The role of competition in determining morphological differences between Victorian and Tasmanian passerine birds

Bill length, tarsus length and wing length were measured in 107 passerine species in southern Victoria and 46 in Tasmania, and the possibility that the impoverishment of the Tasmanian avifauna elicits morphological shifts was evaluated. An hypothesis of competitor release failed to account for the main morphological features of the Tasmanian avifauna. There was no significant difference between the frequency distributions of the three variables in mainland and island species, which suggests that no character size on the mainland is over- or under-represented in Tasmania; in spite of this, in nearly all the species common to both areas all three variables are significantly larger in Tasmania. No significant difference was found between the frequency distributions of character-ratios for mainland and island congeneric species-pairs, though theory predicts the island distribution would be the more skew. In 17 pairs of congeners occurring in both areas, the bill length and tarsus length ratios are not significantly different, and though wing length ratios do differ significantly, it is the mainland pairs that have the larger ratio. The variability of the three characters in 25 species did not differ significantly between mainland and island. Many genera which are represented by several sympatric species in Victoria have only one representative (usually the larger) in Tasmania. Although the theory of competitor release predicts that the species in Tasmania should show decreased character sizes, a clear-cut trend to increased size was found. Congeneric species-pairs in Tasmania do not show large morphological differences, which cannot be necessary for successful coexistence there. The above results are discussed briefly, and an hypothesis based on the larger size of food items in Tasmania is proposed to explain them.

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Patterns of Growth in Nestling Indian Barn-Owls

The Condor ◽

10.1093/condor/104.4.885 ◽

2002 ◽

Vol 104 (4) ◽

pp. 885-890 ◽

Cited By ~ 1

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.

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Bergmann’s rule and Allen’s rule in two passerine birds in China

Avian Research ◽

10.1186/s40657-019-0172-7 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 5

Author(s):

Liqing Fan ◽

Tianlong Cai ◽

Ying Xiong ◽

Gang Song ◽

Fumin Lei

Keyword(s):

Body Size ◽

Wing Length ◽

Chinese Mainland ◽

Bergmann’S Rule ◽

Passerine Birds ◽

Bergmann's Rule ◽

Tarsus Length ◽

Heat Conservation ◽

Allen’S Rule ◽

Bill Length

Abstract Background Animals that live at higher latitudes/elevations would have a larger body size (Bergmann’s rule) and a smaller appendage size (Allen’s rule) for thermoregulatory reasons. According to the heat conservation hypothesis, large body size and small appendage size help animals retain heat in the cold, while small body size and large appendage size help them dissipate heat in the warm. For animals living in seasonal climates, the need for conserving heat in the winter may tradeoff with the need for dissipating heat in the summer. In this study, we tested Bergmann’s rule and Allen’s rule in two widely-distributed passerine birds, the Oriental Magpie (Pica serica) and the Oriental Tit (Parus minor), across geographic and climatic gradients in China. Methods We measured body size (body mass and wing length) and appendage size (bill length and tarsus length) of 165 Oriental Magpie and 410 Oriental Tit individuals collected from Chinese mainland. We used linear mixed-effect models to assess variation patterns of body size and appendage size along geographic and climatic gradients. Results Oriental Magpies have a larger appendage size and Oriental Tits have a smaller body size in warmer environments. Appendage size in Oriental Magpies and body size in Oriental Tits of both sexes were more closely related to the climates in winter than in summer. Minimum temperature of coldest month is the most important factor related to bill length and tarsus length of male Oriental Magpies, and wing length of male and female Oriental Tits. Bill length and tarsus length in female Oriental Magpies were related to the annual mean temperature and mean temperature of coldest quarter, respectively. Conclusions In this study, Oriental Magpies and Oriental Tits followed Allen’s rule and Bergmann’ rule respectively. Temperatures in the winter, rather than temperatures in the summer, drove morphological measurements in Oriental Magpies and Oriental Tits in Chinese mainland, demonstrating that the morphological measurements reflect selection for heat conservation rather than for heat dissipation.

