scholarly journals Orientation cues and mechanisms used during avian navigation: A review

2021 ◽  
Vol 13 (2) ◽  
pp. 627-640
Author(s):  
Tushar Tyagi ◽  
Sanjay Kumar Bhardwaj
Keyword(s):  
Migratory Birds ◽  
Field Studies ◽  
Magnetic Compass ◽  
Spatial Cues ◽  
Sun Compass ◽  
Long Time ◽  
Celestial Rotation ◽  
Compass Mechanisms ◽  
And Migration ◽  
Navigational Systems

The navigational systems of different animal species are by a wide margin less notable as compared to birds. Humans have been interested in how migratory birds discover their way more than thousands of miles for quite a long time. This review summarizes the cues and compass mechanisms applied in orientation and navigation by non-migrants, diurnal and nocturnal migrants. The magnetic compass, landmarks, olfactory, and memory of spatial cues en route were utilized in homing and migration. The equivalent is valid for the sun compass despite the fact that its job during migration might be undeniably less significant than commonly presumed. Stellar compass and celestial rotation, as a result of their nighttime accessibility, appear to influence the direction of nighttime migrants during the course of migration. The celestial cues go through notable changes because of the latitude shift during bird migration. Sunset cues alter their location with seasons and latitudes. The recognizable stars lose height and lastly vanish underneath the horizon, whereas new stars show up. These new ones must be calibrated. As celestial rotation not imparting a reference, it is not unexpected that the magnetic compass turns into the main cue that controls the directional importance of stars and sunset cues. Field studies have revealed that, in certain species, a considerable extent of individuals get back to similar breeding, overwintering, and stopover areas in progressive years. This review proposes that migratory birds have advanced uncommon cognitive capacities that empower them to achieve these accomplishments.      

The Initial Orientation of Homing Pigeons at the Magnetic Equator: Compass Mechanisms and the Effect of Applied Magnets

1991 ◽  
Vol 161 (1) ◽  
pp. 299-314
Author(s):  
RONALD RANVAUD ◽  
KLAUS SCHMIDT-KOENIG ◽  
JÖRG U. GANZHORN ◽  
JAKOB KIEPENHEUER ◽  
ODIVAL C. GASPAROTTO ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Migratory Birds ◽  
Sensory System ◽  
Magnetic Equator ◽  
The Sun ◽  
Sun Compass ◽  
Homing Pigeons ◽  
Directional Preference ◽  
Compass Mechanisms ◽  
Inclination Compass

Homing pigeons are thought to use the earth's magnetic field for direction finding. Though the sensory system and the characteristics of the magnetic field used are unknown, it can be hypothesized that pigeons have an inclination compass, as do some migratory birds. When released at the magnetic equator, this inclination compass ought to be suspended. In addition, releasing pigeons when the sun is at or very close to the zenith renders the sun compass inoperational. However, released under these conditions, homing pigeons are not disorientated. Though they vanish on average in a different direction from pigeons released when the sun compass is available, they still show a directional preference close to magnetic north. This directional preference could be disrupted in some years by the application of magnets to the pigeons' back. In other years this treatment as well as another magnetic treatment did not produce any difference between experimental pigeons and controls. These results confirm once more that, if magnetic effects exist, they are of a rather discrete nature.

scholarly journals The magnetic compass mechanisms of birds and rodents are based on different physical principles

2006 ◽  
Vol 3 (9) ◽  
pp. 583-587 ◽  
Author(s):  
Peter Thalau ◽  
Thorsten Ritz ◽  
Hynek Burda ◽  
Regina E Wegner ◽  
Roswitha Wiltschko
Keyword(s):  
Geomagnetic Field ◽  
Migratory Birds ◽  
Radical Pair ◽  
Broad Band ◽  
Static Field ◽  
Magnetic Compass ◽  
Radical Pair Mechanism ◽  
Zeeman Frequency ◽  
Compass Mechanisms ◽  
Physical Principles

