Mystery #58

I have killed more people than every war put together, and I am not even trying to.

The first of five clues. Each one below gives a little more away.

1

I have killed more people than every war put together, and I am not even trying to.

2

Only half of us bite, and not for food.

3

I find you by the carbon dioxide you breathe out, from many metres away.

4

The itch is not from the bite. It is your own body reacting to my saliva.

5

The whine in the dark and the bump in the morning.

The answer

Mosquito

Only the females take blood, and not to feed themselves — they need the protein to develop eggs. Their actual food is nectar, the same as a bee's.

Malaria alone is estimated to have killed more human beings than any other single cause, and the mosquito is the vector for that plus dengue, yellow fever, Zika and several encephalitides. Only females bite, and not for nourishment — both sexes live on nectar — but because egg development requires protein from blood. They locate a target by carbon dioxide from tens of metres away, then close in on body heat, sweat chemistry and skin bacteria. The bite itself is painless; the welt is an immune reaction to the anticoagulant saliva injected to keep the blood flowing.

Play it properly

Reading five clues at once is not the game. In the real thing they arrive one at a time and every wrong guess costs an hour. Play mystery #58 · today's mystery · the vault

Nearby mysteries

Previous: mystery #57. Next: mystery #59. Or try #29, #30, #31, #32, #33, #34.