scholarly journals New Zealand's extinct giant raptor ( Hieraaetus moorei ) killed like an eagle, ate like a condor

2021 ◽  
Vol 288 (1964) ◽  
Author(s):  
A. H. van Heteren ◽  
S. Wroe ◽  
L. R. Tsang ◽  
D. R. Mitchell ◽  
P. Ross ◽  
...  
Keyword(s):  
Prey Capture ◽  
Mechanical Performance ◽  
Rapid Evolution ◽  
Geometric Morphometric ◽  
Feeding Methods ◽  
Predatory Birds ◽  
Andean Condor ◽  
Vultur Gryphus ◽  
The Relationship ◽  
Biomechanical Strength

The extinct Haast's eagle or harpagornis ( Hieraaetus moorei ) is the largest known eagle. Historically, it was first considered a predator, then a scavenger, but most recent authors have favoured an active hunting ecology. However, the veracity of proposed similarities to carrion feeders has not been thoroughly tested. To infer feeding capability and behaviour in harpagornis, we used geometric morphometric and finite-element analyses to assess the shape and biomechanical strength of its neurocranium, beak and talons in comparison to five extant scavenging and predatory birds. The neurocranium of harpagornis is vulture-like in shape whereas its beak is eagle-like. The mechanical performance of harpagornis is closer to extant eagles under biting loads but is closest to the Andean condor ( Vultur gryphus ) under extrinsic loads simulating prey capture and killing. The talons, however, are eagle-like and even for a bird of its size, able to withstand extremely high loads. Results are consistent with the proposition that, unlike living eagles, harpagornis habitually killed prey larger than itself, then applied feeding methods typical of vultures to feed on the large carcasses. Decoupling of the relationship between neurocranium and beak shape may have been linked to rapid evolution.

scholarly journals Analysis of skull morphometric characters in diurnal raptors (Accipitriformes and Falconiformes)

2019 ◽  
Vol 27 (1) ◽  
pp. 117-131 ◽  
Author(s):  
Tibor Pecsics ◽  
Miklós Laczi ◽  
Gergely Nagy ◽  
Tamás Kondor ◽  
Tibor Csörgő
Keyword(s):  
Relative Size ◽  
Principal Component ◽  
Prey Preference ◽  
Skull Morphology ◽  
Geometric Morphometric ◽  
Morphometric Characters ◽  
Lacrimal Bone ◽  
Physical Attributes ◽  
Predatory Birds ◽  
The Relationship

Abstract Diurnal birds of prey (Accipitriformes and Falconiformes) has traditionally been known as comprising a single order. Recently, this classification has been used in the non-taxonomic sense as referring to a convergent group of birds that are largely classified as predatory birds. Although these birds are similar in their morphology, the species differ in their foraging methods and prey preference. The cranial shape and the physical attributes determine the efficiency of the resource use. The aim of this study is to increase our knowledge of the relationship between skull shape, prey preference, and foraging habits. A geometric morphometric approach was used to analyse two-dimensional cranial landmarks. We used principal component (PC) analyses on measurements that may be related to prey preference and foraging habits. The PCs are resulted described the relative height of the skull and beak, the variation in the relative size, the orientation and robustness of the lacrimal bone, the variation in the relative size of the neurocranium compared to the viscerocranium, and the orientation of the palatine bone. The dietary categories significantly overlap. The skull morphology reflects more on foraging habits than diet or prey preference.

TO STUDY THE DYNAMICS OF IMMUNITY IN BLACK-AND-WHITE COWS DEPENDING ON AGE

2020 ◽  
pp. 49-52
Author(s):  
М.В. ДОВЫДЕНКОВА
Keyword(s):  
Bactericidal Activity ◽  
Phagocytic Activity ◽  
Physiological State ◽  
Age Groups ◽  
Statistical Processing ◽  
Natural Resistance ◽  
Black And White ◽  
Feeding Methods ◽  
High Degree ◽  
The Relationship