Recently, oscillating magnetic fields in the MHz-range were introduced as a useful diagnostic tool to identify the mechanism underlying magnetoreception. The effect of very weak high-frequency fields on the orientation of migratory birds indicates that the avian magnetic compass is based on a radical pair mechanism. To analyse the nature of the magnetic compass of mammals, we tested rodents, Ansell's mole-rats, using their tendency to build their nests in the southern part of the arena as a criterion whether or not they could orient. In contrast to birds, their orientation was not disrupted when a broad-band field of 0.1–10 MHz of 85 nT or a 1.315 MHz field of 480 nT was added to the static geomagnetic field of 46 000 nT. Even increasing the intensity of the 1.315 MHz field (Zeeman frequency in the local geomagnetic field) to 4800 nT, more than a tenth of the static field, the mole-rats remained unaffected and continued to build their nests in the south. These results indicate that in contrast to that of birds, their magnetic compass does not involve radical pair processes; it seems to be based on a fundamentally different principle, which probably involves magnetite.

scholarly journals Perancangan Desain User Interface Aplikasi KABITA Untuk Menginformasikan Kuliner Street Food Kota BandungTION TO INFORM INFORMATION STREET FOOD CULINARY BANDUNG CITY

2020 ◽  
Vol 3 (1) ◽  
pp. 26-40
Author(s):  
Diwan Setiawan ◽  
Sri Wulandari
Keyword(s):  
User Interface ◽  
Interface Design ◽  
Rapid Development ◽  
Field Studies ◽  
Street Food ◽  
City Street ◽  
Long Time ◽  
The Media ◽  
Information Media ◽  
The City

Bandung is a city that has a variety of culinary, it makes this city as a culinary tourism destination that highly demanded by both domestic and foreign tourists. Based on data from the Department of Culture and Tourism of Bandung, Bandung has a legendary street food culinary that is highly favored by culinary enthusiasts who visit this city. Street food culinary is snacks that have been around for a long time with authentic flavors and stories behind, some of popular street food culinary are bandros, combro, colenak, ketan bakar, cireng ​​and others. The rapid development of culinary potential in this city has caused many new street foods that enriches culinary diversity in Bandung so that culinary enthusiasts need an information media contains of information about culinary in this city, especially authentic street food culinary which is starting to be hard to find. Through qualitative methods and data collection techniques by means of field studies such as observation, interviews and questionnaires, it is necessary to design an application-based information media. The final results of this research is user interface design for the media that informs Bandung street food culinary. Inspired by the word kabita which comes from Sundanese means tempted to taste food, was chosen as the name of the application that informs culinary street food in the city of Bandung that aims to facilitate culinary enthusiasts to get that information

Nomenclatural and taxonomic notes on Rubus sect. Corylifolii (Rosaceae) in Central Europe

Phytotaxa ◽  
2019 ◽  
Vol 388 (1) ◽  
pp. 107 ◽  
Author(s):  
GERGELY KIRÁLY
Keyword(s):  
Central Europe ◽  
Field Studies ◽  
Morphological Characterization ◽  
Type Material ◽  
Original Material ◽  
Long Time ◽  
The Alps ◽  
Locus Classicus

During recent herbarium and field studies three names of Rubus sect. Corylifolii ser. Subcanescentes were re-assessed. Rubus macrostemonides was typified with a neotype specimen from Salzburg (Austria), and its identity with R. baruthicus was shown (the previous name has the priority). Its presence at the Austrian locus classicus was confirmed also recently, this locality represents the easternmost occurrence of the species. The name R. holosericeus was (mis)applied for a long time for a widespread taxon occurring southeast of the Alps that is not at all present in the original material. This name was lectotypified with a specimen from Styria (Austria) here as a hitherto overlooked regional species recently recorded in Austria, Hungary and Slovenia. The taxon that was formerly (mis)identified as R. holosericeus has proven to be identical to R. semitomentosus, which is lectotypified here with a specimen from Hungary. For both taxa clarified here is, beside a circumstantial assessment of the type material, an improved morphological characterization and circumscription of distribution and habitats presented.

scholarly journals Climate change relaxes the time constraints for late-born offspring in a long-distance migrant

2016 ◽  
Vol 283 (1839) ◽  
pp. 20161366 ◽  
Author(s):  
Barbara M. Tomotani ◽  
Phillip Gienapp ◽  
Domien G. M. Beersma ◽  
Marcel E. Visser
Keyword(s):  
Climate Change ◽  
Annual Cycle ◽  
Migratory Birds ◽  
Climate Change Impacts ◽  
Egg Laying ◽  
Time Constraints ◽  
Long Distance ◽  
Hatch Date ◽  
Breeding Bird ◽  
And Migration

