Systematics and distribution of the living and fossil small barn owls of the West Indies (Aves: Strigiformes: Tytonidae).

After reviewing the systematics and distribution of the living and fossil small West Indian taxa of Tytonidae (Tyto), we reached the following conclusions: (1) Strix tuidara J. E. Gray, 1827, type locality of Brazil, is the earliest available and correct name to be used in a binomen for New World mainland barn owls; (2) the North American mainland subspecies Tyto tuidara pratincola (Bonaparte, 1838), new combination, is resident in the Bahamas ("Tyto perlatus lucayanus" Riley, 1913, is a synonym), where it probably did not colonize until after the European introduction of Rattus Fischer, in Hispaniola (Dominican Republic and Haiti) where it became established in the 20th century, and subsequently in Puerto Rico; (3) Tyto furcata (Temminck, 1827) of Cuba, Jamaica and the Cayman Islands is a different species restricted to its insular distribution, with "T. alba niveicauda" Parkes Phillips, 1978, of the Isle of Pines (now Isla de la Juventud) as a synonym; (4) the distinct species Tyto glaucops (Kaup, 1852), now endemic to Hispaniola, once occurred in Puerto Rico, as the fossil species "T. cavatica" Wetmore, 1920, is here shown to be a synonym; (5) the smallest taxon Tyto insularis (Pelzeln, 1872) of the southern Lesser Antilles is treated as a separate species, in which the nominate subspecies T. i. insularis (St. Vincent, Grenada, and the Grenadines) differs slightly but consistently in coloration from T. i. nigrescens (Lawrence, 1878) of Dominica; (6) another barn owl, Tyto maniola, new species, of this group of small tytonids from the West Indies inhabited Cuba during part of the Quaternary, and is here named and described.

Systematics and distribution of the giant fossil barn owls of the West Indies (Aves: Strigiformes: Tytonidae).

After reviewing the systematics and distribution of the extinct West Indian taxa of Tytonidae (Tyto) larger than the living barn owl Tyto alba (Scopoli), we reached the following conclusions: (1) the species T. ostologa Wetmore (1922) is the only giant barn owl known so far from Hispaniola; (2) T. pollens Wetmore (1937) was a somewhat larger and even more robust representative of T. ostologa known from the Great Bahama Bank and Cuba; (3) the very rare species T. riveroi Arredondo (1972b) is here synonymized with T. pollens; (4) the smallest taxon of these giant barn owls is T. noeli Arredondo (1972a), which is widespread and abundant in Quaternary deposits of Cuba and is here reported for the first time from two cave deposits in Jamaica; (5) the only large barn owl named so far from the Lesser Antilles is T. neddi Steadman & Hilgartner (1999), which is here synonymized with T. noeli; (6) a new taxon from Cuba, T. cravesae new species, which in size approached the linear dimensions of T. ostologa, is named and described herein.

Distinct and extinct: genetic differentiation of the Hawaiian eagle.

Eagles currently occur in the Hawaiian Islands only as vagrants, but Quaternary bones of Haliaeetus eagles have been found on three of the major islands. A previous study of a ∼3500-year-old skeleton from Maui found its mtDNA more similar to White-tailed (H. albicilla) than to Bald (H. leucocephalus) Eagles, but low intraspecific resolution of the markers and lack of comparative data from mainland populations precluded assessment of whether the individual was part of the diversity found in Eurasia, or whether it represented an endemic Hawaiian lineage. Using ancient DNA techniques, we sequenced part of the rapidly evolving mtDNA control region from the same specimen, and compared it to published range-wide control region data from White-tailed Eagles and newly generated sequences from Bald Eagles. Phylogenetic analyses indicated that the Hawaiian eagle represents a distinct (>3% divergent) mtDNA lineage most closely related to those of extant White-tailed Eagles. Based on fossil calibration, we estimate that the Hawaiian mtDNA lineage diverged from mainland sequences around the Middle Pleistocene. Although not clearly differentiated morphologically from mainland forms, the Hawaiian eagle thus likely constituted an isolated, resident population in the Hawaiian archipelago for more than 100,000 years, where it was the largest terrestrial predator.

A new species of extinct scops owl (Aves: Strigiformes: Strigidae: Otus) from São Miguel Island (Azores Archipelago, North Atlantic Ocean).

