Fruit Pigeons Research Articles

Species coexistence by wide constant size spacing

We consider the distribution of fruit pigeons of the genera Ptilinopus and Ducula on the island of New Guinea. Of the 21 species, between six and eight coexist inside humid lowland forests. We conducted or analyzed 31 surveys at 16 different sites, resurveying some sites in different years. The species coexisting at any single site in a single year are a highly nonrandom selection of the species to which that site is geographically accessible. Their sizes are both much more widely spread and more uniformly spaced than in random sets of species drawn from the locally available species pool. We also present a detailed case study of a highly mobile species that has been recorded on every ornithologically explored island in the West Papuan island group west of New Guinea. That species' rareness on just three well-surveyed islands within the group cannot be due to an inability to reach them. Instead, its local status decreases from abundant resident to rare vagrant in parallel with increasing weight proximity of the other resident species.

What determines the basal rate of metabolism?

The basal rate of metabolism (BMR) is the most reported estimate of energy expenditure in endotherms. Its principal determinant is body mass, but BMR also correlates with a variety of behavioral and ecological factors that do not determine basal rate: they are byproducts of the mechanisms that are its determinate. In mammals, mass-independent BMR increases when muscle mass is >40% of total body mass and BMR is then ≥100% of the value expected from body mass. Mammals with muscle masses <30% of body mass have lower BMRs, a diminished capacity to regulate body temperature and often have reduced activity levels. At muscle masses <42% of body mass, birds have body temperatures and basal rates higher than mammals with the same muscle mass. Their high basal rates derive from fast blood flow and increased mitochondrial density in their pectoral muscles. These enhancements also occur in the flight muscles of bats. Oxygen transport to the pectoral muscles of birds is facilitated by an increase in heart mass and hematocrit. This arrangement avoids transporting a large muscle mass to fuel flight, thereby reducing the cost of flight. Pectoral muscle masses <9% of body mass correlate with a flightless condition in kiwis, rails and ducks but some fruit pigeons have BMRs as low as those measured in kiwis, while remaining volant. The mass-independent BMRs of endotherms principally reflect changes of muscle activity and mass. An increase in muscle mass may have contributed to the evolution of endothermy.

Out of Australia and back again: the world-wide historical biogeography of non-pollinating fig wasps (Hymenoptera: Sycophaginae)

Aim Figs (Ficus, Moraceae) are exploited by rich communities of often host-specific phytophagous wasps. Among them, gall-inducing Sycophaginae (Hymenoptera, Chalcidoidea) may share a common history with Ficus and their mutualistic pollinators (Agaonidae). We investigate here, for the first time, the phylogeny and biogeographical history of Sycophaginae and compare the timing of radiation and dispersion of major clades with available data on Ficus and fig pollinators. Reconstructing the history of their host colonization and association over space and time is central to understanding how fig wasp communities were assembled. Location World-wide. Methods Maximum likelihood and Bayesian analyses were conducted on 4267 bp of mitochondrial and nuclear DNA to produce a phylogeny of all genera of Sycophaginae. Two relaxed clock methods with or without rate autocorrelation were used for date estimation. Analyses of ancestral area were also conducted to investigate the geographical origin of the Sycophaginae. Results The phylogeny is well resolved and supported. Our data suggest a post-Gondwanan origin for the Sycophaginae (50–40 Ma) and two independent out-of-Australia dispersal events to continental Asia. Given palaeoclimatic and palaeogeographic records, the following scenario appears the most likely. The ancestor of Idarnes+Apocryptophagus migrated to Greater India through the Ninetyeast Ridge (40–30 Ma). The ancestor of Anidarnes+Conidarnes dispersed later via Sundaland (25–20 Ma). Idarnes and Anidarnes subsequently reached the New World via the North Atlantic land bridges during the Late Oligocene Warming Event. Apocryptophagus reached Africa c. 20 Ma via the Arabic corridors and returned to Australasia following the expansion of Sundaland tropical forests (20–10 Ma). Main conclusions Sycophaginae probably invaded the fig microcosm in Australia c. 50–40 Ma after the origin of their host plant. Once associated with figs, they dispersed out of Australia and radiated together with their host fig and associated pollinator through the tropics. We recorded a good coincidence of timing between dispersal events of Sycophaginae and continental connections. Furthermore, fruit pigeons that disperse figs probably spread out of Australasia through the Indian Ocean via the Ninetyeast Ridge c. 38 Ma. Therefore, our study highlights the potential for combining molecular phylogenetics with multiple methods of dating of interacting groups to reconstruct the historical biogeography of plant–herbivore associations.

