Bats are true mammals because they give birth to live young, produce milk to feed their young ones. They are warm-blooded because they can self-regulate their body temperature. Bats use their wings to fly and also to catch their prey, mostly flying insects. Bats are more closely related to small, tropical primates than to rodents irrespective of their size.

Whales are mammals even though they are aquatic, it might look like a fish but hierarchically it is an aquatic mammal. They spend all their life in the sea but still are similar to us. Whales give birth and feed on milk to offspring whereas the fishes lay eggs. Even Whales are warm-blooded animals. It belongs to an order called Cetacea which also includes porpoises and dolphins. They have a streamlined body and have flukes at the tail.

Bats and whales are considered mammals because they share key characteristics that define mammals:

• Warm-blooded: Both bat and whale can regulate their body temperature internally, maintaining a constant temperature regardless of their surroundings.
• Live Birth: Most mammals, including bat and whale give birth to young one.
• Milk Production: Female bat and whale produce milk to feed their young ones.
• Lungs for Breathing: Both breathe air using lungs. Whales despite living in water, surface to breathe through a blowhole, while bat breathe air like other land mammals.