Document 4Q4eQa5Ym1QXRJ38835JLrKvG

1290 NATURE VOL. 22 DECEMBER IS 1*70 , 't .t Vi/ VI' *i . egg per eob or water hilsj if this were not tho com even mUamo aottlshnem mM not bo (tvound by selection. JfiU4ti seems to havje this habit in nature" in pit* of n eonlrery impression given by Kirkpatrick". But why, V tho imm m correct, are more convincing examples of spit* hard to And t First. I suggset. beoauee nil notions do tod eoawtlting. Beoond, bsenuso on animal will not normally hav* any woy of reoopristag which Othsv nsnibin of Ms species hm leoo than average lotationships. Memory,local odour, and nearness to plaoo of birth may pormlt roe^gnition of eiooe relatives, but this loaves a remainder whooe average rolationohip wilt bo only vory slightly loos {in liift populations) than tho total average. Moraovsr, with common pattomo of fit* . tho _ . individuals moot likely to __ enoousured ara Ihs i likoly to bo moot related. Third, because single popul i that are oo omall in "offaotivo aiao'* aa to have h w klly muoh different from aoro mutt bo ia a precarious liitoo already, and tho oaleotioo of a gene causing q>ita oan only Kaoton thoir extinction. If, on tho other hand,' them M a oompooito population made up of many such' small pvooarious dements. either wo moot rooogniso a proooss of group oelootion in whioh thooo elements that hays not yot boon overwhoimod by oMsh and spiteful mutations roplaos those that have, or wa must oonsidor relationship against tho baokground of tho totfl population, ko ooomo tha natural point of view if the subpopulationB am emitting and roooiving migranto. fakm together theee; point# suggest that my previous aooount is not serfouMy incurate for social behaviour in realistic oiroumstanoss. The point that has now been brought into focus, thi adaptiveness of solffshnssa and pita in panmiatis popiilaUoql. suggests one raaooo why panmixia hardly ooours. When It dose ooour, the aoleotion of sdfUh traits reduoesmoan fftnem and ths popular- Is foreod to retreat frhm Mo loss favourable habit If M remains panmietie tho tsood may oootbuo nod I toMUnotioa. If, on tho .other hand, tho population breaks into isolates m population doelinss, a brooding otruoturo may be aohiovad tn whioh farther spread of mMshaeos, ana henoa farther deelln*, eon bo rsMMod. | W. D. Ramtvto* Imperial Oollogo Field Station, Sttwood Park, Asset, Berks. i mlmi pair It. iTO. 'RmMMn, W. r>. Am*t. MM ff, tH (IMS). MesMItee. w. n , J, thm. .T.K1M4). HMiNtea. W. D., ta Mm Of# 9ml: < hNn OiW NMw (fiM imWmnimlmMNMm Tmlftimn. f- 1SSS> (la dn pMi). rim, o. a., Ftfvrv.rr. isstisier Wrbtel, ., Amr. MM , M. SSSUSM). wrgai. fliMim. it. m (ism). wrteM, i., im. Bmmaa it, m (lssu . Wr%hl. B. get. Am*. MMM, fri. . MS (IStf). OrteH. a. H., h4 willa *, ,, Bmtm. . ?M (ISM). . " NMtet A. Hii-IpO MUM Vwfr. Tim. ISS4). {wtt,r. a., ua mmh i; pm. jno. MMmM. b* a. m, in otsti. * KMnMa, y. w,, t*mi iitaii t>oNw (Lamouss, limit issn. H dh*r, M. 0., C*W . IM (fOttt Sotirca of Polychlorinated llpteifl Contamination In tha Marina Envlronmant | Bntca residues ofjpolyoMofinatad biphenyls (FCBs) were idontifled in SwodUh wM^ifsi, they have been reported ^Jn many marins'apeoiee^*. Samples of marino fish and mottuses from Ssottish 'waters have been analysed for t orgonoohlorkw rsetdues at this laboratory on several oooosioas sines IHa, and ths aonoanteatisns of FOB footfno* dstaslad to three samples have but generally WjRX from U Flrlfc of drib. Therofor. wid, TlHMr of samples from this area was used in ths autumn of IIH to try to establish tho route by whioh the PCS tesidiNv reached ths fish. Bompleo of the water turbos Sim and sub surfboo wator wore token at various poinls in |g estuary, and also at l-mils intervals along the river to ths Mein of Glasgow, to detect any local dieetevM containing PCBe. No PCB teaidues eould bs bod (limit of detection tn water. I part In 10) end -irrailu of eBuonto dbcharged from trunk soworo into Uw uharv and in tho Qlaegow area also showed no slgnilhani oonosntrattons of PCBs. Conomtratiorw in aopptanktoa by comparison wore loss than fH>J p.p.m. (9 