Seed Dispersal Distances and Plant Migration Potential in Tropical East Asia

ABSTRACTMost predictions of vegetation responses to anthropogenic climate change over the next 100 yr are based on plant physiological tolerances and do not account for the ability of plant species to migrate over the distances required in the time available, or the impact of habitat fragmentation on this ability. This review assesses the maximum routine dispersal distances achievable in tropical East Asia and their vulnerability to human impacts. Estimates for various plant–vector combinations range from &lt; 10 m, for species dispersed by ants or mechanical means, to &gt; 10 km for some species dispersed by wind (tiny seeds), water, fruit pigeons, large fruit bats (tiny seeds), elephants, rhinoceroses, and people. Most plant species probably have maximum dispersal distances in the 100–1000 m range, but the widespread, canopy‐dominant Dipterocarpaceae and Fagaceae are normally dispersed &lt; 100 m. Large fruit bats and fruit pigeons are particularly important for long‐distance dispersal in fragmented landscapes and should be protected from hunting. The maximum seed dispersal distances estimated in this study are potentially sufficient for many plant species to track temperature changes in steep topography, but are far too small for a significant role in mitigating climate change impacts in the lowlands, where temperature and rainfall gradients are much more shallow.

A Large Fruit Pigeon (Columbidae) from the Early Miocene of New Zealand

ABSTRACT. We describe a new genus and species of pigeon (Columbiformes) from a single coracoid from the St Bathans Fauna of New Zealand (16–19 mya). It is the first columbid species described from pre-Pliocene deposits in Australasia. Two apomorphies identify the fossil as belonging to the ptilinopine group of fruit pigeons, among which it is most similar to Hemiphaga, the large fruit pigeon currently endemic to the New Zealand biogeographic area. This reveals that the Hemiphaga lineage has been in New Zealand since the Early Miocene, which supports recent divergence-date estimates for Hemiphaga and its modern sister taxon (Lopholaimus) based on molecular data.

Sample size and the estimation of physiological parameters in the field

Summary Estimates of basal rate of metabolism in fruit pigeons and flying foxes, derived from the mean of individual means, were compared to the mean basal rate obtained by pooling all data into a single estimate. Pooled estimates of basal rate differ by ≤1% of the basal rates obtained from the mean of individual means in 7 of 10 species of pigeons and 4 of 11 species of flying foxes. The coefficient of variation of the mean of individual mean basal rates decreased with an increase in the mean number of measurements per individual, which, given that the number of measurements per individual was 8·4 in pigeons and 3·8 in flying foxes, partially accounts for the smaller coefficients in pigeons. The maximal absolute difference between individual mean basal rates and the mean of individual means within a species decreased with an increase in the number of measurements per individual to 8, beyond which the difference remained constant. Repeated measurements on a single individual usually gave an estimate of basal rate within 2–8% of the species’ mean when eight or more measurements were made. . The analysis of limited samples most often occurs in the study of elusive or endangered species, when the availability of individuals for study is greatly limited.

Interactions among Frugivores and Fleshy Fruit Trees in a Philippine Submontane Rainforest

Abstract: We assessed the potential effect of frugivore extinctions on forest regeneration in the North Negros Forest Reserve, a forest fragment that is one of the last remaining wet tropical rainforest ecosystems in the biogeographic region of the central Philippine Islands. We evaluated foraging observations of 19 species of birds, fruit bats, and other mammals in three successional habitats and identified tree species that are potentially at risk because their seeds are dispersed by frugivores that are seriously endangered. The relative abundance of zoochorous trees in this forest community was exceptionally high (80%), suggesting that the process of forest regeneration will change drastically if endangered frugivores are hunted to extinction. We grouped 45 tree species as early‐, mid‐, or late‐successional species based on their population structure and we demonstrated that early‐successional tree species were visited by a wide spectrum of frugivores, whereas mid‐ and late‐successional species were visited mostly by hornbills (Bucerotidae) and fruit pigeons (Columbidae). Late‐successional tree species were most specialized with respect to dispersers and could therefore be susceptible to extinction. We recommend tree species that could be useful for assisted natural regeneration projects in the reserve because they are visited by a variety of frugivores. Of those, we recommend early‐successional trees for open‐field plantations and mid‐successional tree species for enrichment plantings.