Проведена статистическая обработка сформированной базы данных показателей неспецифической резистентности MS «Excel» с целью изучения динамики иммунитета по параметрам бактерицидной, лизоцимной и фагоцитарной активности у крупного рогатого скота черно-пестрой породы разных возрастов. Было установлено, что средние значения показателей лизоцимной и бактерицидной активности у телят в 6 мес были ниже (47,89% и 49,09%, соответственно), чем у животных в 3—4 года (53,75% и 52,81%). Выведено уравнение регрессии, описывающее взаимосвязь между средними показателями фагоцитарной активности и возрастом при высокой степени достоверности (R2=0,90). Изменения лизоцимной и бактерицидной активности в зависимости от возраста были недостоверными (R2=0,58 и R2=0,49, соответственно). Установлена высокая корреляция между бактерицидной и лизоцимной активностью. Отмечена динамика изменения неспецифического иммунитета у коров различных возрастных групп. Создание баз данных и постоянный мониторинг основных показателей естественной резистентности в зависимости от различных факторов (породы, возраста, стадий лактации, кормления, способов содержания), которые влияют на данные показатели, необходимо для оценки физиологического состояния организма животных и их устойчивости к болезням. Statistical processing of the generated MS "Excel" on indicators of non-specific resistance database was carried out with the aim of studying the dynamics of the development of immunity in terms of bactericidal, lysozyme and phagocytic activity in black-and-white cattle of different ages. It was found that the average values of indicators of lysozyme and bactericidal activity in calves at 6 months were lower (47.89% and 49.09%, respectively) than in animals at the age of 3—4 years (53.75% and 52.81%). The equation of regression was derived, it describes the relationship between the average indicators of phagocytic activity and the age with a high degree of reliability (R2=0.90). The changes in lysozyme and bactericidal activity depending on age were dubious (R2=0.58 and R2=0.49, respectively). The high correlation between bactericidal and lysozyme activity was established. It was noticed that the cows of different age groups experienced the dynamics of changes in nonspecific immunity. The creation of databases and constant monitoring of the main indicators of natural resistance, depending on various factors (breed, age, stages of lactation, feeding, methods of keeping) that affect these indicators, is necessary for assessing the physiological state of the animals’ body of and their resistance to diseases.

scholarly journals Review of the relationship between aggregates geology and Los Angeles and micro-Deval tests

2021 ◽  
Vol 80 (3) ◽  
pp. 1963-1980
Author(s):  
Solomon Adomako ◽  
Christian John Engelsen ◽  
Rein Terje Thorstensen ◽  
Diego Maria Barbieri
Keyword(s):  
Los Angeles ◽  
Crystal Size ◽  
Grain Shape ◽  
Mechanical Performance ◽  
Pore Space ◽  
Construction Material ◽  
Engineering Properties ◽  
Coarse Grained ◽  
The Impact ◽  
The Relationship

AbstractRock aggregates constitute the enormous volume of inert construction material used around the globe. The petrologic description as igneous, sedimentary, and metamorphic types establishes the intrinsic formation pattern of the parent rock. The engineering properties of these rocks vary due to the differences in the transformation process (e.g. hydrothermal deposits) and weathering effect. The two most common mechanical tests used to investigate the performance of aggregates are the Los Angeles (LA) and micro-Deval (MD) tests. This study reviewed the geological parameters (including mineralogy, grain and crystal size, grain shape, and porosity) and the relationship to Los Angeles and micro-Deval tests. It was found that high content of primary minerals in rocks (e.g. quartz and feldspar) is a significant parameter for performance evaluation. Traces of secondary and accessory minerals also affect the performance of rocks, although in many cases it is based on the percentage. Furthermore, some studies showed that the effect of mineralogic composition on mechanical strength is not sufficient to draw final conclusions of mechanical performance; therefore, the impact of other textural characteristics should be considered. The disposition of grain size and crystal size (e.g. as result of lithification) showed that rocks composed of fine-grain textural composition of ≤ 1 mm enhanced fragmentation and wear resistance than medium and coarse grained (≥ 1 mm). The effect of grain shape was based on convex and concave shapes and flat and elongated apexes of tested samples. The equidimensional form descriptor of rocks somehow improved resistance to impact from LA than highly flat and elongated particles. Lastly, the distribution of pore space investigated by means of the saturation method mostly showed moderate (R = 0.50) to strong (R = 0.90) and positive correlations to LA and MD tests.

scholarly journals Modelling the elastic mechanical properties of bioactive glass-derived scaffolds

2020 ◽  
Vol 6 (1) ◽  
pp. 50-56
Author(s):  
Francesco Baino ◽  
Elisa Fiume
Keyword(s):  
Elastic Properties ◽  
Poisson’S Ratio ◽  
Mechanical Performance ◽  
Solid Material ◽  
Poisson's Ratio ◽  
Predictive Capability ◽  
Shear Moduli ◽  
Wide Range ◽  
Constitutive Parameters ◽  
The Relationship

