. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 336 Bulletin Museum of Comparative Zoology, Vol. 151, No. 6. Figure 9. Two distinct styles of dwarfing in C. regina, producing tfie major outliers in this species. Left: two specimens from sample 765, South Caicos. Note relative thinning of these smokestack dwarfs with respect to the normal (central) specimen from sample 756, South Caicos. Right: two specimens of Sand Cay dwarfs. Note relatively squatter shells of these "double whammy" dwarfs compared with normal specimen. Leftmost dwarf is mm high. Cen
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology. 336 Bulletin Museum of Comparative Zoology, Vol. 151, No. 6. Figure 9. Two distinct styles of dwarfing in C. regina, producing tfie major outliers in this species. Left: two specimens from sample 765, South Caicos. Note relative thinning of these smokestack dwarfs with respect to the normal (central) specimen from sample 756, South Caicos. Right: two specimens of Sand Cay dwarfs. Note relatively squatter shells of these "double whammy" dwarfs compared with normal specimen. Leftmost dwarf is mm high. Central specimen is mm high. shells through the suppression of whorls that would add height without width. They therefore plot at the opposite end of axis 3, the focus for high-spired C. lewisi. This structural understanding of dwarfing and its allometries resolves two issues: first, we can interpret two apparently opposite di- rections of morphological change as dif- ferent consequences of the same triggering phenomenon; second, we can accommo- date two outlying samples as resolvable expressions of the tapering morphotype, not as taxonomic anomalies. Figure 9 por- trays the unusual morphologies of the two dwarfs. Note also (see appendix for more details), the key mean values in the two dwarfed samples for this interpretation. The subfossil smokestack has (at ) the third largest height/width ratio among South Caicos samples, and (at ) a mean whorl number only slightly below average. The Sand Cay "double whammy" has (at ) by far the squattest shell of Turks Island forms, and (at ) by far the small- est number of whorls. B) Covariances of the Tapering Morphospace The three axes of Figure 7 include of all information, distributed as on axis 1, on axis 2, and on axis 3. Table 4 presents the matrix of factor scores. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability
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