Animals in seasonal environments need to fit their annual-cycle stages, such as moult and migration, in a tight schedule. Climate change affects the phenology of organisms and causes advancements in timing of these annual-cycle stages but not necessarily at the same rates. For migratory birds, this can lead to more severe or more relaxed time constraints in the time from fledging to migration, depending on the relative shifts of the different stages. We tested how a shift in hatch date, which has advanced due to climate change, impacts the organization of the birds' whole annual cycle. We experimentally advanced and delayed the hatch date of pied flycatcher chicks in the field and then measured the timing of their annual-cycle stages in a controlled laboratory environment. Hatch date affected the timing of moult and pre-migratory fattening, but not migration. Early-born birds hence had a longer time to fatten up than late-born ones; the latter reduced their interval between onset of fattening and migration to be able to migrate at the same time as the early-born birds. This difference in time constraints for early- and late-born individuals may explain why early-born offspring have a higher probability to recruit as a breeding bird. Climate change-associated advancements of avian egg-lay dates, which in turn advances hatch dates, can thus reduce the negative fitness consequences of reproducing late, thereby reducing the selection for early egg-laying migratory birds.

scholarly journals Electron spin relaxation in cryptochrome-based magnetoreception

2016 ◽  
Vol 18 (18) ◽  
pp. 12443-12456 ◽  
Author(s):  
Daniel R. Kattnig ◽  
Ilia A. Solov'yov ◽  
P. J. Hore
Keyword(s):  
Protein Dynamics ◽  
Spin Relaxation ◽  
Electron Spin ◽  
Migratory Birds ◽  
Magnetic Compass ◽  
Radical Pairs ◽  
Electron Spin Relaxation ◽  
The Impact

The magnetic compass sense of migratory birds is thought to rely on magnetically sensitive radical pairs formed photochemically in cryptochrome proteins in the retina. Here we assess the impact of protein dynamics on the sensitivity of the compass.

Pingo collapse and paleoclimatic reconstruction

1988 ◽  
Vol 25 (4) ◽  
pp. 495-511 ◽  
Author(s):  
J. Ross Mackay
Keyword(s):  
Soviet Union ◽  
Field Studies ◽  
Normal Faults ◽  
Paleoclimatic Reconstruction ◽  
Air Temperatures ◽  
The Soviet Union ◽  
Long Time ◽  
Western Arctic ◽  
Arctic Coast ◽  
Time Required

Long-term field studies of contemporary pingo growth, collapse, and rampart formation along the western Arctic coast of Canada provide criteria that may be helpful in the identification of pingo ramparts in nonpermafrost environments. Such criteria include the volume of the ramparts, which should approximate that of the enclosed depressions from which the rampart materials were derived; peripheral deposits associated with mass wasting, streamflow, and debris flow; casts of dilation crack ice trending across the ramparts; and high-angle peripheral normal faults. The conventional method of correlating the present mean annual air temperature with the present pingo distribution to establish warm-side limiting temperatures for paleoclimatic reconstruction is unsound, because most pingos in North America and the Soviet Union commenced growth hundreds to thousands of years ago under mean annual air temperatures that may have differed greatly from those of the present. Some other factors to be considered in paleoclimatic reconstruction are the thermal offset; site availability; the differing requirements for the growth of large pingos as compared with small pingos; and the long time required for pingos to grow to full size.

scholarly journals ANALISIS PERLAKUAN PAJAK PERTAMBAHAN NILAI ATAS AKAD MURABAHAH

2016 ◽  
Vol 6 (2) ◽  
pp. 227
Author(s):  
Laili Farihah ◽  
Sri Andriani
Keyword(s):  
Value Added ◽  
Secondary Data ◽  
Field Studies ◽  
Director General ◽  
Islamic Banks ◽  
Data Field ◽  
Before And After ◽  
Long Time ◽  
Descriptive Approach ◽  
Government Legislation

