Biological theories of aggression suggest that aggressive behavior is influenced by genetic, neurological, and hormonal factors. Research indicates that certain genes may predispose individuals to aggressive tendencies, while brain structures like the amygdala play a crucial role in processing emotions related to aggression. Additionally, neurotransmitters such as serotonin and dopamine are linked to mood regulation and can affect aggressive behavior. Hormones, particularly testosterone, have also been associated with aggression. Studies show that higher levels of testosterone may correlate with increased aggressive behavior in both animals and humans. Overall, biological theories emphasize the interplay between genetics, brain function, and hormonal influences in understanding aggression.