|
|
When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
During the twentieth century, a variant of the metric system was used in Russia and France in which the base unit of mass was the tonne. Instead of kilograms, this system used millitonnes (mt).
Asthma cases in Americans are about 75% higher today than they were in 1980.
Chronic marijuana use can damage the white blood cells and reduce the immune system's ability to respond to disease by as much as 40%. Without a strong immune system, the body is vulnerable to all kinds of degenerative and infectious diseases.
![Rates of water loss by two turtles and a tortoise indicate an inverse relationship between the dryne](https://biology-forums.com/gallery/47/medium_33_08_09_11_10_42_35_16841686.jpeg)
![While numerous subspecies of the jaguar have been recognized, recent research suggests just three. G](https://biology-forums.com/gallery/47/medium_27638_22_04_12_9_37_20.jpeg)