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A Phylogenetic Analysis of the Caminalcules. I. the Data Base Author(S): Robert R Society of Systematic Biologists A Phylogenetic Analysis of the Caminalcules. I. The Data Base Author(s): Robert R. Sokal Reviewed work(s): Source: Systematic Zoology, Vol. 32, No. 2 (Jun., 1983), pp. 159-184 Published by: Taylor & Francis, Ltd. for the Society of Systematic Biologists Stable URL: http://www.jstor.org/stable/2413279 . Accessed: 02/04/2012 22:07 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Taylor & Francis, Ltd. and Society of Systematic Biologists are collaborating with JSTOR to digitize, preserve and extend access to Systematic Zoology. http://www.jstor.org Syst.Zool., 32(2):159-184, 1983 A PHYLOGENETIC ANALYSIS OF THE CAMINALCULES. L. THE DATA BASE ROBERT R. SOKAL Departmentof Ecologyand Evolution,State Universityof New Yorkat StonyBrook, StonyBrook, New York 11794 Abstract.-The Caminalcules are a group of "organisms" generated artificiallyaccording to principles believed to resemble those operating in real organisms. A reanalysis of an earlier data matrixof the Caminalcules revealed some inconsistencies and errorswhich necessitated recoding of some characters.The resultingdifferences with earlier resultsare minor.The images of all 77 Caminalcules are featured,those of the 48 fossilspecies forthe firsttime. The characters of the Caminalcules are defined and a data matrixis furnishedfor all Recent and fossil species. A new phenetic standard is proposed for the Caminalcules which divides them into five "genera." The true cladogram is revealed for the firsttime. Recent Caminalcules have evolved over 19 time periods. Five branches correspond to the phenetic genera but originateat greatly differingtime periods. Four lines terminatein fossils. A series of measures for quantifyingevolutionary change is defined,including measures for homoplasy,parallelism, and reversal. A survey is made of these measures and of other statistics of relevance to systematicsfor 19 data sets fromthe numerical taxonomic literature.The Cam- inalcules turn out to be compatible to data sets on real organisms with respect to all these measures, as well as with respect to evolutionaryrates and species longevities. Thus, questions raised by an analysis of the Caminalcules should be of interestto systematistsconcerned with the analysis of data sets on real organisms. [Phenetic classifications;cladistic classifications; estimatedcladograms; homoplasy; Wagner trees; Caminalcules; numerical taxonomy.] This paper,and othersto follow,takes ad- organisms.By contrastthe variousresults of vantage of the opportunityafforded by a this study merit serious attentionbecause group of artificialorganisms with a known they can be examined against the bench- phylogeny,the Caminalcules,to throwlight markof the true phylogenyof the group. on some of the questions concerningprin- The Caminalculesare artifactscreated by ciples and proceduresthat currently engage the late ProfessorJoseph H. Camin of the theattention of taxonomists.There is consid- Universityof Kansas and in effectrepresent erabledisagreement on the relativemerits of a single simulationof the evolutionarypro- pheneticand cladisticclassifications (Sneath cess by rules that have not been made ex- and Sokal, 1973;Eldredge and Cracraft,1980; plicit.However, readerswill findthat these Wiley, 1981). Some workers contend that organisms,which have the advantage over classificationsbased on phylogeneticprinci- othersimulations in presentinga visual rec- ples are empiricallybetter by variouscriteria ord to the investigator,illustrate a varietyof of optimality(Farris, 1977, 1979a,b; Micke- evolutionaryphenomena and are therefore vich,1978a, 1980; Schuh and Polhemus,1980; of considerable pedagogical and heuristic Schuh and Farris,1981). These claims have value. The relevanceof this data set to cur- been questionedby otherswho findthe evi- rentlyactive issues in systematicswill readi- dence and methodology presented to be ly becomeevident to the readerof this series. flawed(Colless, 1980;Rohlf and Sokal, 1980, I shall show thatwith respect to a substantial 1981; Sokal and Rohlf, 1981a; Rohlf et al., arrayof measurableproperties, the Camin- 1983a,b). The empiricalstudies, and the ar- alcules are well withinthe range of empiri- gumentspro and con phylogeneticclassifi- cally observed values for real taxonomic cationsderived in such investigations,suffer groupsand that,conversely, for no property froma major impediment.All of the phy- of consequence in numericaltaxonomy are logeneticclassifications reported in the lit- the Caminalcules beyond the