer: finding of residues of `Aroclor 1254' in spite of the tnaj production of `12.42'. But biological activity depends on t highly chlorinated isomers, which may need to be taken in account. We thank Monsanto Chemicals l.td for `Aroclor' mixtur itnd high resolution gas-liquid chromatography. /Vst Infcclion Control Laboratory, Ministry oj Aytii iillin e, liskeries anil hunt, lolnorlli, Surbiton, Surrey S. I1aii.iv P. J. (K.'nyaxj Received September 16; revised OetoKr 23, 1971. ' I'eakall, 17. B , and I inccr. J. I... Ilian ieme. 20 958 (19701. 1 Human. P. J., Townsend, M. Cl., and Taylor. A. (in the press) * Ornuru, T., ant! Sato. R., J. Iliol. Chetn., 239. 2370 (t+o4). 4 l.owi v, O. II.. Koveh;ou':h. N. J.. Parr. A. t.., and Randall, R. J htol. Client., 193. 365 (1951). * 1 ay lor. A., Rea. R. I and Kir by. (7. VC, Analyst, 89, ey7 f 196 6 Simmons, J. I!., and Tatum, J. O'G., J. Clirnruatay'., 27. 2 (19671. ` 1 Ri.ebiough. It. W., in Chemical lallent (edit, by Herr. Ci. G..a Miller. M. W.), 5 (Charles C . Thomas, Sp-in 'lield. (Him 1969) ~ * Hailey. S., Human. P. J.. Rennisoe. It, D., and Taylor, .- hisieel. A/'t'l. rinnnt.iei'l.. 14. P (19V)). * llakav, I... Sue,urn. Il-lmym. 101, 511 (pint.), Sissons. I).. and Well!, I).. J. ( In rnn.mne. 60. 15 (1971 l, '' Roe 11 tan J. 11.. 11 n Narver I )e Hi a me. M . C anil 17e \ os. R. 1 Satin e, 221. It 'n ( IX,91 " Gram. 17. I... Phillips, \V. I J., and Villcncuve. 1) C.. In Lm I, on. ( nut me l <` licet , 6, HI 2 ( I 4 I I ). DSW 192872 l ! STLCOPCB4052040