Effects of Tropical Cyclones Ofa and Val on the Structure of a Samoan Lowland Rain Forest

In February 1990, tropical cyclone Ofa struck Western Samoa with very strong winds (in excess of 200 km/hr). In December 1991, less than 22 months later, tropical cyclone Val struck the same area with similar intensity. In the moist lowland forest of the Tafua Rain Forest Reserve, Savai'i, Western Samoa, we examined the effects of the two cydones on forest structure, tree mortality, and interspecific differences in damage. Average mortality of trees was high after both cyclones (28% and 33%, respectively). In one forest area, subject to a fire after the first storm, mortality was more than 90 percent. The frequency of uprooted trees was 3 1 percent after Ofa, but only 16 percent after Val. Uprooting was significantly more frequent among species lacking buttresses or stilt roots. As a combined effect of the two cyclones, the lowland forest of Tafua suffered a 53 percent tree mortality, with remaining standing trees being severely damaged (topped and with a substantial reduction of main branches). Average tree density dropped from an estimated 476 trees/ha (>5 cm DBH), before Ofa to 225 trees/ha after Val. Existent gap sizes are reflected by the changes in mean canopy cover which decreased from nearly 100 percent before Ofa to 27 percent after Val. Post-cyclone recovery is often observed to be very rapid, but the very large gaps created in the Tafua forest and the simultaneous loss of the whole guild of vertebrate seed dispersers (flying foxes and fruit pigeons) suggests it will be a long time before the upper canopy is once again closed.

Biliary bile acids of fruit pigeons and doves (Columbiformes): presence of 1-beta-hydroxychenodeoxycholic acid and conjugation with glycine as well as taurine.

The biliary bile acid composition of 30 species of pigeons and doves belonging to seven genera in the avian order Columbiformes was determined using TLC, HPLC, GLC/MS, LSIMS, and NMR. In 23 of 25 species of fruit pigeons and doves, chenodeoxycholic acid was the major bile acid (> 50%). In only 1 species (Ptilinopus ornatus) was cholic the major bile acid. A number of species (7 of 15 species in the genus Ptilinopus, and 6 of 9 species in the genus Ducula) contained 1 beta,3 alpha,7 alpha-trihydroxy-5 beta-cholan-24-oic acid in proportions ranging from 2 to 43%. This 1 beta-hydroxy derivative of chenodeoxycholic acid has not been previously identified as a major biliary bile acid in vertebrates. Five of 15 species of the genus Ptilinopus, 5 of 9 species of the genus Ducula, and the only species examined for the genus Gymnophaps contained 23R-hydroxy chenodeoxycholic acid in detectable proportions, ranging from 1 to 4%. Bile acids were conjugated (in N-acyl linkage) with glycine and taurine in 28 species and with only taurine in 2 species. The fruit pigeons are the first non-mammalian genera identified to date in whom bile acids are conjugated with glycine, as well as with taurine. An incidental finding was that a gallbladder was present in 3 genera (Ptilinopus, Ducula, and Gymnophaps) and absent in 4 genera (Gallicolumba, Chalcophaps, Otidiphaps, and Treron).

