The adaptive genomic landscape of beak morphology in Darwin's finches.

Beak shape in Darwin's ground finches (Geospiza) is emblematic of natural selection and adaptive radiation, yet our understanding of the genetic basis of beak shape variation, and thus the genetic target of natural selection, is still evolving. Here we reveal the genomic architecture of beak shape variation using genomewide comparisons of four closely related and hybridizing species across 13 islands subject to parallel natural selection. Pairwise contrasts among species were used to identify a large number of genomic loci that are consistently related to species differences across a complex landscape.

GEneSTATION 1.0: a synthetic resource of diverse evolutionary and functional genomic data for studying the evolution of pregnancy-associated tissues and phenotypes.

Mammalian gestation and pregnancy are fast evolving processes that involve the interaction of the fetal, maternal and paternal genomes. Version 1.0 of the GEneSTATION database (http://genestation.

The evolutionary history of Darwin's finches: speciation, gene flow, and introgression in a fragmented landscape.

Many classic examples of adaptive radiations take place within fragmented systems such as islands or mountains, but the roles of mosaic landscapes and variable gene flow in facilitating species diversification is poorly understood. Here we combine phylogenetic and landscape genetic approaches to understand diversification in Darwin's finches, a model adaptive radiation. We combined sequence data from 14 nuclear introns, mitochondrial markers, and microsatellite variation from 51 populations of all 15 recognized species.

Multimodal dispersal during the range expansion of the tropical house gecko Hemidactylus mabouia.

Dispersal influences both the ecological and evolutionary dynamics of range expansion. While some studies have demonstrated a role for human-mediated dispersal during invasion, the genetic effects of such dispersal remain to be understood, particularly in terrestrial range expansions. In this study, we investigated multimodal dispersal during the range expansion of the invasive gecko Hemidactylus mabouia in Florida using 12 microsatellite loci.

Fine-scale genetic structure arises during range expansion of an invasive gecko.

Processes of range expansion are increasingly important in light of current concerns about invasive species and range shifts due to climate change. Theoretical studies suggest that genetic structuring may occur during range expansion. Ephemeral genetic structure can have important evolutionary implications, such as propagating genetic changes along the wave front of expansion, yet few studies have shown evidence of such structure.

A century of genetic change and metapopulation dynamics in the Galápagos warbler finches (Certhidea).

Populations that are connected by immigrants play an important role in evolutionary and conservation biology, yet we have little direct evidence of how such metapopulations change genetically over evolutionary time. We compared historic (1894-1906) to modern (1988-2006) genetic variation in 11 populations of warbler finches at 14 microsatellite loci. Although several lines of evidence suggest that Darwin's finches may be in decline, we found that the genetic diversity of warbler finches has not generally declined, and broad-scale patterns of variation remained similar over time.

110 years of Avipoxvirus in the Galapagos Islands.

The role of disease in regulating populations is controversial, partly owing to the absence of good disease records in historic wildlife populations. We examined birds collected in the Galapagos Islands between 1891 and 1906 that are currently held at the California Academy of Sciences and the Zoologisches Staatssammlung Muenchen, including 3973 specimens representing species from two well-studied families of endemic passerine birds: finches and mockingbirds. Beginning with samples collected in 1899, we observed cutaneous lesions consistent with Avipoxvirus on 226 (6.

Evolutionary dead end in the Galápagos: divergence of sexual signals in the rarest of Darwin's finches.

Understanding the mechanisms underlying speciation remains a challenge in evolutionary biology. The adaptive radiation of Darwin's finches is a prime example of species formation, and their study has revealed many important insights into evolutionary processes. Here, we report striking differences in mating signals (songs), morphology and genetics between the two remnant populations of Darwin's mangrove finch Camarhynchus heliobates, one of the rarest species in the world.

Multilocus genotypes from Charles Darwin's finches: biodiversity lost since the voyage of the Beagle.

Genetic analysis of museum specimens offers a direct window into a past that can predate the loss of extinct forms. We genotyped 18 Galápagos finches collected by Charles Darwin and companions during the voyage of the Beagle in 1835, and 22 specimens collected in 1901. Our goals were to determine if significant genetic diversity has been lost since the Beagle voyage and to determine the genetic source of specimens for which the collection locale was not recorded.

Isolation and characterization of 12 polymorphic microsatellite markers in the tropical house gecko (Hemidactylus mabouia).

We present 12 variable microsatellite loci isolated from the invasive tropical house gecko, Hemidactylus mabouia. Polymerase chain reaction (PCR) primers were tested on 39 individuals from two locations in Miami, Florida. Heterozygote deficiency was detected for four loci, and we attribute this to possible null alleles or population substructure.

Colonization and diversification of Galápagos terrestrial fauna: a phylogenetic and biogeographical synthesis.

Remote oceanic islands have long been recognized as natural models for the study of evolutionary processes involved in diversification. Their remoteness provides opportunities for isolation and divergence of populations, which make islands remarkable settings for the study of diversification. Groups of islands may share a relatively similar geological history and comparable climate, but their inhabitants experience subtly different environments and have distinct evolutionary histories, offering the potential for comparative studies.

Habitat selection and ecological speciation in Galápagos warbler finches (Certhidea olivacea and Certhidea fusca).

We investigated phylogeographic divergence among populations of Galápagos warble finches. Their broad distribution, lack of phenotypic differentiation and low levels of genetic divergence make warbler finches an appropriate model to study speciation in allopatry. A positive relationship between genetic and geographical distance is expected for island taxa.

Inbreeding and interbreeding in Darwin's finches.

Studies of inbreeding and interspecific hybridization are generally pursued separately with different metrics. There is a need to integrate them because they have the common goal of seeking an understanding of the genetic and ecological basis of fitness variation in populations. We use mean expected heterozygosity as an axis of variation on which to compare the fitness of inbreeding and hybridizing Darwin's finches (Geospiza scandens and G.

Environmental conditions affect the magnitude of inbreeding depression in survival of Darwin's finches.

Understanding the fitness consequences of inbreeding (inbreeding depression) is of importance to evolutionary and conservation biology. There is ample evidence for inbreeding depression in captivity, and data from wild populations are accumulating. However, we still lack a good quantitative understanding of inbreeding depression and what influences its magnitude in natural populations.

An experimental investigation of the competitive displacement of a native gecko by an invading gecko: no role for parasites.

On islands across the Pacific the invasion of the gecko Hemidactylusfrenatus has caused a decline in the abundance of a resident gecko, Lepidodactyluslugubris. In a previous study we demonstrated that the prevalence of the cestode Cylindrotaenia sp. is higher in the resident gecko on islands where it is sympatric with the invader than on islands where it occurs alone.

A PHYLOGENETIC ANALYSIS OF BODY SIZE EVOLUTION AND BIOGEOGRAPHY IN CHUCKWALLAS (SAUROMALUS) AND OTHER IGUANINES.

The evolution of body size was reconstructed in chuckwallas (genus Sauromalus), large herbivorous lizards of southwest North America, using a phylogeny derived from sequence variation in the mitochondrial cytochrome b gene. The body mass of two endemic island species (S. hispidus and S.