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Lack of genetic differentiation between two sympatric species of Astyanax (Characidae:Teleostei) in Lake Catemaco, Mexico

10.21203/rs.2.22839/v1 ◽

2020 ◽

Author(s):

Ignacio Doadrio ◽

Patricia Ornelas ◽

Elena G. Gonzalez ◽

Diethard Tautz

Keyword(s):

Genetic Differentiation ◽

Genetic Basis ◽

Single Gene ◽

Ecological Speciation ◽

Sympatric Species ◽

Morphological Divergence ◽

Wide Range ◽

Species Pairs ◽

Morphological Differences ◽

Trophic Niches

Abstract Background Fish of the genus Astyanax are known to be able to adapt to a wide range of ecological conditions and are especially known for repeated colorizations of cave systems. In lakes they often occur in species pairs. In the case we study here, they show major morphological differences, such that they were originally classified in different genera. Previous studies have shown that these morphological differences correlate with occupation of different trophic niches. Hence, this could be an example of ecological speciation under sympatric conditions, which predicts that differential ecological adaptation becomes coupled to assortative mating and to the formation of genetically distinct groups that may be called species. We have tested this prediction by typing a set of microsatellites for the two morphs in the lake in comparison to an allopatric population.Results While we find the expected differentiation with respect to the allopatric population, there is a complete lack of genetic differentiation between the two morphs within the lake. Hence, the two morphs in the lake are either in an extremely early phase of speciation or represent two extreme morphotypes derived from a single gene pool.Conclusions Even when we failed to recover the two morphs as reproductively isolated, this model provides a unique opportunity to characterize those factors that would promote the ecological divergence, thus, our lacustrine morphs system gives a unique opportunity to understand the genetic basis of how morphological divergence in the presence of gene flow.

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Quantitative Trait Loci Affecting Differences in Floral Morphology Between Two Species of Monkeyflower (Mimulus)

Genetics ◽

10.1093/genetics/149.1.367 ◽

1998 ◽

Vol 149 (1) ◽

pp. 367-382 ◽

Cited By ~ 11

Author(s):

H D Bradshaw ◽

Kevin G Otto ◽

Barbara E Frewen ◽

John K McKay ◽

Douglas W Schemske

Keyword(s):

Quantitative Trait Loci ◽

Reproductive Isolation ◽

Quantitative Trait ◽

Floral Morphology ◽

Cumulative Effect ◽

Sympatric Species ◽

Accurate Estimate ◽

Phenotypic Variance ◽

Trait Loci ◽

Morphological Differences

Abstract Conspicuous differences in floral morphology are partly responsible for reproductive isolation between two sympatric species of monkeyflower because of their effect on visitation of the flowers by different pollinators. Mimulus lewisii flowers are visited primarily by bumblebees, whereas M. cardinalis flowers are visited mostly by hummingbirds. The genetic control of 12 morphological differences between the flowers of M. lewisii and M. cardinalis was explored in a large linkage mapping population of F2 plants (n = 465) to provide an accurate estimate of the number and magnitude of effect of quantitative trait loci (QTLs) governing each character. Between one and six QTLs were identified for each trait. Most (9/12) traits appear to be controlled in part by at least one major QTL explaining ≥25% of the total phenotypic variance. This implies that either single genes of individually large effect or linked clusters of genes with a large cumulative effect can play a role in the evolution of reproductive isolation and speciation.

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Comparative morphology of two sympatric Pareledone species from South Georgia

Antarctic Science ◽

10.1017/s0954102094000258 ◽

1994 ◽

Vol 6 (2) ◽

pp. 163-169 ◽

Cited By ~ 8

Author(s):

Heather I. Daly ◽

Paul G. Rodhouse

Keyword(s):

Reproductive Isolation ◽

Body Mass ◽

Comparative Morphology ◽

Sympatric Species ◽

Morphometric Data ◽

South Georgia ◽

Buccal Mass ◽

Significant Difference ◽

Sharp Point ◽

Trophic Niches

Morphometric data were collected for 410 specimens of Pareledone turqueti and P. polymorpha caught around South Georgia. The two species differ in beak morphology and in the male hectocotylus. The species have similar appearances although there is a small but significant difference in the mantle length/body mass relationship for females, with P. polymorpha having a relatively longer mantle. There is no significant difference in the arm length/body mass relationship between species or sexes (p>0.05), except in the case of arm IV of females. There is an interspecific significant difference between sucker number on arms I and II of males, arms I–IV of females, and between hood length and mass of the buccal mass (p<0.05), with P. turqueti having relatively lower sucker numbers, a longer hood length and greater buccal mass mass. The beak of P. turqueti is similar to that of Eledone spp. but P. polymorpha has a small, fine beak with the rostral tip ending in an elongated, sharp point. Differences in beak and buccal mass suggest that these sympatric species occupy distinct trophic niches and that the differing morphology of the male hectocotylus is a factor in reproductive isolation.

