Preferential temperature in insects

Principle

The temperature requirements of animals with regard to their environment differ widely: they vary from temperatures just below 0°C for arctic and antarctic animals to temperatures of around 50°C for desert animals and animals from hot springs. Within these limits many species prefer one range: the preferential temperature. Using their thermoreceptors the animals recognize the temperature which suits them, gather in an area at the corresponding temperature (thermotaxis) and thus show their preferred temperature.

Benefits

• Precise measurement possible with 12 different temperature zones
• Allows to set up a wide temperature range
• In the ring-shaped measurement setup the animals can migrate in both directions at each measurement point
• Experimental setup can also be used for plant growth experiments

Tasks

1. Test the temperature demands of different poikilothermic animal species
2. Produce a temperature gradient between approximately 45°C and 10°C using a ring-shaped temperature organ
3. Record the positions of the individual animals

Learning objectives

• Temperature optimum
• Poikilothermic animals
• Thermotaxis
• Phototaxis
• Thigmotaxis
• Torpor
• Environmental requirements
• Geographical seperation