Bill Shape and Size in Honeyeaters and other small Insectivorous Birds in Western Australia

1984 ◽  
Vol 32 (5) ◽  
pp. 657 ◽  
Author(s):  
RD Wooller
Keyword(s):  
Linear Relationship ◽  
Body Mass ◽  
Western Australia ◽  
Clear Relationship ◽  
Cube Root ◽  
Insectivorous Birds ◽  
Flying Insects ◽  
Bill Length ◽  
Shape And Size

Highly nectarivorous honeyeaters, more insectivorous honeyeaters and non-honeyeater insectivores all showed a similar linear relationship between bill length and the cube root of body mass. Bill length increased with body mass at a faster rate in insectivorous honeyeaters than in insectivorous non- honeyeaters. In the more nectarivorous honeyeaters there was no clear relationship between bill length and either bill depth or body mass. It is suggested that mechanical considerations associated with taking large insects from surfaces restrict the length of the bill in both insectivorous non-honeyeaters and, to a lesser extent, in insectivorous honeyeaters. The longer bills of highly specialized honeyeaters may largely restrict them to small flying insects.

Oxygen and the upper limits to animal design and performance.

1998 ◽  
Vol 201 (8) ◽  
pp. 1065-1072 ◽  
Author(s):  
R K Suarez
Keyword(s):  
Energy Metabolism ◽  
Surface Area ◽  
Body Mass ◽  
Current Evidence ◽  
Tracheal System ◽  
Flying Insects ◽  
Upper Limit ◽  
O2 Transport ◽  
Upper Limits ◽  
Functional Capacities

Mass-specific rates of aerobic metabolism VO2/Mb) scale in inverse proportion to body mass (Mb). Thus, small hummingbirds display the highest VO2/Mb known among vertebrates. Among all animals, higher VO2/Mb values are known only in flying insects. The high body-mass-specific rates of metabolism seen in hummingbirds are made possible by high lung O2 diffusing capacities, cardiac outputs, ratios of capillary surface area to muscle fiber surface area, mitochondrial volume densities, cristae surface densities and concentrations of enzymes involved in energy metabolism. Current evidence from control analyses of O2 transport through the respiratory and cardiovascular systems and of metabolic fluxes through pathways of energy metabolism indicates shared control of maximum flux rates among multiple steps (i.e. the absence of single rate-limiting steps). This supports the suggestion that functional capacities at each step in linear pathways or processes are matched to each other, and provides an explanation for why the up-regulation of functional capacities has occurred at virtually all steps in the evolution of the smallest vertebrate homeotherms. Flying insects make use of a tracheal system for O2 transport and, like hummingbirds, possess a highly up-regulated biochemical machinery for substrate oxidation. Studies of hummingbirds and honeybees reveal closer matches between biochemical flux capacities and maximum physiological flux rates than in animals capable of lower maximum VO2/Mb. It is proposed that the upper limits to functional capacities set the upper limit to VO2/Mb. This upper limit to aerobic metabolic rate may contribute, along with other factors, towards establishing the lower limit to vertebrate homeotherm size.

scholarly journals Patterns of Growth in Nestling Indian Barn-Owls

The Condor ◽  
2002 ◽  
Vol 104 (4) ◽  
pp. 885-890 ◽  
Author(s):  
Rajarathinavelu Nagarajan ◽  
Krishinamoorthy Thiyagesan ◽  
Rajagopalan Natarajan ◽  
Ramalingam Kanakasabai
Keyword(s):  
Body Mass ◽  
Body Length ◽  
Wing Length ◽  
Growth Patterns ◽  
The Body ◽  
Logistic Growth ◽  
Adult Size ◽  
Tyto Alba ◽  
Tarsus Length ◽  
Bill Length