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Temporal distribution and population structure of two congeneric species ofCucullanus(Nematoda: Cucullanidae) inOrthopristis ruberin Venezuela

Journal of Helminthology ◽

10.1017/s0022149x08873567 ◽

2008 ◽

Vol 82 (1) ◽

pp. 69-76 ◽

Cited By ~ 1

Author(s):

A.K. Bashirullah ◽

M.T. Diaz

Keyword(s):

Temporal Distribution ◽

Caribbean Sea ◽

Congeneric Species ◽

Mean Intensity ◽

Qualitative And Quantitative ◽

The North ◽

Significant Difference ◽

The Caribbean ◽

Over Exploitation ◽

Fish Hosts

AbstractThe qualitative and quantitative parameters of temporal distribution ofCucullanus tripapillatusandCucullanus chrysophrydesin the intestine ofOrthopristis ruberin the Caribbean Sea on the north of Margarita Island, Venezuela were analysed. A total of 540 fish were collected at random from the catch of commercial trawlers during 1982–83 and 1992–93. Both species ofCucullanuswere found throughout the year; prevalence and mean intensity ofC. tripapillatuswere higher than that ofC. chrysophrydes. A significant difference was found in infection between the two years of sampling. Female worms were more abundant than male in both years. Both species exhibited pronounced prevalence and maturity in September and March of each year, indicating seasonality. The patterns of occurrence of the two species ofCucullanusinO. ruberdid not change in the 10-year interval but the host size and number of parasites declined, which may be due to over-exploitation of definitive fish hosts.

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Sympatry drives colour and song evolution in wood-warblers (Parulidae)

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.2804 ◽

2021 ◽

Vol 288 (1942) ◽

pp. 20202804

Author(s):

Richard K. Simpson ◽

David R. Wilson ◽

Allison F. Mistakidis ◽

Daniel J. Mennill ◽

Stéphanie M. Doucet

Keyword(s):

Related Species ◽

Species Recognition ◽

Sympatric Species ◽

Signal Evolution ◽

Wood Warblers ◽

Mixed Support ◽

Species Pairs ◽

Song Divergence ◽

Signal Diversity ◽

Signal Divergence

Closely related species often exhibit similarities in appearance and behaviour, yet when related species exist in sympatry, signals may diverge to enhance species recognition. Prior comparative studies provided mixed support for this hypothesis, but the relationship between sympatry and signal divergence is likely nonlinear. Constraints on signal diversity may limit signal divergence, especially when large numbers of species are sympatric. We tested the effect of sympatric overlap on plumage colour and song divergence in wood-warblers (Parulidae), a speciose group with diverse visual and vocal signals. We also tested how number of sympatric species influences signal divergence. Allopatric species pairs had overall greater plumage and song divergence compared to sympatric species pairs. However, among sympatric species pairs, plumage divergence positively related to the degree of sympatric overlap in males and females, while male song bandwidth and syllable rate divergence negatively related to sympatric overlap. In addition, as the number of species in sympatry increased, average signal divergence among sympatric species decreased, which is likely due to constraints on warbler perceptual space and signal diversity. Our findings reveal that sympatry influences signal evolution in warblers, though not always as predicted, and that number of sympatric species can limit sympatry's influence on signal evolution.

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Genome assembly, structural variants, and genetic differentiation between Lake Whitefish young species pairs (Coregonus sp.) with long and short reads

10.1101/2022.01.15.476463 ◽

2022 ◽

Author(s):

Claire M&eacuterot ◽

Kristina S R Stenl&oslashkk ◽

Clare Venney ◽

Martin Laporte ◽

Michel Moser ◽

...

Keyword(s):

Transposable Elements ◽

Genetic Architecture ◽

Large Fraction ◽

Sympatric Species ◽

Secondary Contact ◽

Species Differentiation ◽

Lake Whitefish ◽

Structural Variants ◽

Species Pairs ◽

Long Read

The parallel evolution of nascent pairs of ecologically differentiated species offers an opportunity to get a better glimpse at the genetic architecture of speciation. Of particular interest is our recent ability to consider a wider range of genomic variants, not only single-nucleotide polymorphisms (SNPs), thanks to long-read sequencing technology. We can now identify structural variants (SVs) like insertions, deletions, and other structural rearrangements, allowing further insights into the genetic architecture of speciation and how different variants are involved in species differentiation. Here, we investigated genomic patterns of differentiation between sympatric species pairs (Dwarf and Normal) belonging to the Lake Whitefish (Coregonus clupeaformis) species complex. We assembled the first reference genomes for both Dwarf and Normal Lake Whitefish, annotated the transposable elements, and analysed the genome in the light of related coregonid species. Next, we used a combination of long-read and short-read sequencing to characterize SVs and genotype them at population-scale using genome-graph approaches, showing that SVs cover five times more of the genome than SNPs. We then integrated both SNPs and SVs to investigate the genetic architecture of species differentiation in two different lakes and highlighted an excess of shared outliers of differentiation. In particular, a large fraction of SVs differentiating the two species was driven by transposable elements (TEs), suggesting that TE accumulation during a period of allopatry predating secondary contact may have been a key process in the speciation of the Dwarf and Normal Whitefish. Altogether, our results suggest that SVs play an important role in speciation and that by combining second and third generation sequencing we now have the ability to integrate SVs into speciation genomics.

