Answer:
In the course of evolution mammals are the animals which are evolved recently as compared to other groups such as fish, amphibians, or reptiles.
In addition, fur or hairs on body, mammary glands, middle ear bone, warm-blood, et cetera are the characteristics of mammals.
These characteristics were evolved during the course of evolution; they were not present in ancestral organisms.
However, tail, gill pouches, et cetera are characteristics of our ancestral groups. Thus, characters can be sometimes observed in mammals.
But mammals characteristics can not be observed in organisms which were evolved before mammals such as fishes, amphibians, reptiles, et cetera.
 
        
             
        
        
        
Chloroplasts are organelles found in plant cells that conduct photosynthesis. Chloroplasts absorb light and use it in conjunction with water and carbon dioxide gas to produce food for the plant.
        
             
        
        
        
Answer:
...were due to single genes and followed simple inheritance patterns (dominant/recessive).
Explanation:
The traits Mendel studied were easy to track because the two possible outcomes were distinct and the trait itself was visible and trackable.  The fact that they followed simple inheritance patterns helped him when he was determining his ratios for different crosses because complex inheritance would've muddled his data.
 
        
             
        
        
        
By performing this dance, successful foragers can share, with other members of the colony<span>, information about the direction and distance to patches of flowers yielding nectar and pollen, to water sources, or to new nest-site locations.</span>