Lesson plan

Animal senses

Summary
Activities on animal senses that are weak or absent in humans: echolocation, seeing in ultra violet and infra red, magnetoreception.
Science content
Biology: Features, Adaptations of Living Things (K, 1, 3, 7)
Biology: Classification of Living Things, Biodiversity (1, 3)
Biology: Sensing, Organ Systems (4, 5, 6)
Procedure

A series of activities exploring different kinds of animal sensing.
The first three can be stations to rotate through, one half of the class doing 'Ir detection", while the other half is split betweebn 'UV detection' and 'Magneto reception' activities; then switch.
The final two activities need to be done as a class.

UV detection
UV patterns in flowers is a puzzle, showing the ultra violet pattern that bees can see in flowers.
The UV pattern often emphasizes the centre of the flower where the nectar is.

Magneto reception
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, to migrate with the seasons, and to map and find their breeding and feeding grounds.
Bird migration active map: https://www.allaboutbirds.org/news/mesmerizing-migration-watch-118-bird…
We don’t know exactly how they do it - we are still learning.
One way of detecting magnetic fields uses a mineral (a part of a rock) called magnetite.
Students find magnetite in beach sand using a magnet.

IR detection
At the other end of the light spectrum is Infra red, which we sense on our skin (as warmth).
Some snakes, the pit vipers (pythons, boas, and rattlesnakes) have special pit organs. They can detect changes in 0.002-0.003 degrees C, 10X our sensitivity.
We have tools that can help us see where heat is coming from.
Students look at the images from IR cameras - search for 'infra red images' to find many online.
Experiment with heat sensitive paper - it shows temperature change by turning colours.
Students use the heat of their hand or use IR radiation from the bulb (don't touch the bulb), to make the sheets turn colours and indicate how much heat is hitting them.

Ultrasound and infrasound
Use a tone generator to show how different people in the classroom detect different sound frequencies People can hear between 20Hz and 20,000Hz. Younger people can hear higher frequencies.
Some animals can hear above us (called 'ultrasound' and is above 20,000Hz). Dolphins can hear as high as 150,000Hz. Bats hear as high as 120,000Hz.
Some animals can hear lower than us ('infrasound', lower than 20Hz). Elephants can hear as low as 5Hz

Echolocation
Some animals use sound bouncing off objects to map the world around them and catch food.
Bats, dolphins and whales, birds that live in caves (kind of swift), shrews.
People have tools to echolocate, like sonar (to map underwater) [radar is an electromagnetic wave].
Some blind people ‘click’ and echolocate.
Go outside to bounce sound off a wall, to show how echolocation works.

Grades taught
Gr 4