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Peningkatan Status Perkembangan Anak Prasekolah dengan Stimulasi Perkembangan

JKEP ◽

10.32668/jkep.v5i2.363 ◽

2020 ◽

Vol 5 (2) ◽

pp. 150-160

Author(s):

Santun Setiawati ◽

Agus Citra Dermawan ◽

Raden Siti Maryam

Keyword(s):

Univariate Analysis ◽

Wilcoxon Test ◽

Good Growth ◽

Frequency Distributions ◽

Growth Status ◽

Development Status ◽

Significant Difference ◽

Before And After ◽

Quasi Experimental ◽

Children Development

The children are not small adults, but have unique characteristics that are always growing and evolving since their conception until the end of adolescence. Good growth and development of children requires appropriate stimulation and accordance with the age such as developmental stimulation. The aim of this study was to determine the influence development simulations towards pre-school children’s growth status. This research was using the quasi-experimental design without control. The numbers of respondents were 30 children (with aged 60-72 month). The children with dubious developmental status had performed the development stimulations for 2 weeks for 3-4 housr a day and evaluated the development status. Developmental Pre-Screening Questionnaire (KPSP) instrument used in this research. The data analysis was using univariate analysis (frequency distributions), bivariate (Wilcoxon test) and multivariate (ANCOVA test). There was a significant difference in the children’s development status before and after development stimulation interventions (p= 0.000), but there was no children and mothers’ characteristic factors that affect the children development status. Stimulation associated with the value of child development, where the high category of stimulation is not found in children whose development category is slow. So it takes stimulation of children from an early age. Growth stimulations can be done routinely as a part of efforts to improve the children development status.

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A Retrospective Study of Ultrasound Characteristics and Macroscopic Findings in Confirmed Malignant Pleural Effusion

Pulmonary Medicine ◽

10.1155/2019/5628267 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6

Author(s):

Nevenka Piskac Zivkovic ◽

Igor Cikara ◽

Nina Petra Novak ◽

Boris Brkljacic ◽

Neven Tudoric

Keyword(s):

Pleural Effusion ◽

Malignant Pleural Effusion ◽

Diagnostic Significance ◽

Macroscopic Appearance ◽

Frequency Distributions ◽

Thoracic Ultrasound ◽

Pleural Thickening ◽

Diagnostic Potential ◽

Number Of Patients ◽

Significant Difference

Background. A definitive diagnosis of malignant pleural effusion (MPE) is reached by cytological or histological assessment, but thorough analysis of the ultrasound features of the effusion as well as pleural thickening or nodularity can also be of significant diagnostic help. Objective. To assess the relationship of specific ultrasound characterisctics and macroscopic features of confirmed malignant pleural effusion, thus increasing the diagnostic potential of thoracic ultrasound. Methods. The findings of thoracic ultrasonography performed prior to initial thoracentesis in 104 patients with subsequently confirmed malignant pleural effusion were analyzed with regard to the macroscopic features of the pleural effusion. Results. Distribution in terms of frequency of hemorrhagic/sanguinolent (n=64) in relation to nonhemorrhagic transparent/opaque (n=40) MPE, regardless of their ultrasound characteristics, did not yield a statistically significant correlation (p=0.159). Conversely, the frequency distribution of hemorrhagic pleural effusions (n=8) in relation to nonhemorrhagic effusions (n=1), in the group of septated MPE, showed a statistically significant difference (p<0.001). The least number of patients (0.96%) had a complex septated MPE combined with the macroscopic appearance of a serous/transparent nonhemorrhagic effusion, which suggests that this combination is a sporadic occurrence and may have a diagnostic significance for this patient group. Conclusion. The incidence of specific combinations of the ultrasound characteristics and macroscopic appearance of MPEs showed different frequency distributions, which may improve the diagnostic value of thoracic ultrasound in this patient population.

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