Abstract We examined nestling growth patterns of the Indian Barn-Owl (Tyto alba stertens) in Tamilnadu, Southern India, with reference to body mass, body length, bill length, bill width, wing length, wingspan, tail length, tarsus length, and middle claw length. Body mass reached an asymptote of 447.0 ± 6.8 g during week 7, which was 10% higher than the adult mass. Then it significantly declined to 437.0 ± 10.9 g at fledging. At the end of week 4, the body length, bill length, bill width, tarsus length, and middle toe length had surpassed 50% of adult sizes. The wingspan and tarsus length reached almost adult size by the time of fledging. A logistic growth curve was found to be a good fit for all the growth variables and explained between 71% (wing length) and 86% (body length) of the variance. Patrones de Crecimiento en Polluelos de Tyto alba stertens Resumen. Examinamos los patrones de crecimiento de polluelos de Tyto alba stertens en Tamilnadu, sudoeste de India, en relación al peso y el largo del cuerpo, el largo y el ancho del pico, el largo del ala y su envergadura, y el largo de la cola, los tarsos y de la garra mediana. El peso corporal alcanzó una asíntota de 447.0 ± 6.8 g durante la séptima semana, el cual fue un 10% mayor que el peso de los adultos. Posteriormente, durante el período de volantones, el peso corporal disminuyó hasta 437.0 ± 10.9 g. Al final de la cuarta semana, el largo del cuerpo, el largo y el ancho del pico, y los largos del tarso y del dedo mediano habían sobrepasado el 50% de los tamaños adultos. La envergadura del ala y el largo del tarso casi alcanzaron tamaños adultos durante el período de volantones. Se encontró que una curva de crecimiento logístico se ajustó bien a todas las variables de crecimiento y explicó un 71% (largo del ala) y un 86% (largo del cuerpo) de la varianza.

scholarly journals Rainy springs linked to poor nestling growth in a declining avian aerial insectivore ( Tachycineta bicolor )

2019 ◽  
Vol 286 (1898) ◽  
pp. 20190018 ◽  
Author(s):  
Amelia R. Cox ◽  
Raleigh J. Robertson ◽  
Ádám Z. Lendvai ◽  
Kennedy Everitt ◽  
Frances Bonier
Keyword(s):  
Climate Change ◽  
Body Mass ◽  
Food Availability ◽  
Food Resource ◽  
Food Abundance ◽  
Tachycineta Bicolor ◽  
Long Term Study ◽  
Flying Insects ◽  
Food Shortages

As species shift their ranges and phenology to cope with climate change, many are left without a ready supply of their preferred food source during critical life stages. Food shortages are often assumed to be driven by reduced total food abundance, but here we propose that climate change may cause short-term food shortages for foraging specialists without affecting overall food availability. We frame this hypothesis around the special case of birds that forage on flying insects for whom effects mediated by their shared food resource have been proposed to cause avian aerial insectivores' decline worldwide. Flying insects are inactive during cold, wet or windy conditions, effectively reducing food availability to zero even if insect abundance remains otherwise unchanged. Using long-term monitoring data from a declining population of tree swallows ( Tachycineta bicolor ), we show that nestlings’ body mass declined substantially from 1977 to 2017. In 2017, nestlings had lower body mass if it rained during the preceding 3 days, though females increased provisioning rates, potentially in an attempt to compensate. Adult body mass, particularly that of the males, has also declined over the long-term study. Mean rainfall during the nestling period has increased by 9.3 ± 0.3 mm decade −1 , potentially explaining declining nestling body mass and population declines. Therefore, we suggest that reduced food availability, distinct from food abundance, may be an important and previously overlooked consequence of climate change, which could be affecting populations of species that specialize on foraging on flying insects.

Elevated numbers of flying insects and insectivorous birds in riparian buffer strips

2000 ◽  
Vol 78 (5) ◽  
pp. 740-747 ◽  
Author(s):  
Darroch M Whitaker ◽  
Allan L Carroll ◽  
William A Montevecchi
Keyword(s):  
Abies Balsamea ◽  
Agricultural Landscapes ◽  
Riparian Buffer ◽  
Buffer Strips ◽  
Insectivorous Birds ◽  
Size Classes ◽  
Clear Cutting ◽  
Flying Insects ◽  
Riparian Buffer Strips ◽  
Capture Rates

We compared the abundances of flying insects along undisturbed lakeshores and riparian buffer strips in balsam fir (Abies balsamea) forests in western Newfoundland. Insects were collected in pan traps placed on the forest floor and tanglefoot (sticky) traps suspended within the live canopy. Significantly greater numbers of insects were captured in riparian buffer strips than in undisturbed shorelines for four of five size classes in the canopy and two of five size classes in the understory. Collections were dominated by adult Diptera and Hymenoptera. Mean capture rates along buffer strips were 120-200% of the mean capture rates along undisturbed shorelines. This increase was greatest for large-bodied insects. A likely explanation for our observations is that buffer strips act as windbreaks, collecting airborne insects blown in from adjacent clearcuts and lakes. This phenomenon has been widely documented in agricultural landscapes. Understory wind speed was generally greater along buffer strips than controls, which is a reflection of increased exposure caused by clear-cutting. A concurrent parallel study conducted at the same sites investigated the effects of riparian buffering on breeding bird assemblages. Ubiquitous insectivorous birds, including the yellow-rumped warbler (Dendroica coronata) and blackpoll warbler (Dendroica striata), were more abundant along buffer strips than undisturbed shorelines, possibly in response to increased prey availability. Increased food availability may in part explain the high numbers of insectivorous birds typically observed in riparian buffer strips in boreal forests.

