They saw how smoking effected the body since smoking was pushed as something good for a long time, a lot of people started smoking and after a few years doctors finally saw a difference between a smokers body and a non smokers body
        
             
        
        
        
Biomes are typically defined<span> by their climate and dominant vegetation, including grassland, tundra, desert, tropical rainforest, and deciduous and coniferous forests.</span>
        
             
        
        
        
Archaeopteryx had "teeth, three claws on each wing" similar to dinosaurs. So, most appropriate answer would be Teeth & Wings
Hope this helps!