The diet of cats, Felis catus, on Christmas Island, Indian Ocean

Cats, Felis catus, were taken to Christmas Island (10�25'S,105�40'E) in the Indian Ocean at the time of first settlement in 1888 and a feral population became established soon thereafter. In 1988 a wide range of vertebrate and invertebrate animals was present in the diet of these feral cats, but flying-foxes, Pteropus melanotus, fruit pigeons, Ducula whartoni, and introduced rats, Rattus rattus, together constituted 80% of their food intake by weight. Of the guts examined, 45% contained R. rattus, and this species accounted for 31% of food intake by weight. Less than 10% of cat guts contained P. melanotus and D. whartoni, but the large body weights of these species meant that by weight they made up 21% and 28% respectively. Mus musculus was found in 27% of guts examined, although it contributed only 2% by weight. It is likely that the large numbers of feral cats present in vegetative regrowth on mined areas are related to the ease with which all four primary prey species may be caught there. No evidence was found that cats are having a deleterious effect on native species and they may well be beneficial in stabilising the numbers of R. rattus, which itself can be a serious predator of nesting birds.

1$beta;-Hydroxychenodeoxycholic acid, a new major biliary bile acid in fruit pigeons and pheasants

1$beta;-Hydroxychenodeoxycholic acid, a new major biliary bile acid in fruit pigeons and pheasants

Feeding Ecology of Fruit Pigeons in Subtropical Rainforests of South-Eastern Queensland.

In a 5-yr (1979-84) study of 6 species of fruit pigeon in lowland (dry) and upland (wet) subtropical rain forests in the Jimna and Conondale Ranges, the effects of forest phenology on pigeon abundance were investigated. The pigeons utilized 89 species of plants from 39 families of trees, palms and vines. The seasonal availability of fruit was similar in each forest type: most plant species bore crops during the wet season (Dec.-Mar.) and held crops into the early dry season (April-May); the late dry season (June-Oct.) was a time of general fruit shortage. More than 60% of the species of food plants present in upland forest were rare or absent in lowland forest. In general, each species of pigeon utilized a distinct suite of plant species in each forest type. Certain species of fig (Ficus spp.) fruited asynchronously and were the most important food for sedentary wompoo fruit-doves (Ptilinopus magnificus magnificus) in both forest types. These and other species of fig were the most important food for topknot pigeons (Lopholaimus antarcticus) and rose-crowned fruit-doves (P. regina regina) in lowland forest. An influx of flocks of up to 200 topknot pigeons into upland forest occurred each year in response to the fruiting of Archontophoenix cunninghamiana. The foraging habits of rose-crowned fruit-doves were largely opportunistic in upland forest, utilizing whatever fruit was available at particular times. White-headed pigeons (Columba leucomela) foraged solely in Olea paniculata during irregular visits to lowland forest. A regular summer influx into upland forest occurred in response to the fruiting of a vine, Piper novae-hollandiae. In each forest type, brown cuckoo-doves (Macropygia amboinensis) had a distinct foraging preference for plant species characteristic of disturbed forests; important plant families were the Solanaceae, Ulmaceae, Euphorbiaceae and Araliaceae. Superb fruit-doves (P. superbus) were seldom found in either forest type.

Ein standardisiertes Futter für ernährungsphysiologische Untersuchungen an fruchtfressenden Vögeln

A semi-synthetic diet is described which is successfully used in nutritional studies in different species of fruit pigeons (Treroninae). Agar (1–2%) is used as a hydrophilic colloid to reach the required water amount of 75–80% in the diet.

How Long Fruit-Eating Birds Stay in the Plants Where They Feed: Implications for Seed Dispersal

Theories relating foraging behavior of frugivorous birds to patterns of seed dispersal have not considered the effect of prolonged visits by birds to fruit-bearing plants. We present data showing that in New Guinea some obligate frugivores (fruit pigeons and bowerbirds) spend more time in fruit-bearing plants than is required for feeding. Often they remain in the plant between feeding bouts. On the other hand, some insectivorous fruit-eating birds (birds of paradise) visit fruit-bearing plants only long enough to feed. Longer visits by fruit pigeons and bowerbirds may result, in different cases, from greater commitment to frugivory, to predator and competitor avoidance strategies involving crypsis, and to less time-demanding breeding systems. Longer visits may result in a larger number of seeds being dropped beneath food trees.