scholarly journals Body Mass Index Has a Linear Relationship with Cerebrospinal Fluid Pressure

2012 ◽  
Vol 53 (3) ◽  
pp. 1422 ◽  
Author(s):  
John P. Berdahl ◽  
David Fleischman ◽  
Jana Zaydlarova ◽  
Sandra Stinnett ◽  
R. Rand Allingham ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Cerebrospinal Fluid ◽  
Linear Relationship ◽  
Body Mass ◽  
Fluid Pressure ◽  
Cerebrospinal Fluid Pressure

scholarly journals Variation in pelvic shape and size in Eastern European males: a computed tomography comparative study

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6433 ◽  
Author(s):  
Bartosz Musielak ◽  
Anna Maria Kubicka ◽  
Michał Rychlik ◽  
Jarosław Czubak ◽  
Adam Czwojdziński ◽  
...  
Keyword(s):  
Geometric Morphometrics ◽  
Body Mass ◽  
Three Dimensional ◽  
Opening Angle ◽  
Control Group ◽  
Human Society ◽  
Eastern European ◽  
Adult Males ◽  
Pelvic Shape ◽  
Shape And Size

Background The significantly accelerated development of human society in the last millennium has brought about changes in human behavior and body mass that may have influenced human bone morphology. Our objective was to analyze the variation in pelvic shape and size in males from modern and medieval populations. Methods We obtained 22 pelvic girdles of adult males from a medieval cemetery located in Cedynia, Poland. The control group comprised 31 contemporary male pelves from individuals inhabiting the same region. The analyzed parameters were: interspinous distance (ISD), intercristal distance (ICD), intertuberous distance (ITD), anatomic conjugate of the pelvis, height of the pelvis (HP), iliac opening angle (IOA), iliac tilt angle (ITA), and ISD/ITD/HP ratio. Geometric morphometrics was used to analyze differences in shape in the pelves. All analyses were carried out on three-dimensional CT reconstructions of pelves. Results ISD, ICD, and IOA were significantly greater in modern pelves than in those from Cedynia, but no significant differences were seen between the two groups in ITD, anatomical conjugate, HP, or ITA. ISD/ITD/HP ratios were significantly lower in the Cedynia group. Geometric morphometrics revealed significant differences in pelvic shape between the analyzed groups. Discussion The pelves of modern males are larger, wider, and flatter than those of medieval males. Changes in the set of daily activities that produce mechanical loading and estimated body mass may constitute the main factors explaining pelvic variability. However, differences in ontogenesis should also be taken into consideration, especially since growth in past populations is often found to be reduced relative to modern populations.

Factors affecting nestling condition and timing of egg-laying in the endangered Carnaby’s cockatoo, Calyptorhynchus latirostris

2020 ◽  
Vol 26 (1) ◽  
pp. 22
Author(s):  
Denis A. Saunders ◽  
Rick Dawson ◽  
Peter R. Mawson ◽  
A. O. Nicholls
Keyword(s):  
Body Mass ◽  
Western Australia ◽  
Egg Laying ◽  
Breeding Habitat ◽  
Left Wing ◽  
Factors Affecting ◽  
Failure Data ◽  
Breeding Populations ◽  
Nestling Condition ◽  
Breeding Failure

