Butterflies ~ TY



Butterflies are insects belonging to the order of Lepidoptera (Latin for ‘scaly wing’) which feed primarily on nectar from flowers. They are very important pollinators for some species of plants but they are not able to carry as much pollen as bees can. They are found all over the world and may migrate in order to avoid adverse environment conditions.

Butterflies are ectotherms, which mean that they gain heat from their environment. If they are too cold they cannot fly. If they get too hot they become dehydrated and die, and they can only fly when their body temperature is between 75oC– 90oC. Therefore they use behavioural methods in order to help control their temperature.

Adult butterflies exhibit three thermoregulatory mechanisms - dorsal, lateral and reflectance basking.

In cool conditions butterflies need to raise their body temperatures before they are able to fly. To do so they use a technique known as dorsal basking, whereby they use the upper surface of their wings to absorb heat from the sun and thus gain energy.

Some butterflies, such as Green Hairstreaks, always keep their wings closed when at rest, and adopt another technique known as lateral basking. In cool conditions they bask by tilting their wings over to one side, so as to present the maximum area of wing surface to the sun. Therefore, when it gets too hot, they tilt in the opposite direction so that their wing surfaces are parallel to the sun's rays, and present the minimum surface area to the sun. When it gets too hot they also tend to hide beneath leaves and seek shade.

Some butterflies have wing surfaces which reflect solar energy. The mechanism used by these butterflies is called reflectance basking.