But the question remains: why do the little pests take our blood in the first place?
A = “no” or “not”
Auto = “self”
Geny = “generation”
When you put it together, it becomes “not able to self-generate.” But this is still sort of vague. Generate what? And if they can’t do it by themselves, what do they need?
In mosquitoes, the greenhead fly, and no-see-ums, only the females are equipped to draw blood. The males get all of their nourishment from other sources, usually flower nectar or other juices.
The females can support themselves that way, but not their eggs. They don’t produce enough of certain nutrients – generally protein – to have enough energy to develop eggs on their own. The female mosquitos, greenheads, etc. take blood from vertebrates so their bodies can form eggs. This extra caloric intake goes straight to the yolks, which the insect’s embryos then use as a food source as they develop. This process of requiring a particular meal (such as blood) in order to lay eggs is called anautogeny.
Next time you are mauled by mosquitoes, gobbed by a greenhead, or gnawed by a no-see-um, know that your blood is going on to nourish the next generation of anautogenic monstrosities.