Dear WW: All the biting insects have one thing in common. The remales need extra
protein to lay eggs. Most get it from animal blood. They differ widely in the way
they get the blood. The mosquitoes are almost unique in having a long device to
penetrate skin. It is made up of three needles that can move forward and back
independently to facilitate penetration. Capillary attraction makes blood climb up
so mosquito can ingest it. All of the biting insects use an anticoagulant so clotting
cannot interfere with their meal. Sensitivity to the anticoagulant is what makes
bites later itch and swell up.
For most of their lives mosquitoes feed on plant fluids. And remember, it is only
the dad-ratted females that bite.