<p><strong>Abstract</strong><br /><br />Murabahah contract is one of the products of Islamic banks before 1 April 2010 subject to twice the value-added tax. Problems of double taxation is imposed on Islamic banks actually issue a very long time, and this bustling discussed tax due to be paid twice to the director general of a larger tax. By this provisions, the sharia will be assumed less competitive with conventional bank financing primarily to the product. After government legislation latest VAT No. 42 of 2010, murabahah is not longer subject to twice. Investigators therefore conducted an analyze on the treatment of KCS Bank BTN Shariah Malang. This research is using research of qualitative in descriptive approach, which describes a situation systematically. The data uses both the primary and secondary data, field studies with research techniques are interview and documentation. The results showed that the Bank BTN Shariah Malang KCS on contract murabahah charged once before and after running of the No. 42 of 2009 rule.</p><p><strong>Abstrak</strong><br /><br />Akad murabahah merupakan salah satu produk dari bank syariah yang sebelum 1 April 2010 dikenakan dua kali pajak pertambahan nilai. Permasalahan pajak berganda yang dikenakan kepada bank syariah sebenarnya sudah isu yang sangat lama, dan saat ini kembali ramai diberdebatkan lantaran pajak yang harus dibayarkan kepada dirjen pajak lebih besar. Dengan ketentuan yang seperti ini, pihak syariah akan menganggap kalah saing dengan bank konvensional denan produk pembiayaannya. Setelah pemerintah undang-uundang PPN terbaru no 42 tahun 2010, akad murabahah tidak lagi dikenakan dua kali PPN. Oleh karena itu peneliti melakukan analisis perlakuan PPN pada Bank BTN Syariah KCS Malang. Penelitian ini merupakan jenis penelitian kuaitatif dengan pendekatan deskriptif, yaitu menjabarkan suatu situasi secara sistematis. Data yang digunakan adalah data primer dan skunder, dengan teknik penelitian studi lapangan yaitu wawancara dandokumentasi. Dari hasil penelitian menunjukkan bahwa Bank BTN Syariah KCS Malang atas akad murabahahnya dikenakan satu kali PPN sebelum dan sesudah UU no 42 tahun 2009.</p>

scholarly journals Does migration influence corruption in Europe?

2019 ◽  
Vol 13 (1) ◽  
pp. 468-478
Author(s):  
Liviu-Stelian Begu ◽  
Adriana AnaMaria Davidescu ◽  
Simona-Andreea Apostu ◽  
Andreea-Oana Enache
Keyword(s):  
Economic Factors ◽  
Panel Regression ◽  
European Level ◽  
Statistical Software ◽  
Country Level ◽  
Long Time ◽  
Corruption Perception ◽  
And Cluster Analysis ◽  
And Migration ◽  
Over Time

Abstract Corruption and migration influence the country level of development, so they have been debated and studied for a long time. Has been written a lot about the two phenomena and their relations with many social and economic factors, but the two also influence each other. The higher the level of corruption in a country, the more people will be more likely to migrate and vice versa. This study aims to study the link between the two phenomena considering the countries from Europe, over time, for the period 2008-2016, highlighting the implications in the economy. The variables analyzed are the Corruption Perception Index and the number of emigrants. The methods used are panel regression and cluster analysis and the processing and analysis was performed using the statistical software SAS (version 9.2) and SPSS (version 13 and 25). The findings show that there is a link at European level between the two phenomena, corruption and migration have a similar trend over time, and significant differences are registered between countries.

scholarly journals A full annual perspective on sex-biased migration timing in long-distance migratory birds

2019 ◽  
Vol 286 (1897) ◽  
pp. 20182821 ◽  
Author(s):  
Martins Briedis ◽  
Silke Bauer ◽  
Peter Adamík ◽  
José A. Alves ◽  
Joana S. Costa ◽  
...  
Keyword(s):  
Annual Cycle ◽  
Migratory Birds ◽  
Long Distance ◽  
Breeding Sites ◽  
Arrival Times ◽  
Migration Timing ◽  
Female Migration ◽  
Proximate Determinants ◽  
Carry Over ◽  
And Migration

In many taxa, the most common form of sex-biased migration timing is protandry—the earlier arrival of males at breeding areas. Here we test this concept across the annual cycle of long-distance migratory birds. Using more than 350 migration tracks of small-bodied trans-Saharan migrants, we quantify differences in male and female migration schedules and test for proximate determinants of sex-specific timing. In autumn, males started migration about 2 days earlier, but this difference did not carry over to arrival at the non-breeding sites. In spring, males on average departed from the African non-breeding sites about 3 days earlier and reached breeding sitesca4 days ahead of females. A cross-species comparison revealed large variation in the level of protandry and protogyny across the annual cycle. While we found tight links between individual timing of departure and arrival within each migration season, only for males the timing of spring migration was linked to the timing of previous autumn migration. In conclusion, our results demonstrate that protandry is not exclusively a reproductive strategy but rather occurs year-round and the two main proximate determinants for the magnitude of sex-biased arrival times in autumn and spring are sex-specific differences in departure timing and migration duration.

Sign in / Sign up

Export Citation Format

Share Document