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Difference between revisions of "Antarctic midge"
added link to psychrophiles
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==Tolerance to extreme cold== | ==Tolerance to extreme cold== | ||
The flightlessness of of the Antarctic midge may be an adaptation to prevent wind from blowing it into inhospitable areas. | The flightlessness of of the Antarctic midge may be an adaptation to prevent wind from blowing it into inhospitable areas. As a [[psychrophiles|psychrophile]], it can survive freezing, but despite air temperatures reaching as low as -40 °C, this insect will not be alive after temperature drops under -15 °C. This is less than other cold-adapted insects. The reason for this comparatively low freezing tolerance is due to thermal buffering: just burrowing at a depth of 1 cm, temperature is stable between 0 and -2 °C for 10 months out of 12, and it seldom goes lower than -7 °C all year round. [[Ice]] and snow cover also helps keeping the temperature stable. Freezing tolerance is enhanced by cold hardening. | ||
To adapt to the cold temperatures, the Antarctic midge accumulates trehalose, glucose, and erythritol. These compounds help the insect survive freezing by reducing the amount of ice that forms within the body. They also stabilize proteins and membranes, binding to them by means of hydrogen bonds. Heat shock proteins also help the tolerance to both high and low temperatures. | To adapt to the cold temperatures, the Antarctic midge accumulates trehalose, glucose, and erythritol. These compounds help the insect survive freezing by reducing the amount of ice that forms within the body. They also stabilize proteins and membranes, binding to them by means of hydrogen bonds. Heat shock proteins also help the tolerance to both high and low temperatures. | ||