Frugivores at a Fruiting Ficus Vine in a Southern Cameroon Tropical Wet Forest

A fruiting Ficus sp. vine in a southern Cameroon tropical wet forest was monitored for 57.75 hours over a 9-day period in early February 1979. Avian frugivores observed eating figs included one fruit pigeon, four hornbill, and three greenbul species. Two species each of monkeys and squirrels also ate figs. Greenbuls were present at 59 percent of the censuses, fruit pigeons at 12 percent, and hornbills at 11 percent. Mean foraging group sizes for greenbuls, fruit pigeons, and hornbills were 1.7, 2.3, and 2.0, respectively. Greenbuls ate an estimated 17,332 fruits over an 8 day period, fruit pigeons 4769, hornbills 2534, and Greater White-nosed Monkeys 811. BIRDS EXPLOITING ABUNDANT, though temporary, singletree fruit crops in the neotropics have been the subject of numerous short-term studies in recent years (see references in Fleming 1979). One such study has been done on New Guinea birds (Terborgh and Diamond 1970), and a longer, broader investigation exists for Malaysia (McClure 1966). More recently, detailed studies have been undertaken on frugivores associated with neotropical trees producing high quality fruit (sensu McKey 1975) (e.g., Howe 1977; Howe and Vande Kerckhove 1979, 1981) and low quality fruit (Howe 1980). Analogous information from the African tropics is conspicuously scarce. Figs (Ficus spp.) are common in tropical, forested regions. Yet, there has been no detailed study of animals visiting even a single fig tree and thus serving as the potential dispersal coterie UJanzen 1979). I report here on rates of exploitation by bird and diurnal mammal frugivores of the large crop of a Ficus vine in a southern Cameroon, tropical, wet forest. STUDY SITE AND METHODS Observations were conducted in primary rain forest bordering Lake Tissongo in the Douala-Edea Faunal Reserve, located about 35 km SW of Edea, Cameroon, and 20 km from the Gulf of Guinea. The Ficus sp. vine was growing at a height of about 20 m in the crown of a slightly emergent leguminous tree. I estimated projection of the vine onto the forest floor as subcircular, 7 m in diameter, and the vertical space occupied in the supporting tree's crown as 3 m. Syconia (fig fruit) were about 1 cm in diameter, spheroidal, and dark red when ripe. Upon my arrival at the site on 28 January 1979, spontaneous dropping of fruit was intermittent. Fruit fall peaked 3-5 February and had declined sharply when observations were terminated on 8 February. Hence, I am confident that I monitored most fruiting of the vine. The fig was monitored for a total of more than 57 hr over a 9-day period, 43 hr of which occurred during the final 4 days. Casual observations were made on bird and mammal visitors from 30 January through 3 February and lengths of foraging bouts by individuals of several species were noted on these days. I conducted 177 censuses on 4-7 February, counting individuals of all species present every 15 min from early morning (about 0630) to late afternoon (about 1730). I noted very few individuals arriving, foraging, and leaving within the 15 min interval between censuses, thus verifying validity of counts made at this interval. Weather data were collected in a nearby forest clearing at the field research station of the Wisconsin Regional Primate Center. Early morning and late afternoon temperatures varied between 22-27?C and midday temperatures between 26-35?C. Two days were cloudless, the remainder hazy to cloudy. There was a trace of rain on 4 days, and 1.5 cm of rain fell on 2 February, all precipitation occurring during daylight hours.

