The Affinities of the Antarctic Wolf (Canis antarcticus)

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  • 382 YR. R. I. POCOCK ON

    29. The Affinities of the Antarctic Wolf ( C m i s anfawticrts). Bp 12. I. IOCOCK, l.I C h l K l t G l . of nIammals.

    [Received aud Read April 8, 1913.1

    (Text-figures 70-74.)

    IXDEX. Page _._ 383

    384 391

    1. Published ricas on the afinities of C. nntarcticzhs 2. Skull clraracters of C. antarcticus a i d C. latrans . . . .,, ._ . .. ... 3. Esteriial oliaracters of C. antarcticus and C. latrans ... ..,...

    The story of Cui& ui%turcticus has heen told by Darwin *, by Hamilton Smith j., and more recently by Mr. Bupert Vallentin from first-hand information, and by several authors indebted either to Darwins or Hamilton Smiths account, or to the accounts of tmvellers who visited the Ealklanrls before Darwins time. Iteferences to the literature clown to 1890 may be found in Mivnrts Monograph of tlie Canitla?, published in that year. According t o Mr. Ballentin, d%7& ct?~tcwct iez~s becxnie extinct in 1870, without leaving a trace of its former existence in the Fidkiantl Islands ; and since all the known material of the species appears to he preserved in London and Paris, I have atteniptetl to supply tlie want expressed by Allen 4 by figuring a skull of one of the specimens in tlie British Museim. I have not, however, given detailed ineasureinents of the skull, because these may be found in Mivarts monograph and in the paper by Huxley mentioned below.

    Some six or seven yea.rs a.go, when trying to identify some South American dogs exhibited in the Zoological Gardens, I took tlie incideiital opportunity of looking n.t the skulls of a few of tIie species of Keotropical Cmida? contninecl in the Ihitish Museuin, to learn, if possible, something of their ;tfiiiitics to one nnotlier and to the better 1mow1~ species inhabiting North Anierica and tlie countries of the Old World. Amongst the species examined were Cc~,nZs untccrcticzis, the so-cdled Wolf uf the Falklaritl Islands, m i l Cunis Zutrms, the Coyote or Prairie \volf, which ranges roughly from Cannda to Mexico. The exrniiriatiun was inade without any intention on my part of Rtlding to the literature of tlie subject, TT-ith which I was only acquainted in a very general \my ; a i d after satisfying myself that C. a~~,tcwcticw was relat.ed to certaiii Neotropical forins, of which C. t h o u s (= cnncriz*orzcs) may he t&en as a n exainple, nncl that the afinities of C. Ictti-ccns lie with some of the so-called jackals and wolves of the Old World, I was contented to let the imtter rest.

    * In Watcrhonnes Zonl. of 1I.M.S. Beagle, i\laninialia, p. 7, 1839. + Iu Jnrdines X&t. Libr., IZliilIiitialiii, is. 1. 282. cliiioirs, sl\ iii. p. 45, 1904. Tlii.; ]xiper is qiintrrl liy smile nf t l i r iiitwwtiiig and piixAiiig poiiit,s coiiiiected with iwmiril i n llic Field, Oct. 1 , 1904. Uiiir. Espcd. l:itagoiii:i, iii. lit. 1, 1. 153, 1905.

  • TRE AKTARCTIC WOLF. 383

    Rut in the summer of 1912, I received for review from the Editor of Nature a copy of Dr. R. F. Scharffs volume, Distribution a n d Origin of Life in hinerica, 1911 ; and when I found it definitely st:tted therein that C. cciitai*cticics is closely related to G. Zatrans, and when I saw the obvious difficulties in which Dr. Scharff was involved in his attempt to explain, on geo- graphical grounds, this singnlar :Itfilintioii, I ventured to reassine him by remarking, in effect, t1i:tt his belief W R S devoid of morpho- logical fonndation.

    Now, an author who compiles a volume on zoology of the size arid scope of the Distribution and Origin of Life in America cannot be expected to verify :dl the staternents of earlier and con- temporary writers. Nor in the present instance could Dr. Schnrff be justly criticisetl for not travelling to London to examine for liiaiself the preserved material of 6. antamticus, of which, i take it, there is no specimen in Dublin. Very naturally, therefore. he trusted to the verdict of others, and promptly replied to my remark with a request for my 1-easons for making it. Rut since J. coiild not ask the Editor of Sittnre to give ine the necessary space for justifying the stn.ternent I had made, I pletlged myself t o do this elsewhere, and the matter that follows is an attempt to redeem that promise.

    The acknowledged source of Dr. Scharffs opinion about the niutunl affinities of C. cmtarcticm and C. latrcins was the followin= passage in Mr. Lydekkers Geographicnl History of Mammal; 1896 :- Of the two indigenous mammals, the most remarkable is the Falklancl Island Wolf (Canis untnrcticz6s), wliich differs ~narkedly from all the Canidze of tlre nrainland and is apparently closely allied to the North American Coyote (C. latrans) (p. 140). I therefore wrote and asked MY. Lydekker if he wonld kindly tell me his reasons for this conclusion, and he informed me that he took i t from Prof. Huxlegs classic paper upon the critiiial arid dental chariicters of the C:initl=, published in the Proceedings of this Society, 1880, pp. 238-288. Upon looking rip this pn.per I find tlie following passages referring to tlre two species under discussion and bearing upon tlie question at issue :-

    (1) . . . . . Rut sometimes there is a well-defiried though coin- pm.atively narrow s:tgittal area,, from t>lie centre of whicli a. lorn s:igitt:tl crc~st~ rises. This is well seen in some J:wkals, arid especially in C. rcibtc~rcticzcs (fi. 250).