Carnaby’s cockatoo, Calyptorhynchus latirostris, is endemic to south-western Australia. It has undergone a major decline in range and abundance as a result of extensive removal of breeding and foraging habitat. It is now classified as endangered by the State of Western Australia, the Australian government, and internationally. In order to plan effective conservation management for the species it is important to assess the success of breeding populations throughout its range. In this paper we examine the efficacy of using the relationship between growth in the length of a nestling’s folded left wing and body mass to assess nestling condition, and examine known breeding failure in relation to nestling condition in two breeding populations: one at Coomallo Creek (studied from 1970–2017), and the other at Manmanning (1969–76). Results demonstrated that the lighter the nestlings, the higher the rate of breeding failure. Data from the Coomallo Creek population were used to prepare a table of nestling folded left wing length and body mass as a benchmark for assessing nestling condition in 10 other breeding populations, based on data collected from 1970 to the present. Following extensive clearing that removed foraging and breeding habitat, two of the 10 populations produced nestlings that were significantly lighter than the benchmark, and both populations subsequently declined to extinction. The commencement of egg-laying each season at Coomallo Creek was strongly influenced by total rainfall in the first half of autumn. The length of the egg-laying period between 1970–76 and 2009–17 increased by 5.2 weeks (40%). This increase was related to changes in rainfall and temperature over more than four decades. Despite the lengthening of the egg-laying period, nestling condition was unaffected, suggesting that, at least in the short term, the Carnaby’s cockatoo population at Coomallo Creek is coping with the effects of climate change.

scholarly journals Polygenic basis for adaptive morphological variation in a threatened Aotearoa | New Zealand bird, the hihi ( Notiomystis cincta )

2020 ◽  
Vol 287 (1933) ◽  
pp. 20200948
Author(s):  
Laura Duntsch ◽  
Barbara M. Tomotani ◽  
Pierre de Villemereuil ◽  
Patricia Brekke ◽  
Kate D. Lee ◽  
...  
Keyword(s):  
Body Mass ◽  
Morphological Traits ◽  
Nucleotide Polymorphisms ◽  
Tarsus Length ◽  
Effective Population ◽  
Chromosome Partitioning ◽  
Genome Wide ◽  
Small Effect Size ◽  
Bill Length ◽  
Notiomystis Cincta

To predict if a threatened species can adapt to changing selective pressures, it is crucial to understand the genetic basis of adaptive traits, especially in species historically affected by severe bottlenecks. We estimated the heritability of three hihi ( Notiomystis cincta ) morphological traits known to be under selection (nestling tarsus length, body mass and head–bill length) using 523 individuals and 39 699 single nucleotide polymorphisms (SNPs) from a 50 K Affymetrix SNP chip. We then examined the genetic architecture of the traits via chromosome partitioning analyses and genome-wide association scans (GWAS). Heritabilities estimated using pedigree relatedness or genomic relatedness were low. For tarsus length, the proportion of genetic variance explained by each chromosome was positively correlated with its size, and more than one chromosome explained significant variation for body mass and head–bill length. Finally, GWAS analyses suggested many loci of small effect contributing to trait variation for all three traits, although one locus (an SNP within an intron of the transcription factor HEY2 ) was tentatively associated with tarsus length. Our findings suggest a polygenic nature for the morphological traits, with many small effect size loci contributing to the majority of the variation, similar to results from many other wild populations. However, the small effective population size, polygenic architecture and already low heritabilities suggest that both the total response and rate of response to selection are likely to be limited in hihi.

scholarly journals Intraspecific variation in wing loading affects habitat use by little brown bats (Myotis lucifugus)

1995 ◽  
Vol 73 (1) ◽  
pp. 89-95 ◽  
Author(s):  
Matina C. Kalcounis ◽  
R. Mark Brigham
Keyword(s):  
Habitat Use ◽  
Body Mass ◽  
Selective Advantage ◽  
Myotis Lucifugus ◽  
Wing Loading ◽  
Interspecific Differences ◽  
Insect Trap ◽  
Flying Insects ◽  
The Relationship ◽  
Little Brown Bats

Morphological constraints have been linked to habitat partitioning by different species of animals. Interspecific differences have been explored, but less is known about the relationship between individuals of the same species. The purpose of this study was to determine if habitat use by little brown bats (Myotis lucifugus) varies with body mass of individuals. From aerodynamic theory, we predicted that bats with higher body mass will have higher wing loadings, should be less manoeuvrable, and thus tend to forage in areas where there are fewer obstacles to detect and avoid (clutter). Habitat was ranked into four zones based on the degree of clutter, and habitat use was assessed by measuring the time that males and non-reproductive, pregnant, lactating, postlactating, and artificially loaded females spent in each habitat zone. To test the assumption that a selective advantage accrues to bats foraging in clutter, we measured the availability of flying insects in cluttered and open habitats. Insect trap samples revealed a higher density of insect prey in more cluttered habitats. Body mass was positively correlated with wing loading. Overall, males were smaller than females with respect to mass and wing loading; however, these differences did not translate into differential habitat use. As predicted, there was a significant relationship between individual wing loading and habitat use, with heavier bats (greater wing loading) foraging in less cluttered areas.

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