About 46 million years ago, a mosquito sunk its proboscis into some animal, perhaps a bird or a mammal, and filled up on a meal of blood. Then its luck turned for the worse, as it fell into a lake and ...

In some women, a few days after delivery the milk supply comes on so quickly that the breasts become swollen, hard and sore. This is called engorgement. There is an increased supply of blood and other ...