Arils as Food of Tropical American Birds

-In Costa Rica, 16 kinds of trees, lianas, and shrubs produce arillate seeds which are eaten by 95 species of birds. These are listed and compared with the birds that feed on the fruiting spikes of Cecropia trees and berries of the melastome Miconia trinervia. In the Valley of El General, on the Pacific slope of southern Costa Rica, arillate seeds and berries are most abundant early in the rainy season, from March to June or July, when most resident birds are nesting and northbound migrants are leaving or passing through. The oil-rich arils are a valuable resource for nesting birds, especially honeycreepers and certain woodpeckers, and they sustain the migrants. Vireos are especially fond of arils, and Sulphur-bellied Flycatchers were most numerous when certain arillate seeds were most abundant. Many species of birds take arils from the same tree or vine without serious competition. However, at certain trees with slowly opening pods, birds vie for the contents while largely neglecting other foods that are readily available. Although many kinds of fruits eaten by birds may be distinguished morphologically, functionally they fall into two main types, exemplified by the berry and the pod containing arillate seeds. Berries and berrylike fruits are generally indehiscent; no hard or tough integument keeps animals away from the edible tissue. In contrast to a berry, which develops from the ovary, an aril is an outgrowth of the ovule, or of the funicle which attaches it to the placenta. An aril may partly or completely cover the seed. Accordingly, each seed has its own aril, although, when seeds are many and small, their arils may be massed together. Arillate seeds are commonly enclosed in tough or woody pods or capsules, which protect them until mature, at which time the pods split open to expose the seeds prominently. Arils and pods are often of contrasting colors: an aril may be white in a red or yellow pod, or red between yellow valves, the whole conspicuous amid green foliage, easily found by hungry animals, who may disperse the seeds. Rarely, as in granadillas or maypops (Passiflora spp.), arillate seeds are enclosed in a thin, indehiscent pod. Arils of certain passion flowers are also exceptional in being sweetish, although most others that I have tasted have no evident sugar but are often slightly bitter. Many arils are poor in starch but rich in lipids and proteins (McDiarmid et al. 1977). Oils or fats are the chief nonnitrogenous reserves of many seeds, and arils develop from the seeds themselves. Within the soft aril is a seedcoat that is often hard, or somehow able to resist digestion during the short time that the seed remains in the alimentary tract of a small bird. Wallace (1872) described how the Bluetailed Imperial Pigeon (Ducula concinna) swallows the seed of the (Myristica fragrans) and, after digesting the aril or mace, casts up the seed uninjured. Several species of large fruit pigeons (Ducula myristicivora, D. luctuosa, D. bicolor, and D. spilorrhoa) are sometimes known as nutmeg pigeons, and the last two are reported to eat wild nutmegs (Goodwin 1967). The Many-colored Fruit Dove (Ptilinopus perousii) of Samoa and neighboring islands is also known as the nutmeg dove. Pijl (1952) recognized the role of arils in the dispersal of seeds of tropical plants by birds, and gave several examples, including species of New World origin. In a long list of fruits eaten by tanagers and honeycreepers on Trinidad, Snow and Snow (1971) included many species with arillate seeds, belonging to the genera Clusia, Sloanea, Protium, Alchornea, Sapium, Davilla, and Lacistema, but they did not give special attention to arils. I present here my own observations on arils and the birds that eat them, amplifying my earlier account (Skutch 1971). Unless otherwise stated, my observations were made at Los Cusingos, which is situated between Santa Elena and Quizarra in the Valley of El General, on the Pacific slope of southern Costa Rica, at about 750 m above sea level. These records have been gathered over many years, but more intensively during the last four. For comparison, I list the birds that I have seen eat two other at-

The Ecology of Fruit Pigeons in Tropical Northern Queensland.

Seven species of fruit pigeon were studied during 3 years in the lowland tropical forest of N. Queensland to find the effect of forest species on pigeon populations and breeding habits and the basis for coexistence of 7 species. Because of the variety of plant species and the differences in their fruiting seasons, fruit was available all the year round and the diet of each species changed according to the fruit available and the selectivity of their feeding habits; none of the species studied ate anything other than fruits or seeds, the latter representing an appreciable fraction (20%) only in the brown pigeon. The foraging habits of all species were recorded and their relative abundance was assessed. Pigeons were most numerous during the dry season, which was also the breeding season. Each species selected a different range of fruiting plants owing to nomadism and migration. At any one time 2 or 3 pigeon species were common, while the rest were rare or absent. The plant family Lauraceae was of major importance. It is suggested that the many species (2250 in all) in this family have developed collaterally with the fruit-eating birds of appropriate feeding habits.

Sexual Cycles of Pigeons in a Tropical Environment.

