|
|
About 3.2 billion people, nearly half the world population, are at risk for malaria. In 2015, there are about 214 million malaria cases and an estimated 438,000 malaria deaths.
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.
Although puberty usually occurs in the early teenage years, the world's youngest parents were two Chinese children who had their first baby when they were 8 and 9 years of age.
In 1886, William Bates reported on the discovery of a substance produced by the adrenal gland that turned out to be epinephrine (adrenaline). In 1904, this drug was first artificially synthesized by Friedrich Stolz.
![Zebras are several species of African equids (horse family) united by their distinctive black and wh](https://biology-forums.com/gallery/47/medium_27759_23_04_12_6_59_00.jpeg)
![The Canadian ballot is considerably simpler than the American ballot. Note there is nothing like a c](https://biology-forums.com/gallery/47/medium_262797_12_08_15_1_37_19_221871018.png)