In ecology<span>, a </span>niche<span> (</span>CanE<span>, </span><span><span>UK:</span> <span>/<span>ˈniːʃ</span>/</span></span><span> or </span><span><span>US:</span> <span>/<span>ˈnɪtʃ</span>/</span></span>)[1] is the fit of a species living under specific environmental conditions.
<span>https://en.wikipedia.org/wiki/Ecological_niche</span>
        
                    
             
        
        
        
<span>The reaction required an input of energy.</span>
        
                    
             
        
        
        
The only competitors that humans have for food are other humans and insects: Agree; we do compete with other animals for food
<u>Explanation:</u>
The term competitor is used to describe interaction that takes place within any two organisms as a result of which both the organisms are affected. The functional role that an organism have within the environment is known as Niche.
Parasitism refers to the interaction that takes place between any two organisms or species as a result of which only one will get benefits and the other one will be getting affected.In an ecosystem, every organism strives hard for living and need food for its survival. Hence, the competitors for food in an ecosystem will be other human, insects, animals, etc.
 
        
             
        
        
        
<span>The mouse and rabbit both have a competitive relationship. They both have a place in a similar class. They are in the group of mammalia. There are environmental connections of which two are oppositional and four are harmonious. The oppositional connections are predation and rivalry.</span>