The sexual cycles of two genera of frugivorous rain-forest pigeons, Ducula and Ptilinopus, and two ground-feeding pigeons of the open woodland, Geopelia humeralis and G. striata, have been studied at latitude 9D 29'S. in New Guinea. In P, iozonus, P. magnificus, G. humevalis and G. striata some males were sexually active and some females had enlarged follicles in each month of the year and so some individuals, at all times, were capable of breeding; there was an indication that this situation was general in the two genera. In the rain-forest species more birds had enlarged gonads in the late dry season and wet season than at other times. Both sexes of G. stviata had peak gonad size in the late wet and early dry seasons; G. humevalis maintained peak activity throughout the dry season; both species had small gonads in the late dry season. The cycles of gonad size of fruit pigeons and ground-feeding pigeons corresponded to the probable cycle of food abundance in the two habitats. There was no evidence of an effect of photoperiod in Geopelia but it could not be excluded in males of Ptilinopus.

Australian Pigeons: their affinities and status

SummaryThe Australian pigeons are discussed in reference to their affinities within the family Columbidae. All the fruit pigeons, except Lopholaimus are con-specific with or members of the same superspecies as extra-limital forms. The Topknot Pigeon is a unique endemic species. It is considered likely that species related to it formerly existed in Australia. Around Perth the introduced Streptopelia chinensis shows phenotypes with the plumage characters of two different geographical races. It seems probable that Chalcophaps indica and C. stephani cannot co-exist on small islands; the same may be true for indica and “chrysochlora”. The Australian bronzewings are an endemic group which probably derived from some ancestral form not unlike Chalcophaps. The drinking habits of Phaps chalcoptera must have evolved under strong predation by diurnal birds of prey. Geographical variation in Lophophaps and Petrophassa is discussed. Geophaps smithii forms a connecting link between Geophaps seripta and Lophophaps. The Crested Pigeon, Ocyphaps lophotes, is thought to have diverged from some form ancestral to both it and Lophophaps after this ancestral form had become terrestrial. The author is in favour of making Histriophaps a synonym of Phaps, and Geophaps and Lophophaps synonyms of Petrophassa. Geopelia and Leucosarcia are thought to be offshoots of Australian bronzewing stock. The resemblances between Geopelia and Streptopelia are due to convergence. Macropygia is most probably more nearly related to Chalcophaps, leaving aside its obvious allies Reinwardtoena and (possibly) Turacoena.

Taxonomy and Habits of Pigeons

THE taxonomic groupings of the species of pigeons and doves are based primarily on structural characters. Classifications differ in the rank assigned to these characters. In the last fifty years the ranking has fluctuated between extremes. Thus, Salvadori (1893) divides the order Columbae into the suborders Columbae and Didi. W. L. Sclater (1930) reduces these suborders to family rank, Columbidae and Raphidae. Salvadori recognizes five families within his suborder Columbae: Treronidae (fruit pigeons), Columbidae ('true' pigeons), Peristeridae ('ground doves'), Gouridae (crowned pigeons), and Didunculidae (tooth-billed pigeon). Sclater, dealing with African birds only, embraces the first three in his family Columbidae, which carries the implication that he must include therein also Salvadori's Gouridae and Didunculidae. He does not even accord Salvadori's families the rank of subfamilies. Peters's (1937) classification follows Sclater's scheme of two families: Raphidae and Columbidae, but divides the latter into four subfamilies: Treroninae, Columbinae, Gourinae, and Didunculinae. Within the Columbinae, Peters's order of listing is virtually that of Salvadori's families Treronidae, Columbidae, Peristeridae, Gouridae, Didunculidae, and I might add, of Salvadori's subfamilies as well. The taxonomic pendulum alternately swinging from lumping to splitting of genera will perhaps in time prove to be a cultural phenomenon of the same order as the alternations in dress fashions (cf. Richardson and Kroeber, 1940). Best suited for this discussion is the hierarchical grouping set forth by Salvadori. Naturally, I am concerned only with his suborder Columbae, which he divides into five families: Treronidae, Columbidae, Peristeridae, Gouridae, and Didunculidae. I have never kept members of Gouridae nor of Didunculidae. I have had a few Treronidae, but never bred them. The ensuing remarks concern some of the characteristic actions of the living birds and the extent to which these actions coincide with the taxonomic groupings. On the whole there is some degree of correlation between Salvadori's groupings and the actions of the living birds. The following brief notes on characteristic actions of certain pigeons and doves are based on observations of individuals of a number of species, which the writer has kept as aviary inmates at various times over a considerable number of years.