parts in Ifte), and in chtpeoid fUh up to I t p.p.m. (both exprnssnd ,m wet weight basis). Polychlorinated biphsnyb are produood by the enn* trolled chlorination or biphenyl, and are mads available for industrial use in various forms, mostly as linuid* rf different viaooeitiee, eooording to tho dogree of chlorine- tion. More than 900 oompounds are thooretioally pnssiblr, and each aommereia! preparation contains several indi* viduat PCBs with different arrangementa of ths chlorine atoms in tho molecule. PCB compounds found tn wildlife samples, using gas liquid ohromniography at about 100* C, have been ahown to contain mostly six to seven chlorine atoms', althmigh oompounds with more chlorine atoms may not be sufficiently volatile to bo detectable at thie temperature. For comparison with the PCB residues found in wildlife, a PCB mixture rmlikih^ about M per oont by weight of oMerino Is commonly usod as a referenoe (for example, 'Aroolor IIH', Mon santo Ltd). In Britain, effluents froifi industry apart from three whioh are unaoooptablo are usually passed to purifloation works for treatment with domestic a ^ Samples of crude sewage sludge from such worksite! Glasgow and adjacent areas hsvo been analysed for PCBs. Ths sludge from this area is transportad by boats to the estuary and dumped in deep water % mites smith of Oarrooh Head (Isle of Bute), at ths rata of about a million wot tons per year. It ean therefore const!lots a source of entry into the marias environment of coins industrial waste products. TiMi i. miini ms xnostt is ui-upn wniumississ m* s it too* iti Hit iti sss in ass ass m * i""llii8i85i ita p**h inrieSM rs'*i>ni n *Mc*. t ful hflstit- ISO for nAsm. Although the extraction of organoohlorino oompounds from soteage solids (using a mixture of a-hsxano and isopropanol) is beliovod to bo less efficient than extraction from water, it was nevertheless found that many of ths sludge samples gave ge*liquid chromatograms similar to those of PCB mixtures. Table 1 chows the proportions (in terms of relative peak heights] of the major peaks in typical chromatograms, as identified by their 9, values (retention time at 900* C relative to dieldriln* 100). The column used wee puked with 10 per cent DC-100 silicone on *Chromoeorb W\ PCB oompounds were separated from all major organoohlorino psstMde residues, except pp' DDB, on sflioa oolumne'. The peak pattern for sludge A is olosely similar to that ofa PCB formulation containing about 00 per oont by weight of ehlorins (for example, Aroelor ltH'), but the pattern for shadae 9 suggest* that It contains those PCBe of higher ehlorins content in a greater proportion than A, and is similar to ths pattern produced by 00 per cent chlorinated products (for sxampts, 'Aroolor ISSO'I. . On ths basis of wet weight ofcrude sludge ths ir^iikulfit eonoentretions of PCBs. using `Aroolor 1994* re refersues, b fifteen samples were fo the range <0-1 to U s.s* (If `Areolar IHO* M ured at refbeoea, tha eonaaptrafiore MONS 063973 It th wMghet Anetlym Wbw pamibb Mwd s aautd b uepond af PCM have bn labemts I tha Freskwa Pitlochr "srr `ara n-Stea mis: "Baf lUteti Harri In man*  t t r iM f ii ;< < e ri)> 7 trrr^ r; ^ iM iu r t t i* 1 NATURE VOL. 1I D^CCMRER < 1*70 )mr.) |r Imitf of dry mutter the vaImi ` ` > lM. JMMn. (velum uuenmeted fur ... .. jfrr). T,,h w' riow p*lMt*a ifm M- d*t MM M thM OMMOMi nd two plant* worn found It ft MiWoBtijr Ugh mwwIwtioM of PCB (90>1I0 pfjn. dry wthh), B% liquid egfaente from ttuw plants toolslnta oompmtivoty intlgniftotnt tonoentra* boat of PCB. It ha* jprovad Jmpoaalbl* to loaato tht origins of Iht PCB dtodmrye* to the sewage plaaolt oon* arned, beitust etveral hundred factorise are Jinked to thteewera. Hot okerntoth oaa be ueod for many industrial purpoeo**, but It to not Wn how many of the pomhie am are exploited hi tl4 Glasgow area. Il Unit seems noitoMe that the PCB* io the Clyde ecosystem mult oon Routine dumping of eruda towage lodge Bern treatment work* in Olosgow and adjacent treat- An average NtWtntim of PCB of tha order of I pfja. {at faunain flftos* aanplee ofwelahidgo weighted Miordhif to the proporilone dumped) would be equivalent It a dteetmpe In the Ohms estuary of Uw order of 1 ton of PCBe par pear. Fw sample* of erode stodge from "........