The extinct São Miguel Scops Owl Otusfrutuosoi n. sp. is described from fossil bones found in Gruta de Água de Pau, a volcanic tube in São Miguel Island (Azores Archipelago, North Atlantic Ocean). It is the first extinct bird described from the Azores and, after the Madeiran Scops Owl (O. mauli Rando, Pieper, Alcover & Olson 2012a), the second extinct species of Strigiformes known in Macaronesia. The forelimb elements of the new taxon are shorter, the hindlimb elements are longer, and the pelvis is shorter and broader than in the Eurasian Scops Owl (O. scops Linnaeus). The new species differs from O. mauli in the smaller size of many of its bones, especially the ulna and tibiotarsus. Its measurements (estimated weight, wing area, and wing loading, and the ratio of humerus + ulna + carpometacarpus length/femur length) indicate weak powers of flight and ground-dwelling habits. The latest occurrence of the new species, as evidenced by a radiocarbon date of 1970 ± 40 BP from bone collagen, indicates a Late Holocene extinction event subsequent to 49 cal BC, and was probably linked to human arrival and subsequent habitat alterations.

The bizarre wing of the Jamaican flightless ibis Xenicibis xympithecus: a unique vertebrate adaptation.

Birds have frequently evolved to exploit insular environments by becoming adapted to a terrestrial lifestyle and losing the ability to fly, usually via reducing the wings and pectoral girdle. The enigmatic flightless ibis Xenicibis xympithecus (Threskiornithidae) from the Quaternary of Jamaica provides a rare example of flight loss in ibises. We report on previously undescribed fossils of Xenicibis, and show that the wing differed radically from that of all other birds, flightless or volant. The metacarpus is elongate, grotesquely inflated and has extremely thick walls; phalanges are short and block-like; the radius is distally expanded; and the humerus is elongate. The furcula, coracoid and sternum are all well developed. We propose that the elongate forelimb and massive hand functioned in combat as a jointed club or flail. This hypothesis is supported by the morphology of the carpometacarpus, by features permitting rapid extension of the wing and by the presence of fractures in wing bones. Although other birds use the wings as weapons, none resemble Xenicibis, which represents a unique and extraordinary morphological solution to this functional problem. Xenicibis strikingly illustrates how similar selective pressures, acting on a similar starting point, can result in novel outcomes.

Predation as the primary selective force in recurrent evolution of gigantism in Poecilozonites land snails in Quaternary Bermuda.

During the last half million years, pulses of gigantism in the anagenetic lineage of land snails of the subgenus Poecilozonites on Bermuda were correlated with glacial periods when lower sea level resulted in an island nearly an order of magnitude larger than at present. During those periods, the island was colonized by large vertebrate predators that created selection pressure for large size and rapid growth in the snails. Extreme reduction in land area from rising seas, along with changes in ecological conditions at the onset of interglacial episodes, marked extinction events for large predators, after which snails reverted to much smaller size. The giant snails were identical in morphology during the last two glacials when the predators included a large flightless rail Rallus recessus (marine isotope stages (MIS) 4-2) and a crane Grus latipes and a duck Anas pachysceles (MIS 6). In a preceding glacial period (MIS 10), when the fauna also included the tortoise Hesperotestudo bermudae, the snails were not only large, but the shells were much thicker, presumably to prevent crushing by tortoises. Evolution of Poecilozonites provides an outstanding example of dramatic morphological change in response to environmental pressures in the absence of cladogenesis.

Convergent evolution of Hawaiian and Australo-Pacific honeyeaters from distant songbird ancestors.

The Hawaiian "honeyeaters," five endemic species of recently extinct, nectar-feeding songbirds in the genera Moho and Chaetoptila, looked and acted like Australasian honeyeaters (Meliphagidae), and no taxonomist since their discovery on James Cook's third voyage has classified them as anything else. We obtained DNA sequences from museum specimens of Moho and Chaetoptila collected in Hawaii 115-158 years ago. Phylogenetic analysis of these sequences supports monophyly of the two Hawaiian genera but, surprisingly, reveals that neither taxon is a meliphagid honeyeater, nor even in the same part of the songbird radiation as meliphagids. Instead, the Hawaiian species are divergent members of a passeridan group that includes deceptively dissimilar families of songbirds (Holarctic waxwings, neotropical silky flycatchers, and palm chats). Here we designate them as a new family, the Mohoidae. A nuclear-DNA rate calibration suggests that mohoids diverged from their closest living ancestor 14-17 mya, coincident with the estimated earliest arrival in Hawaii of a bird-pollinated plant lineage. Convergent evolution, the evolution of similar traits in distantly related taxa because of common selective pressures, is illustrated well by nectar-feeding birds, but the morphological, behavioral, and ecological similarity of the mohoids to the Australasian honeyeaters makes them a particularly striking example of the phenomenon.