AbstractPorosity is known to play a pivotal role in dictating the functional properties of biomedical scaffolds, with special reference to mechanical performance. While compressive strength is relatively easy to be experimentally assessed even for brittle ceramic and glass foams, elastic properties are much more difficult to be reliably estimated. Therefore, describing and, hence, predicting the relationship between porosity and elastic properties based only on the constitutive parameters of the solid material is still a challenge. In this work, we quantitatively compare the predictive capability of a set of different models in describing, over a wide range of porosity, the elastic modulus (7 models), shear modulus (3 models) and Poisson’s ratio (7 models) of bioactive silicate glass-derived scaffolds produced by foam replication. For these types of biomedical materials, the porosity dependence of elastic and shear moduli follows a second-order power-law approximation, whereas the relationship between porosity and Poisson’s ratio is well fitted by a linear equation.

The relationship between forelimb morphology and behaviour in North American carnivores (Carnivora)

1999 ◽  
Vol 77 (7) ◽  
pp. 1064-1074 ◽  
Author(s):  
Andrew N Iwaniuk ◽  
Sergio M Pellis ◽  
Ian Q Whishaw
Keyword(s):  
North American ◽  
Significant Relationship ◽  
Feeding Behaviour ◽  
Prey Capture ◽  
Relative Size ◽  
Independent Contrasts ◽  
Important Indicator ◽  
Predatory Behaviour ◽  
Olecranon Process ◽  
The Relationship

We tested the validity of previously described relationships between forelimb structure and behaviour in mammals by measuring the forelimbs of 22 species of North American carnivores. Nine ratios were calculated from these measurements and made independent of the effects of allometry and phylogeny through the use of log-transformed regressions and independent contrasts analysis. The ratios were then directly compared with two behavioural traits: arboreal locomotion and vertebrate predation. Only five of the nine ratios exhibited a significant relationship with arboreal locomotion and three with vertebrate predation. It was concluded that the brachial index, relative size of the olecranon process, and total forelimb robusticity may be reliable predictors of arboreal locomotion, and that the brachial index, relative size of the olecranon process, and radial robusticity may be accurate predictors of vertebrate predation. The data also suggest that the morphology of the lower forelimb may be an important indicator of prey-capture and feeding behaviour in carnivores and could be used in conjunction with craniodental variables to extrapolate predatory behaviour of extinct species.

scholarly journals Ectoparasitism of the feather chewing louse Colpocephalum trichosum on the Andean Condor Vultur gryphus

2021 ◽  
Vol 7 (1) ◽  
pp. 459-464
Author(s):  
Pablo Sebastián Padrón ◽  
Anahi Hidalgo ◽  
Nicole Ormaza ◽  
Sebastián Kohn ◽  
Fabricio Narvaez ◽  
...  
Keyword(s):  
Chewing Louse ◽  
Andean Condor ◽  
Vultur Gryphus

Some notes on the relationship of plant viruses with vector and non-vector insects

Parasitology ◽  
1941 ◽  
Vol 33 (1) ◽  
pp. 110-116 ◽  
Author(s):  
Kenneth M. Smith
Keyword(s):  
Sugar Beet ◽  
Experimental Evidence ◽  
Plant Viruses ◽  
Artificial Feeding ◽  
The Body ◽  
The Other ◽  
Insect Vector ◽  
Feeding Methods ◽  
Relationship Of ◽  
The Relationship

Extracts of caterpillars and other insects are shown to inhibit the infective power of tobacco mosaic and tobacco necrosis viruses. The inhibitor is not sedimented after spinning for 2½ hr. at 30,000 r.p.m. Experiments with non-vector insects such as caterpillars have shown that the virus of sugar-beet curly-top, of tobacco ringspot and other viruses, are destroyed within the body of the insect. On the other hand, tobacco mosaic virus passes through the body of the caterpillar unchanged though greatly reduced in concentration. By the use of the specific insect vector and artificial feeding methods it was possible to recover the virus of curly-top 24 hr. after it had been injected into the blood of the caterpillar but the viruses of tobacco mosaic and tobacco necrosis could not be so recovered. Experimental evidence is given to show that the virus of beet curly-top is present in the saliva of viruliferous insects.

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