What type of fossil evidence may exist that would lead scientists to believe that dinosaurs were ancestors of birds? why might large dinosaurs have died out at the end of the mesozoic era, while smaller birds survived?

common management practices in dairy and poultry farming are: (i) proper shelter facilities and their regular cleaning. (ii) some basic hygienic conditions such as clean water, nutritious food, etc. (iii) animals are kept in spacious, airy, and ventilated place.