4. Why do you think some birds have wings but cannot fly? Some of the birds a. are half breed b. are featherless are too heavy to fly d. wings are not big enough 5. Which description is TRUE about amphibians? a. They do not develop any lungs. b. They lack legs during their cycle. c. When they are young, they breathe on their gills. d. They cannot live in land but they can live in water.