`.....`... f,d__u_n,g_a_l_4T t.h..e N.Noorthei rn -IH-eh -ftee*), wh" i'c*h were analysed at lh Bofnham*on-Orouoh Laboratory of the Ministry of Agrtoul ore, Fisheries and Pood (personal temmunfealion from I. X, Portmann) using aimitar techniques, contained between 0-1 and I p.p.m. (wot weight) of PCBt. If tha e lean average of I p.p.m. dumped at a rata of frf mUlto tone of dodge per year, about I ten of PCB beam per year would be dtooharged. Analyst* bp the tame leborntoryof eamplee of London > stodge have d^rn that thee* contain lam PCB, lyptotUdy ofthe order ef t pt.m. About 5 million tone a..re. d_aimpeedd eoiflf IMV. , m. n' fetouery. again equivalent to about a ten of POB topraavo. Where thtofermoftoudg* diepoml to practi_s_e_d, tha .Ti-CB.i. Aly feetobto. Beano coasta) towns, however, dtoehitgo oma* ii- _ a . --. i- a. --.-- ai----a a- it. M (M,, _ I 4 aoeh aaeee any POB* present eooM be enidiii to War the ooocyetom adsorbed to is praettoed In inland . i i, eooM lend to the introduction ef PCS re_s_i_d_u_a_*_I_n_to__the tosnrtmirtol seoeystom by transfer through food ehantnao. |foohhr., howovor,. no PCB residue* tontiim deteofed In freshwater ftoh in Bootland at thto ** MhaS the City of Manchester Riven ttopartment 3 J- to mfoi-- (*) m. i. In the herring gull (lerw ary*nfahw), the ehtek ketrHitq from thhie* fthi'rd* ogg su"itors a muc*h `h*ith* er mortality ihan either <of ito sibling**, although the hatching eurrm* to the earoe for all throe eggrf. In a eerie* of egg transfer experiments otrriod out on the Id* of MayTSentland, it has been poaeible to demonetrato at leaet two faster* contributing to thto differential mortality, namely the is* disadvantage and the sequence of hatching, because third laid eggs normally hatch laet. Although the survival of ohiofce from third gga Inoroaeed when they wore the first to hatch, it wo* etui lower than that of Ho eiblinge. .* .***.wj jJjfcTJl 5^ ^^ tuff Cauoke rrosn more *oen i,twmm or nnewn uorame* th. nrvinl of tb. ehlok. ww Mmd by h baan at hatohing. Moot of the mortality ooourrod In the Am woek after hatohing*, and the mortality after that time was independent of the dao of the *0 from whieh the ehiek hatched. The fate of ehieka within the Bmt erven days of Ufe was therefor* grouped tooordlaa to eng volume and eaquene* of laying (see Table 1 and Pig- ) TeM* i. ewK* aearum wimr a tn e lAvean* oeariu* m tnd the BetentiAc Pranoh ef the Creator London Council far sewage eamplee. I A.T.Hmps* Ptoflhwatcr FisbH** Laboratory, VMoohry, ,T Bootland. Issdvto. Atd ..* H MV* IRMN.A.T.. wen*: tm (en Bh Bin--a. t. 0., mi Etoen `KflMtt.--i r. H. &. tsi it Ten E. IL, 9+m, taM*. tlAMk. A , WA IL, U< ONaM. ARM MMaMIMMIM* I ' hU. A. T. ui INwNaE. 1. >,., M. Ul I1M.V IwmHa Alt, Ml M. IMA * r*N>*i A IN timx lUtetimuMp btwMn Km Six* and r**> hrttMM CMck Mcrnllty In th* Hrrln| Gull (Larw r|wiWi) " b/iMVwnuM w4. (n>M IWM m SoMk h mmIW Uan * M m-ee an mW TdC ^ct an mot Hr *nl mrteVtr -- . tot - ttNelwerUMr ICO !0 es s. 3, l I, 2 iti nme -- hi etc ya rn 3. lsr. S, S, S. S. 5. 3. : For aaeh egg of tho laying eeaueoea (referred to ee the a, h tnd e egm), there it t eigniAoant potitlvo oortoiation between egg eue and ehiek survival (P< 0*001), giving a range from tpproximttoly to per eent to 10 per ernt survival. Thto relationehip to sTmilar hr tin Bmt two rin a olutoh, but although the elope to the came for third egg, the survive! to 10 per amt lower fat rgps of the same eiae. Thus the survival ef tha third hatohrd ohiok to lower than would be smsefd from Me torn, but the md important factor m dttonainiag pest* hatohing survival m the tom of the egg. Nearly tn the ehieka from cgp emtltor than W em1 died man *A*r hatohing. Oa^lperee^ of a egM bid were below thto the, and M per omit of there were egge. mi toe* to poaltieely eonelatod im seven ineluding yofa weight and IMd (hrmana aoWbla] a* M to la ether maotoa'. Purthsrmere, tht \weight of MONS 083974