
Caribbean Journal of Science, Vol. 26, No. 1-2, 31-44, 1990 Copyright 1990 College of Arts and Sciences University of Puerto Rico, Mayaguez The Jamaican Radiation of Anolis (Sauria: Iguanidae): An Analysis of Relationships and Biogeography Using Sequential Electrophoresis S. BLAIR H EDGES AND KRISTI L. BURNELL Department of Zoology, University of Maryland, College Park, Maryland 207421 ABSTRACT. – The relationships of the six native species of Jamaican Anolis and five additional West Indian species were examined by sequential starch gel electrophoresis at 28 loci. The protein data are in agreement with published albumin immunological data supporting the monophyly of the native Jamaican species. These six species and one from the Cayman Islands (conspersus) form the grahami series. Our protein data support the recognition of three species groups within this series: the grahami group (garmani, grahami, and opalinus), the lineatopus group (lineatopus and reconditus), and the valencienni group (valencienni). Although not examined here, conspersus is included in the grahami group based on mor- phology. The biogeographic history of Jamaican Anolis is placed in a geological time frame with the use of the molecular clock. Colonization of Jamaica probably occurred in the mid Miocene (14 mya). Most speciation within the radiation apparently occurred during the Pliocene and may have been associated with sea level fluctuations. Although the Jamaican species have converged with species on other islands, there is little evidence of morphological and ecological convergence within the radiation. Lizards of the genus Anolis are widely Jamaican Anolis: An Island Radiation? distributed in the West Indies, numbering There are six native and one introduced over 130 species (Schwartz and Hender- species of Anolis on Jamaica. The latter, sa- son, 1988). Recently, their relationships and grei, is a Cuban species that likely was in- classification have been the topic of debate. troduced by man based upon its rapid range Guyer and Savage (1986) divided the genus expansion in Jamaica (Underwood and into multiple genera based on a reanalysis Williams, 1959; Williams, 1969; pers. ohs.). of some published data sets. However, se- Five of the native species are islandwide rious errors and confusions in this reanal- in distribution whereas the sixth, recondi- ysis led Cannatella and de Queiroz (1989) tus, is restricted to the Blue Mountains in and Williams (1989) to reject that revised eastern Jamaica. classification. Our recent electrophoretic The ecology and behavior of Jamaican study of 49 West Indian Anolis using slow- Anolis have been well-studied (Rand, 1967a, evolving loci (Burnell and Hedges, 1990) b; Schoener and Schoener, 1971; Hicks, partially supported Williams’ (1976) clas- 1973; Trivers, 1976; Jenssen, 1977; Hicks sification at lower levels (species groups and Trivers, 1983). However, little atten- and series) but not at higher levels (sec- tion has been given to the relationships tions and subsections). We revised that and biogeography of this anole fauna. The classification and recognized 21 series of first discussion of relationships was by Un- West Indian Anolis. One of those is the gra- derwood and Williams (1959), who contin- hami series, which includes all native Ja- ued the recognition of valencienni as a sep- maican species and one in the Cayman Is- arate genus (Xiphocercus) that included lands. darlingtoni of Hispaniola. Both are relative- ly large, cryptic species with some simi- larities in pattern, scalation, and behavior. 1Current address: Department of Biology, 208 Of the remaining five species, grahami and Mueller Lab, Penn State University, University Park, opalinus were placed in the grahami group, Pennsylvania 16802 (SBH); and Department of Bio- logical Sciences, University of California, Santa Bar- lineatopus and reconditus in the lineatopus bara, California 93106 (KLB). group, and garmani in the garmani group. 31 32 S. B. HEDGES AND K. L. BURNELL Several geographic variants of grahami and due to allelic convergence with members lineatopus were recognized as subspecies, of the grahami series. In that study, 12 slow- and they suggested that each of the three evolving loci and sequential electropho- groups on Jamaica was part of a more resis were used to elucidate clusters of widely distributed group of Anolis. species (species groups and series). In this Williams’ (1976) formal classification of study, we focus on the relationships of the West Indian anoles, based largely on the Jamaican species using an expanded data osteological study of Etheridge (1960), did set (28 slow- and fast-evolving loci) in an not recognize the genus Xiphocercus and effort to resolve their relationships and test instead placed valencienni with sagrei (and the hypothesis that they form a single is- other Cuban species) in the sagrei series of land