War of the Iguanas: Conflicting Molecular and Morphological Phylogenies and Long-Branch Attraction in Iguanid Lizards

Wiens, John J.; Hollingsworth, Bradford D.

doi:10.1080/10635150050207447

Cited by 113 publications

(103 citation statements)

References 78 publications

(88 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For MP and ML, nodal support was tested by bootstrapping (29), with 1,000 pseudoreplicates. A. cristatus, the sister taxon of Conolophus (30), was used as an outgroup within the Iguaninae group. Alternative tree topologies were investigated using the S-H test (31).…”

Section: Methodsmentioning

confidence: 99%

An overlooked pink species of land iguana in the Galápagos

Gentile

Fabiani

Márquez

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Despite the attention given to them, the Galápagos have not yet finished offering evolutionary novelties. When Darwin visited the Galápagos, he observed both marine (Amblyrhynchus) and land (Conolophus) iguanas but did not encounter a rare pink blackstriped land iguana (herein referred to as ''rosada,'' meaning ''pink'' in Spanish), which, surprisingly, remained unseen until 1986. Here, we show that substantial genetic isolation exists between the rosada and syntopic yellow forms and that the rosada is basal to extant taxonomically recognized Galápagos land iguanas. The rosada, whose present distribution is a conundrum, is a relict lineage whose origin dates back to a period when at least some of the present-day islands had not yet formed. So far, this species is the only evidence of ancient diversification along the Galápagos land iguana lineage and documents one of the oldest events of divergence ever recorded in the Galápagos. Conservation efforts are needed to prevent this form, identified by us as a good species, from extinction.genetic isolation ͉ molecular phylogeny ͉ evolution ͉ islands ͉ lizards S ince Darwin's pioneering work in the archipelago, the Galápagos Islands have been a major scientific resource for evolutionary biologists. This archipelago, currently consisting of about a dozen volcanic islands and more than 100 associated islets, is located on the equator, about 1,000 kilometers west of the South-American coast (Fig. 1). Given their volcanic origin, the Galápagos Islands host unique flora and fauna that have evolved over millions of years in geographic isolation, generating a variety of endemic species with unique and varied ecological, morphological, and behavioral adaptations (1, 2).Land iguanas are among the most spectacular representative species of the Galápagos Islands. They once lived in many areas of the Galápagos archipelago (Fig. 1). Currently, many factors contribute to their threatened status (3), one of which may be incomplete taxonomy (4). Two species of Galápagos land iguanas are currently recognized: Conolophus pallidus and Conolophus subcristatus, with the former occurring only on Santa Fe, whereas C. subcristatus occurs on Fernandina, Isabela, Santa Cruz, Plaza Sur, Seymour Norte (a translocated population), and Baltra.Charles Darwin visited the Galápagos in 1835. During the 5 weeks of his stay in the archipelago, he did not explore Volcan Wolf (the northernmost volcano in Isabela). Thus, although he noticed and commented on both marine and land iguanas (5), he did not encounter a distinct form of land iguana that occurs only on that volcano. Perhaps even more surprising, this form (herein referred to as ''rosada,'' † meaning ''pink'' in Spanish) remained unrecorded despite many other scientists having visited Volcan Wolf over the past century. Since it was accidentally seen by some Galápagos National Park rangers in 1986, this form has received no attention. The rosada form is characterized by a distinct phenotype (Fig. 2). It can be clearly distinguished from the syntopic...

show abstract

Section: Methodsmentioning

confidence: 99%

An overlooked pink species of land iguana in the Galápagos

Gentile

Fabiani

Márquez

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…In fact, common objections to the use of many morphological characters on the basis of their being highly polymorphic or continuous may not be warranted. For example, Wiens and Hollingsworth (2000) and Smith and Gutberlet (2001) have shown that even highly polymorphic characters can contribute positively to cladistic structure. Furthermore, although continuously variable characters are generally excluded (Pimentel and Riggins 1987;Cranston and Humphries 1988) or variously recoded as categorical in phylogenetic analyses (Archie 1985;Thiele 1993;Rae 1998), there is no compelling reason for their exclusion or their coding into discrete states (Farris 1970;Felsenstein 1988).…”

Section: On Resolving Species-level Phylogeniesmentioning

confidence: 99%

A Phylogeny for the African Restionaceae and New Perspectives on Morphology’s Role in Generating Complete Species Phylogenies for Large Clades