    (2) In the large size of the iipper niolars . . . . . C. anturctic.rcs presents the closest approximation to some specimens of C. Intraits (p. 266).

    ( 3 ) From the range of wriation of (7. crmcrizorzcs it can hardly be doubted that the examination of more extensive materials d l prore the existence of a.ti uninterrupted

    : series of gi.ad:htions froin Cr. w t d w to C. ni~tarcticzcs and C. jubrctits (p. 266).

    (4) Seven crania of C. I c i t ~ c c m , mhen measured, exhibit a con- siderable range of rariation, tlrough probably less than a larger series mould show. Rut, as they are, I mnst collfess iiiyself iuia1)lc t80 f i i i t l :nil inilmrbaiit I)reak in the

  • 384 MR. R. I. POCOCK ON

    series of grwlntions of crmial and dental structure between C'aiiis l a t r m s ant1 C. aiatarctiocs on the one hand, and C. latrans and C'. occideiitnlis on the other. . . . . . I may further reiiiark that I can discern no difference of the slightest importance betuleen skulls of C'. b t m m and those of some of ow- domestic dogs (pp. 272-273).

    (5) In the genus C'ccnis we have . . . . . as a lowest section the species of the G. cancr iaoi~~s and G. vetulus type (an- swering pretty much to the Agiia,i*m dogs of IIamiltoii Smith), the Hacaline section (C. uzcreics, C. a?ztJLus, C'. ~iaesontelas, C. antarcticits, C'. latrans), and the Lupine section (C. Zicpzcs and all its varieties) (p. 286).

    Whether these pxigraphs justify Mi-. Lydekker's statement * that C. u)Lta.rctic?ts tliffers markedly froin all the Cnnic-lix of the inainlantl of South America, and is xpptrently closely allied to C'. Zati-ans, :tnd Dr. Schnrffs extension of this to the effect tliat C. antctrcticzcs is certainly closely related to C. latrcvns, must be left to intlividnii.1 judgment.

    Pari\gr:*pll 1 merely points out one resemblance between C. antarcticus and some jaclmls. Pnragraph 2 similarly points out one resemblance between the two species, but conta,ins no suggestion of affinity between them. P:tragrnph 3 may be interpreted as suggesting affiliation between the extreme forms of South American Uanidze represented by C. eettc1u.s and G. jtcbatus, with C. ccntamticus lying midway between them. Paragraph 4 is more precise and stxtes that there is no im- portant strnctural break between C. avrtnrcticits and C. lntmns, and that the latter similarly intergrades witli 6'. occidantalis and C. fanzilictris. Parxgraph 5 , on the contrary, definitely associates G'. antctrctieus and 17. lutrcms, mcl ah the saiiie time severs the former from the group typified by C. .c;et.ccZits and the latter from the group typified by C. licpics 01- occitleiitalis, an arrangement not easy to recoiicile witli the views expressed by p:w:~gr:iphs 3 and 4.

    Afte r reading Prof. Huxley's paper mther carefully for eriligliteninerit on this subject, I niust confess that I cmnot form any clear idea as t o his views of tlie d in i t ies of the species lie discussed, except in n broad sense.

    If tlie srtbst;ince of paragrapl:s 4 ancl 5 aford some justifi- cation for Mi-. Lylelrker's tlecluation respecting t,he relationsliip between C. u~ztarcticl-ls ancl C. lutrnizs, it riinst, he admitted that p:iragraph 3 does not support the contention that C'. aiztnrcticus is quite iinrelntetl to the species of Ca,iiitl~ inhabiting the Sonth Anierican mainland. IIowerer that may be, the conclusions forced upon me by the exaiiiinn.tion of five craiiia of C. cmt- ccrcticics and twelve of (7. latrams 7 in the British Mnseum and

    *; In the article iii 'Tlw Field ' (Oct. 1, 190&), nborc rrfrrrrd to, MY. Lydehker evinces lesa ahsuraiicc 011 these poiiits; Init lie c\.i(leiitlg corlld not bring liiinsclt to

    t the anthority of Husl I use this term in i ts (11

  • THE AXTARCTIC WOLF.

    Text-fig. 70.

    385

  • 386 MR. R. I. POCOCK 011

    the Museum of the College of Surgeons are:-(l) t,hnt C. ant- cwcticcss and C'. Iatmias are not closely allied ; (2) that 6'. alstu~-cttc~cs is niore nearly reLited to the C. thozrs (= cuncrivorus) p-onp of South American Ca,nid;e than to G. latrans; (3) that C'. lativ,iis niiist be affi1i:rted with such Old World species as C. pal l ips , C'. hpuster ancl C, unthzcs, and not with C. unta~cticus, Tlie first and third of these conclusions are borne out 11y the external characters of tlie two species concerned. My r