The duck-billed platypus is considered a connecting link because it lays eggs like reptiles yet shows which mammalian features?

1. A connecting link shows characters of two different groups. 2. The platypus lays eggs, which is a reptilian character. 3. It also has mammary glands and hairs, which are mammalian characters. 4. This combination makes it a link between reptiles and mammals. 5. So the mammalian features are mammary glands and hairs. 6. Trap (gills and fins): these are fish features, absent in the platypus. 7. Trap (feathers and beak): feathers are bird features; the platypus has no feathers. 8. Trap (scales and claws): scales are reptilian, not the mammalian trait being asked. 9. Hence mammary glands and hairs is the correct mammalian feature. _Source: Balbharati (Maharashtra Board) Class 10 Science & Technology Part 2, Ch 1 "Heredity and Evolution", p.16_