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Other Unique Bacteria

Other Unique Bacteria

Magnetic bacteria exhibit a directed movement called magnetotaxis, driven by structures called magnetosomes. These magnetosomes consist of chains of magnetic particles made of either magnetite (Fe₃O₄) or greigite (Fe₃S₄) and are organized in a linear conformation by a protein scaffold within invaginations of the cell membrane. The bacteria align along the north–south magnetic field lines, much like a compass needle. They are typically microaerophilic or anaerobic and are commonly found near the...

Magnetism

Magnetism

Magnets are commonly found in everyday objects, such as toys, hangers, elevators, doorbells, and computer devices. Experimentation on these magnets shows that all magnets have two poles: one is labeled north (N) and the other south (S). Magnetic poles repel if they are alike and attract if unlike. Moreover, both poles of a magnet attract unmagnetized pieces of iron.
An individual magnetic pole cannot be isolated. No matter how small, every piece of a magnet contains a north pole and a south...

Compass

Compass

The compass is a fundamental instrument that operates by aligning its magnetic needle with Earth's magnetic field. This alignment facilitates navigation and orientation, offering a means to determine direction relative to magnetic north. However, the magnetic needle points to magnetic north, which differs slightly from true geographic north due to magnetic declination, which is the angular deviation between these two points. Declination varies based on geographic location and shifts over time...

Magnetic Declination

Magnetic Declination

Magnetic declination is the angle between true north, which aligns with the Earth's rotational axis, and magnetic north, which follows the direction of the Earth's magnetic field. This discrepancy exists because the magnetic poles do not coincide with the geographic poles. The value of magnetic declination depends on the observer's location on Earth and is subject to changes over time due to the dynamic nature of the Earth's magnetic field.The declination is called eastern when magnetic north...

Magnetic Field Lines

Magnetic Field Lines

The representation of magnetic fields by magnetic field lines is very useful in visualizing the strength and direction of the magnetic field. Each of the magnetic field lines forms a closed loop. The field lines emerge from the north pole (N), loop around to the south pole (S), and continue through the bar magnet back to the north pole.
Magnetic field lines follow several hard-and-fast rules:

Local Attraction

Local Attraction

Local attraction refers to disturbances in compass readings caused by magnetic influences from nearby objects such as metal fences, buried pipes, vehicles, buildings, power lines, or natural iron ore deposits. Small items like wristwatches, steel tools, or belt buckles can also interfere with the compass by creating local magnetic fields that distort the Earth's natural magnetic field. These distortions lead to inaccurate readings, posing navigation and land surveying challenges.Local...

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Using Pharmacological Manipulation and High-precision Radio Telemetry to Study the Spatial Cognition in Free-ranging Animals

Using Pharmacological Manipulation and High-precision Radio Telemetry to Study the Spatial Cognition in Free-ranging Animals

Published on: November 6, 2016

Magnetic maps in animals: nature's GPS.

Kenneth J Lohmann¹, Catherine M F Lohmann, Nathan F Putman

¹Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA. klohmann@email.unc.edu

The Journal of Experimental Biology

|October 24, 2007

Summary

Animals use Earth's magnetic field for navigation. Beyond just direction, this magnetic map provides positional information for migration and reaching destinations, a widespread ability across diverse species.

Area of Science:

* Zoology
* Animal Behavior
* Biophysics

Background:

* Many animals utilize the Earth's magnetic field for orientation and navigation.
* Previous research primarily focused on the directional 'compass' sense derived from magnetic fields.
* The Earth's magnetic field offers predictable variations across the globe, suggesting potential for positional 'map' information.

Purpose of the Study:

* To explore the use of magnetic positional information in animal navigation.
* To investigate the characteristics and diversity of animal 'magnetic maps'.
* To understand how magnetic map information is integrated with navigational strategies.

Main Methods:

* Review of existing literature on magnetoreception and animal navigation.

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* Analysis of studies demonstrating magnetic map use in various species.

* Comparative analysis of different proposed magnetic map organizations.

Main Results:

* Evidence supports the use of magnetic positional information in diverse animals like sea turtles, newts, birds, and spiny lobsters.
* This magnetic map capability appears phylogenetically widespread and functions across various spatial scales.
* The organization of these magnetic maps is not fully understood and may differ significantly from human cartographic systems.

Conclusions:

* Animals possess sophisticated magnetic map systems for navigation, extending beyond simple directional cues.
* These systems are crucial for migratory pathways and homing behaviors.
* Further research is needed to fully characterize magnetic map structures and their integration with novel navigational strategies.