... and most SCUBA equipment functions relatively well when immersed in human blood. However, since the density of blood (1.06 kg/L) is much higher than fresh water (1.00 kg/L) and slightly higher than seawater (1.03 kg/L), SCUBA diving weights must be adjusted. For obvious reasons, most equipment manufactured after 2006 is designed to cope with this ...

... we've all heard the factoid that the average person supposedly eats 4 spiders per second. This statistic is misleading; it's based on a study examining on the peak rate of spider consumption in areas where the spider-streams are densest. The global average rate is probably closer to 1 spider per second (obviously higher while asleep than while awake) ...

... assuming American football has an average death rate of 1.2 players per game. This is slightly higher than the average for association football (soccer), but an order of magnitude lower than the rates found in volleyball.

... the concept of a "population bottleneck" is in the news a lot lately. Let's take a look at some examples of past human population bottlenecks, which should help us understand how the current situation is both qualitatively different and much worse than ...

According to a report by the Occupational Safety & Health Administration, the top ten leading causes of injury in the workplace are as follows:

• • Lightning strikes
• • Unknown
• • Predation
• • Betrayal
• • Curses (ancient + modern)
• • Ant bites
• • Falling
• • Spider bites
• • Bites (other)
• • Natural causes

... while the idea that a human-sized mirror could offer protection from moonlight makes intuitive sense, in effect it serves only to create a second moon. The interaction between any pair of moons—in this case, the real Moon and the mirror-image "virtual" Moon—takes place at the geometric halfway point between them.

Here, that point is located at the surface of the mirror you are carrying, which makes it clear why this is such a bad ...

... while there are no firsthand accounts of the new building layout near Buckingham Palace, an examination of satellite imagery can give us an idea of the changes. Although the images are clearly heavily distorted due to the highly variable air temperature in Westminster, it appears that the Tower of London is intact, surrounded by a series of concentric rings presumably made from the remains of ...

... for these calculations, we will assume a spherical cow, although most remaining "cows" are actually closer to oblate spheroids ...

... while a roc is self-evidently capable of lifting and carrying adult humans without difficulty, even the largest among them would struggle to lift a typical 1,200 kg sedan. While it's plausible that a flock could accomplish this by cooperative lifting, they have instead taken to dropping boulders (usually 50-100 kg) on the cars from above. This is why most commuters stick to the tunnels, despite the obvious threat posed by snakes and ...