How, why, and at want stage in their ancestry, did mammalian bladders evolve ? clearly, as things are, we would find it unpleasant to leak continually. But we would know no different if we never had one. If there were continual leaking, prey animals would leave a trail and preditors could not mark territory.  As ever "What use is half a bladder ?"

Tsunamis move fast, and tow-in surfers use various vehicles to catch large waves. A friend has a son who wants to ride a 100-foot wave. Is this possible? How big of a wave could an unassisted surfer catch?

Everyone has died so far, but people wonder if things are speeded up unnecessarily. Some claim that isolated Eskimos a century ago had "perfect" hearing at age sixty, but the introduction of snowmobiles and rifles led to most being deaf by the same age a generation or two later.

How does exposure to sunlight (with and without sunglasses) affect vision? How do other animals fare?

It's claimed by some that eyes are diffraction limited at the small end. Are there any upper limits on the size of animal eyes?

Giant squid aside, how do eyes scale with body size?

As a correction to this question, some argue that the (non-compound) eye might have originally evolved as a "camera obscura" with a pinhole lens; more complex lenses may have then followed. Is there any physical limit on a pinhole lens that might have (historically) limited the size of an eye?

Does being able to get by on little sleep correlate with any characteristics?

When I eat certain cheeses (especially strong cheddar and old gouda), immediately after swallowing and before it reaches my stomach I get a strange sensation on my upper cheeks.

I feel a tingle and if i go for a second mouthful I get the sensation of sweating and very fine beads of sweat appear.

Why does it happen? Is it a tyramine response? Why is it so localised? - the location reminds me of a picture from an old anatomy textbook that described the position of the sensors on the face responsible for initiating the dive reflex.

I have very vivid dreams where I can in detail, see or visualise my complete surroundings.

If a person was born blind what would they dream of?

Also, If a person lost there sight later in life, would their lack of vision while they were blind effect what they experience dreams?