range of ob- eratureare only estimatesof the true phy- servedvalues in real organisms. logeny, which is unknown for all real At the suggestionof the Editorand some 159 160 SYSTEMATIC ZOOLOGY VOL. 32 reviewers,this series of publicationsis ini- Ehrlichof StanfordUniversity and Dr. W. tiatedin this paper with the presentationof Wayne Moss of the Philadelphia Academy the data on which previous and succeeding of Sciences in additionto myself.The origi- studies have been based. I furnishthe im- nals drawn on the ditto mastersappear to ages of the previouslypublished 29 Recent have been lost followingthe death of Pro- species and forthe firsttime the 48 "fossil" fessorCamin in 1979. species. I also presentfor the firsttime the All examinationsof the Caminalcules for truephylogeny of the Caminalculesas gen- numericaltaxonomic studies have been car- eratedby ProfessorCamin. Withthese illus- ried out on the xeroxesof the images. Illus- trationsI providea listof the descriptionsof trationsof all 29 Recent OTUs have been charactersas adopted in my laboratoryas published three times previously (Sokal, well as a data matrixgiving the character 1966;Rohlf and Sokal, 1967;Sokal and Rohlf, statesfor all 106 charactersfor each of the 77 1980). For this purpose,inked copies of the Recent and fossilCaminalcules. In addition xeroxed images were photographed. Al- to presentinga new standardphenetic clas- thoughthe artist'scopies of the originalxe- sification,the paper describesa number of roxesare quite faithful,inevitably some fine measures for taxonomic and evolutionary detailhas been alteredor lost.Thus, not every propertiesand compares the Caminalcules characterstate describedbelow can be un- withdata setson real organismswith respect equivocallyrecognized in the featuredillus- to thesemeasures. Subsequent studies in this trations.The versionof the 29 RecentOTUs series will treatestimates of the true clado- published in Sokal (1966) was "beautified" gram,the inclusionof fossils in pheneticand by the publisher'sartist and cannotbe relied cladisticclassifications, congruence and char- upon fordetail. The images of the 48 fossils acterstability, and OTU stability. were newly inked forthis studyand all dif- ferentiatingcharacteristics can be observed ORIGIN OF THE DATA BASE in them. The original intentionin generatingthe The RecentOTUs, numbered 1 to 29, are Caminalcules was to study the nature of shown in Figure 1. The fossilOTUs, given taxonomicjudgment (eventually published differentcode names by Camin, were ran- by Sokal and Rohlf, 1980), but work with domly assigned numbers 30 to 77 by me. theseanimals has led to otherdevelopments They are shown in Figure2. in numericaltaxonomic methodology, such The truecladogram of the groupwas com- as an early method of numerical cladistics municatedto me by Camin in 1970. But al- (Camin and Sokal, 1965) and a method for though this informationwas employed in obtaining taxonomic structureby random the computationsleading to the analysis of and systematicscanning of biologicalimages taxonomicjudgment (Sokal and Rohlf,1980), (Sokal and Rohlf, 1966; Rohlf and Sokal, access to it was restrictedeven for workers 1967). Other experiments on taxonomic on this project.I did not become intimately judgmenthave also been based on the Cam- familiarwith the phylogenetictree until 1981 inalcules (Moss, 1971;Sokal, 1974;Moss and during the final analyses leading to this Hansell, 1980). manuscript. Camin drew the Caminalculesusing mas- Readers of this paper and of subsequent ter stencilsfor ditto machines. The genetic ones in this seriesshould note thatI use the continuityof the Caminalculeswas achieved -termcladogram in the sense in which I orig- by Camin by tracingsuccessive drawings of inallycoined it (Camin and Sokal, 1965;also the animals,permitting the preservationof independentlycoined with the same mean- all charactersexcept for such modifications ing by Mayr, 1965). One definitionof this as were desired.Xerox copies of the images meaning(Sneath and Sokal, 1973:29)is as "A of the RecentOTUs were made available in branching ... networkof ancestor-descen- theearly 1960s, those of the fossil OTUs some dant relationships."This definitiondiffers years later.Independent xerox copies of all fromthe several meanings attachedto the OTUs are in the possession of Dr. Paul A. termcladogram by various cladists(e.g., El- 1983 CAMINALCULES: DATA BASE 161 o u' U) C in 00. 0'~~~~~~~~~0 04~~~~~~~~~~~~4 U. U 0 0 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~1 0 0 ~~~~~~~~~~~~~~~~~~u0 U) 04 .4 0 V *0~~~~~~~~~~~~~~~ ~~~~~~~~~~*~ ~ ~ ~ ~ ~ ~ ~ K
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