Summary Use a magnet to separate grains of magnetite from beach sand. Can be used to discuss how magneto reception might work. Science content Biology: Sensing, Organ Systems (4, 5, 6) Earth/Space: Rock cycle, Earth Materials, Natural resources (5) Lessons activity is in Animal senses Beach Exploration and Studies Materials small ziplock baggies beach sand containing magnetite e.g. Vancouver beaches magnets Procedure If sand gets on the magnet, it is hard to remove, so: either put a magnet in a baggie, then move it over a pile of sand, or put some sand in a baggie, then move the magnet over it. The magnetite grains in the sand will be strongly attracted to the magnet. Using the magnet, the dark grey magnetite grains can be separated from the rest of the rock types in the sand. Magnetite is a mineral containing iron. It is the most magnetic of all naturally occuring minerals on Earth. Small grains of magnetite are very common in igneous and metamorphic rocks. Discussion on magneto reception in animals: Bees, as well as bacteria and many migrating animals like birds and turtles can sense the Earth’s magnetic field and the patterns it makes. They use it to migrate with the seasons, and to map and find their breeding and feeding grounds. Bird migration map: Bird migration: https://www.allaboutbirds.org/news/mesmerizing-migration-watch-118-bird… We don’t know exactly how magneto reception works - we are still researching how. One theory is that the tiny magnetite particles found in some animals (in bird beaks and fish noses) are attracted to the magnetic field of the Earth. The magnetite signals which way is North, and is also sensitive to the variation in magnetic field strength in different places across the Earth. Another theory involves a protein in the retina of animals' eyes. Magneto reception is found in these animals: arthropods incl. insects - honey bee, fruit fly, ants molluscs - sea slug fish - salmon amphibians - salamander, newt reptiles - turtles birds - canada geese etc etc mammals - brown bat humans - we don’t know of a behavioural change, but an affect on our alpha brain waves has been found Grades taught Gr 4 Gr 5