radiation. The technique of sequential Anolis. The five remaining Jamaican species electrophoresis (Coyne, 1982) again is used and conspersus from the Cayman Islands in order to uncover hidden alleles and ob- were placed in a single series (grahami) and tain a more robust estimate of phylogeny. species group (grahami). For comparison, we also present an esti- Shochat and Dessauer (1981) presented mate of relationships based on an analysis albumin immunological distances for the of published morphological data. Jamaican species. Despite the limited scope of their comparative data set (only two Cu- M ATERIALS AND M ETHODS ban and two Hispaniolan species were ex- Protein variation in 11 species of West amined), low distances (8-15) among Ja- Indian Anolis was examined at 28 genetic maican species and higher distances (19- loci. Lizards were collected in the field from 67) to species from other islands suggested 1983 to 1987 (localities and sample sizes that all six native Jamaican Anolis form a are given in Appendix 1). All six native monophyletic group. However, because Jamaican species and a Jamaican popula- only one Jamaican species (valencienni) was tion of sagrei were obtained. Four addi- represented by an antiserum, the relation- tional species (carolinensis, cristatellus, cy- ships among those six species could not be botes, and darlingtoni) were included for resolved. comparison and to provide rooting for the Chromosome data now are available for parsimony tree. In the case of one Jamaican over 80 species of Anolis (German, 1973; species, valencienni, two populations were Peccinini-Scale, 1981; Hedges and Hass, examined: one from the interior of the is- unpubl.) and species in the grahami series land (Cockpit Country) and the other from stand out in sharing an uncommon num- the isolated Portland Ridge peninsula. The ber, 2N = 30 (although previously unre- latter population, which exhibits some ported, the diploid number of reconditus is morphological differences, was included 30; Hass and Hedges, unpubl. data). How- to assess its taxonomic status. Preserved ever, the situation is complex, with at least voucher specimens are deposited in the grahami (and apparently opalinus) having United States National Museum of Natural considerable intraspecific variation in History (USNM) and Museum of Compar- chromosome number (30-37; Blake, 1986). ative Zoology (MCZ). Also, conspersus, and possibly opalinus, are Tissue samples (heart, liver, kidney and sexually heteromorphic (German and At- leg muscle) were prepared for electropho- kins, 1966, 1968; German, 1973). Presently, resis following the methods of Hedges the karyotypic data provide insufficient in- (1986, 1989a). Horizontal starch gel elec- formation on the relationships of the Ja- trophoresis was employed using Con- maican species. naught starch and sucrose at concentra- In our recent electrophoretic study of tions of 12.5% and 7.5%, respectively. West Indian Anolis (Burnell and Hedges, Buffers were prepared following the meth- 1990), all six native Jamaican species (gra- ods of Selander et al. (1971). The primary hami series) and sagrei formed a group. variable chosen for sequential electropho- However, examination of the data revealed resis was buffer type and no more than four that sagrei likely was misplaced on the tree conditions were used with each locus (see RELATIONSHIPS OF JAMAICAN ANOLIS 33 TABLE 1. Protein loci and electrophoretic conditions. Electrophoretic Enzyme conditions Commission Protein Locus Number a 1234 Stain c Acid phosphatase Acp 3.1.3.2 5 5 Aconitate hydratase Acon-l 4.2.1.3 12 2 Aconitate hydratase Acon-2 4.2.1.3 12 2 Adenylate kinase Ak 2.7.4.3 12 1 Aspartate aminotransferase Aat 2.6.1.1 5 3 Creatine kinase Ck-2 2.7.3.2 6 2 Cytochrome b5 reductase Cr 1.6.2.2 1 2 Dipeptidase (dl-leucyl-dl-alanine) Dpep 3.4.13.11 15 5 Fumarate hydratase Fh 4.2.1.2 3 2 Glucose-6-phosphate isomerase Gpi 5.3.1.9 547 3 Glycerol-3-phosphate dehydrogenase Gpd 1.1.1.8 5 3 Lactate dehydrogenase Ldh-1 1.1.1.27 31 5 Lactate dehydrogenase Ldh-2 1.1.1.27 3127 5 Lactoyl-glutathione lyase Lgl 4.4.1.5 63 2 Malate dehydrogenase Mdh 1.1.1.37 1 5 Malate dehydrogenase (NADP) Me 1.1.1.40 45 4 Mannosephosphate isomerase Mpi-1 5.3.1.8 45 4 Mannosephosphate isomerase Mpi-2 5.3.1.8 45 4 Phosphoglucomutase Pgm-1 2.7.5.1 12 3 Phosphoglucomutase Pgm-2 2.7.5.1 12 3 Phosphoglucomutase Pgm-3 2.7.5.1 1235 3 Phosphogluconate dehydrogenase Pgd 1.1.1.44 51 3 Protein 1 Pt-1 — 432 5 Protein 2 Pt-2 — 412 5 Protein 3 Pt-3 — 46 5 Pyruvate kinase Pk 2.7.1.40 51 1 Tripeptidase (leu-gly-gly) Tpep 3.4.13.11 15 5 Xanthine dehydrogenase Xdh 1.2.1.37 563 5 a Nomenclature Committee of the International Union of Biochemistry (1984). b (1) Tris-citrate pH 8.0, 130 v, 6 h; (2) Tris-citrate pH 6.7, 150 v, 6 h; (3) Poulik, 300 v, ca. 5.5 h; (4) Lithium hydroxide, 350 v, ca.
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