It gets bigger at puberty, and then slowly shrinks with age.
Probably not, especially if the brown line is constant and does not change over time.
You don't say which speed, but all change over time.
False. Acceleration is a change of speed or direction over time.
Velocity.
evolution
Probably not, especially if the brown line is constant and does not change over time.
The sensitivity of the penis can be affected if a person has masturbated frequently over the course of time. This can be improved by limiting masturbation and using more lubricant when masturbating. It won't change overnight, but over time a person should experience more sensation.
Hopefully, nothing dangerous.
The last time that I checked, I didn't find any species of animal with a detachable penis. There are animal's that can change sex in the right conditions (amphibians) but none that break off their sexual organ to loan to a female.
Assuming you're a male, just lay there with your penis in him/her and don't move.
A barbed penis is the external male reproductive organ with a particular structure at the base that looks like a "barb" or a spiny projection. In cats, this barb keeps the male and the female together until the male's sperm has time to fertilize the female's eggs.
How have valleys change over time?How have valleys change over time?How have valleys change over time?
How did the dirction of the moon change over time? How did the dirction of the moon change over time?
A change over time is often referred to as a gradual change.
All the time ! Exaggeration of penis size is very common the world over. It is one of the insecurities of man.
Most penis growth is completed by the time the male reaches sixteen or seventeen, so generally the difference is not incredibly noticeable from sixteen years old to adult, but they are different factors that change this like when the boy started puberty, etc.