a serious disagreement

the way someone acts

A feeling of being excited about something is being aggressive

wanting to be successful

to speak badly of someone or something

  to look after someone (usually a young, sick or old person)

to  interact is to communicate with someone or something 

Usually  also means

to notice something new or different instead of the original

to train someone to follow rules or codes of behavior

previously means before the time period that you are talking about

To replace is to have something old

the characteristic of being male or female

Primatologists are experts who study the behavior of primates in their habitats