Question 2: the correct answer is Bat. Got it right? Score 1 point.
Question 3 of 10
Which of these animals is a mammal?
Why, in question 2: Which is the only mammal able to fly by flapping its wings?
The answer is the bat. The flying squirrel only glides, using a membrane between its legs, and cannot gain height. The hummingbird flies very well, but it is a bird, not a mammal, and the penguin is a bird that cannot fly.
Gliding is not flying
Several animals can glide: flying squirrels, some lizards, frogs, and even snakes that launch themselves from trees and control their descent. But real flight, climbing and staying aloft by flapping the wings, is something only insects, birds and bats do today.
The bat's wing is a skin membrane stretched between very long fingers, the arms and the legs. It changes shape with every beat, which gives the bat remarkable agility to make sharp turns in the dark.
Bats are the second largest group of mammals by number of species, behind only the rodents. They range from species weighing a few grams to large fruit-eating bats with wingspans over 1.5 metres from tip to tip.
Many bats spend the day hanging upside down. Tendons in their feet lock their claws in place without using energy, so they can rest this way for hours. To fly, they simply release their grip and open their wings as they drop.
