not showing any joy
A trait or characteristic about a person that is related to the way they socialize or present themselves. For example; extroversion is a basic social trait for extroverts.
Yes, the frizzle trait in chickens is an example of Pleiotropy.
A cultural trait is any trait of human activity acquired in social life that is transmitted through communication.
Your Height
Charateristics is a trait for example a mean trait
Doing mathematics is definitely a learned trait.
Alleles are the same trait
A discontinuous trait is the opposite of a continuous trait. They are "either/or" traits that do not have any range. An example would be the sex of an offspring, whereas an example of a continuous trait would be haircolor, where many options are available.
A character trait is basically the personality of someone. For example my character trait can be generous.
hairstyle
hairstyle
No, not unless you are ill.