Parasites need a host. If a host tries to get rid of the parasite or kill it, then the parasite either has to leave the body or die.
I think it is keystone. If they were not there the population of urchins would go up and the kelp would go down.
Each parent contributes one allele for this trait.
An operational definition is used for a behavior so that the
behavior can be properly described and understood. Without an operational
definition, it would be difficult to describe behavior without being subjective.
Therefore, behavior cannot be understood and cannot be correctly addressed. It
is also important to understand how behavior functions so that the antecedents
and consequences of behavior can be observed. Thus, what reinforces or affects the
behavior can be better understood. Lastly, an operational definition is
objective and specific, therefore, behavior can be described across different
settings and times.