Prevalence and diversity of avian hematozoan parasites in Asia: a regional survey.

Tissue samples from 699 birds from three regions of Asia (Myanmar, India, and South Korea) were screened for evidence of infection by avian parasites in the genera Plasmodium and Haemoproteus. Samples were collected from November 1994 to October 2004. We identified 241 infected birds (34.0%). Base-on-sequence data for the cytochrome b gene from 221 positive samples, 34 distinct lineages of Plasmodium, and 41 of Haemoproteus were detected. Parasite diversity was highest in Myanmar followed by India and South Korea. Parasite prevalence differed among regions but not among host families. There were four lineages of Plasmodium and one of Haemoproteus shared between Myanmar and India and only one lineage of Plasmodium shared between Myanmar and South Korea. No lineages were shared between India and South Korea, although an equal number of distinct lineages were recovered from each region. Migratory birds in South Korea and India originate from two different migratory flyways; therefore cross-transmission of parasite lineages may be less likely. India and Myanmar shared more host species and habitat types compared to South Korea. Comparison between low-elevation habitat in India and Myanmar showed a difference in prevalence of haematozoans.

Probable extirpation of a breeding colony of Short-tailed Albatross (Phoebastria albatrus) on Bermuda by Pleistocene sea-level rise.

Albatrosses (Diomedeidae) do not occur in the North Atlantic Ocean today except as vagrants, although five species were present in the early Pliocene. No fossil breeding sites of albatrosses were known previously. The timing of extinction of albatrosses in the North Atlantic was likewise unknown. Deposits that formed near present-day sea level along the southeastern shore of Bermuda contain remains of a former breeding colony and include intact eggshells and bones of embryos, juveniles, and adults of Short-tailed Albatross (Phoebastria albatrus), a critically endangered species now confined to a few islets in the northwestern Pacific Ocean. These deposits are correlated with the middle Pleistocene Lower Town Hill Formation, which at other sites have a radiometric age of 405,000 years ago. This equates with the marine isotope stage 11 interglacial, which culminated in a rise in sea-level to >+20 m. Bones of a juvenile Short-tailed Albatross were also found in beach deposits at +21.3 m from this same interglacial. We interpret the extirpation of albatrosses on Bermuda as probably resulting from lack of nesting sites protected from storm surges over the little emergent land that remained at the height of the marine isotope stage 11 sea level rise.

mtDNA from fossils reveals a radiation of Hawaiian geese recently derived from the Canada goose (Brantacanadensis).

Phylogenetic analysis of 1.35 kb of mtDNA sequence from fossils revealed a previously unknown radiation of Hawaiian geese, of which only one representative remains alive (the endangered Hawaiian goose or nene, Branta sandvicensis). This radiation is nested phylogenetically within a living species, the Canada goose (Branta canadensis) and is related most closely to the large-bodied lineage within that species. The barnacle goose (Branta leucopsis) is also nested within the Canada goose species and is related most closely to the small-bodied lineage of Canada geese. The peripheral isolation of the barnacle goose in the Palearctic apparently allowed the evolution of its distinctive plumage pattern, whereas the two Nearctic lineages of Canada geese share a primitive plumage pattern. The Hawaiian lineage of Canada geese diverged more dramatically, splitting into at least three species that differ in body size, body proportions, and flight ability. One fossil species, limited to the island of Hawaii, was related closely to the nene but was over four times larger, flightless, heavy-bodied and had a much more robust cranium. Application of a rate calibration to levels of DNA divergence suggests that this species evolved on the island of Hawaii in less than 500,000 years. This date is consistent with the potassium/argon-based age of the island of Hawaii of 430,000-500,000 years. The giant Hawaii goose resembles the moa-nalos, a group of massive, extinct, flightless ducks that lived on older Hawaiian Islands and thus is an example of convergent evolution of similar morphologies in island ecosystems.