Hardy¹,

Moline

Linder

2008

International Journal of Plant Sciences

View full text Add to dashboard Cite

Hardy, C R; Moline, P ; Linder, H P Hardy, C R; Moline, P; Linder, H P (2008 Difficulties with obtaining complete species-level phylogenies include (1) the accurate identification and sampling of species, (2) obtaining a complete species sampling, and (3) resolving relationships among closely related species.We addressed these in a study of 317 species and subspecies of the African Restionaceae. Accurate species identification and collection in the field was facilitated by a morphology-based interactive key to all species. Despite intensive fieldwork, however, material for DNA extraction could not be obtained for 20 of the 292 species of the focal Restio subclade. Furthermore, the 6831 aligned nucleotides and 1685 parsimonyinformative sequence characters were insufficient to resolve relationships fully within the clade. A simulation indicated that an additional 5000-7000 bases may have been needed to achieve supported resolution in the neighborhood of 95%-100%. Instead of further sequencing, we investigated the phylogenetic utility of the large set of characters contained within the interactive key data set, exploiting recent advances in parsimony and Bayesian programs that allow multistate and supermultistate (including continuous for parsimony) morphological characters. On doing so, parsimony resolution increased 17% to nearly 100%, and overall support increased in both parsimony (bootstrap) and Bayesian (posterior probability) frameworks. Taxa for which DNA data were lacking could be placed in fully resolved positions. Experiments using the parsimony ratchet indicated that placement of these morphology-only taxa may have been completely accurate 30% of the time, to within three nodes of accuracy 60% of time, and accurate to genus 96% of the time. Accurate placement of morphology-only taxa through Bayesian analysis may require extensive effort devoted toward exploring tree and parameter space. We conclude that the increasingly available large morphological data sets associated with interactive keys or informatics initiatives represent convenient yet potentially powerful tools in overcoming many of the commonly encountered obstacles in molecular-based species-level phylogenetics. Difficulties with obtaining complete species-level phylogenies include (1) the accurate identification and sampling of species, (2) obtaining a complete species sampling, and (3) resolving relationships among closely related species. We addressed these in a study of 317 species and subspecies of the African Restionaceae. Accurate species identification and collection in the field was facilitated by a morphology-based interactive key to all species. Despite intensive fieldwork, however, material for DNA extraction could not be obtained for 20 of the 292 species of the focal Restio subclade. Furthermore, the 6831 aligned nucleotides and 1685 parsimonyinformative sequence characters were insufficient to resolve relationships fully within the clade. A simulation indicated that an additional 5000-7000 bases may have been needed to achieve s...

show abstract

“…The large-scale tree topology follows Estes et al (1988), rather than the single-gene-based analysis of Harris et al (1999). Within Iguania, we followed the family-rich nomenclature of Frost and Etheridge (1989), although some relationships were clarified by Wiens and Hollingsworth (2000) [iguanids (e.g. Dipsosaurus) basal within Iguania], Schulte et al (1998; agamid placement within Iguania) and Macey et al (1997; crotaphytids sister to phrynosomatids).…”

Section: Phylogenymentioning

confidence: 99%

Muscle fiber-type variation in lizards (Squamata) and phylogenetic reconstruction of hypothesized ancestral states

Bonine

Gleeson

Garland

2005

Journal of Experimental Biology

View full text Add to dashboard Cite

Previously, we found that phrynosomatid lizards, a diverse group common in the southwestern USA, vary markedly in fiber-type composition of the iliofibularis (a hindlimb muscle important in locomotion). Phrynosomatidae comprises three subclades: the closely related sand and horned lizards, and their relatives the Sceloporus group. The variation in muscle fiber-type composition for 11 phrynosomatid species is attributable mainly to differences between the sand-and horned-lizard subclades. Here, we expand the phrynosomatid database with three additional species and compare these results with data collected for 10 outgroup (distantly related) species. Our goal was to determine if the patterns found in Phrynosomatidae hold across a broader phylogenetic range of the extant lizards and to elucidate the evolution of muscle fiber-type composition and related traits. To allow for meaningful comparisons, data were collected from species that are primarily terrestrial and relatively small in size (3.5-65·g body mass). Results indicate that the fiber-type variation observed within the Phrynosomatidae almost spans the range of variation observed in our sample of 24 species from eight families.However, one species of Acanthodactylus (Lacertidae) had a consistent region of large tonic fibers (that did not stain darkly for either succinic dehydrogenase or myosin ATPase activity), a fiber-type only occasionally seen in the other 23 species examined. Many species have a large proportion of either fast-twitch glycolytic (FG; e.g. sand lizards and Aspidoscelis) or fast-twitch oxidative-glycolytic (FOG) fibers (e.g. horned lizards), with the slow-oxidative proportion occupying only 1-17% of the iliofibularis. Importantly, the negative relationship between FG and FOG composition observed in Phrynosomatidae appears to be a characteristic of lizards in general, and could lead to functional trade-offs in aspects of locomotor performance, as has previously been reported for Lacertidae. Reconstruction of ancestral trait values by use of phylogenetically based statistical methods indicates especially large changes in fiber-type composition during the evolution of horned lizards.

show abstract

War of the Iguanas: Conflicting Molecular and Morphological Phylogenies and Long-Branch Attraction in Iguanid Lizards

Cited by 113 publications

References 78 publications

An overlooked pink species of land iguana in the Galápagos

An overlooked pink species of land iguana in the Galápagos

A Phylogeny for the African Restionaceae and New Perspectives on Morphology’s Role in Generating Complete Species Phylogenies for Large Clades

Muscle fiber-type variation in lizards (Squamata) and phylogenetic reconstruction of hypothesized ancestral states

Contact Info

Product

Resources

About