Adaptations | Answers

1. How do penguins feathers work to keep them warm?

Adélie Penguins have about 100 feathers per square inch, which is a density that is far higher than in other birds. Their feathers are short, cup-shaped and overlap closely to make a waterproof covering for the body. The base of the feather has downy tufts that trap the warm air near the penguin’s skin. Adélie Penguins also have a layer of down growing beneath the contour feathers, as well as a thick layer of fat under their skin that further helps to insolate their bodies from the cold.

2. What happens if the penguins lose or damage their feathers?

Penguins preen to keep their feathers in good condition, but the feathers do become bleached and more brittle from the 24 h of constant sunlight over 4-5 months in summer. Every year, after the nesting season, Adélie Penguins molt, which means they lose their feather and grow new ones. The new feather grows under the old one and pushes it out. While the penguins molt they do not enter the water or feed as they are not insulated against the cold water until the molting process is complete. It takes 15-25 days to complete the molting process during which time the penguin will stay on the ice floe. Only a few Adélie Penguins choose to molt on land.

3. How do Adélie Penguins find their nesting colony when it is time to breed?

Adélie Penguins use celestial cues (angle of sunlight, and probably star patterns) to navigate over long distances. Within sight of their colony or seeing the mountains above them as cues, they use sight. Once at the colony, which can stretch over many acres or hectares, they use sight to find their nest.

4. The penguins at the zoo never fold their wings like the other birds, why is that?

Penguin wings have evolved into the form of paddles. The tendons holding the bones together in their wings are very short and tight in order to withstand the pressure of water as they swim.

5. We have been learning about adaptive coloration in animals and it seems black would not be a good color for a penguin. Isn’t it easy for their predators to see them against the ice?

Adélie penguins have no land predators so the color black is not a hindrance for them. In fact, the dark plumage actually helps keep them warm by absorbing the energy from the sun. When they are swimming their white underside makes it hard for their ocean-going predators to see them if they are below the penguin looking up. The same is true for the penguins’ prey, if they are below.

6. Adélie Penguins don’t have feathers on their feet. Don’t they loose a lot of heat from their legs and feet when it is exposed to the ice, water and cold air?

A process called counter-current heat exchange transfers the heat from blood vessels going to the feet warming the blood as it comes from the feet. This way the blood is already cold when it gets to the feet and has less heat to lose to the environment. Most of the heat is retained by the body. A similar process traps the heat in the penguin’s expelled breath through their noses, helping to conserve that precious body heat.

7. Do Adélie Penguins have any predators?

Yes, Leopard Seals kill and eat many penguins. They catch them mainly by stealth and surprise, as the penguins can out-swim the seals in open water. An individual seal might eat 4-5 penguins each day.
Aside from Leopard Seals, as chicks Adélie Penguins face Skuas and Giant Petrels as significant predators. The skua is a gull-relative and the Giant Petrel is a bird related to albatrosses. Both are very aggressive species of flying seabird that can pull young penguins out of their crèche. The can do this until the penguins are about 25 days old. The penguin chicks usually have adults nearby to guard them against these predators, but in years when food is scarce, few are present as they are away looking for food.

8. Do penguins blink their eyes? (Ryan, CT)

Yes, in two ways. They’ve got eye lids just like you, and they blink them. They also have a membrane that moves across their eye from one corner to the other and they blink this one, too. All birds have this second one: it’s called the “nictitating membrane.” Keeps their eyes clear.

9. How are fused flippers different from flippers?(Peter, WI)

Some of the bones in penguin wings are fused, and some of the tendons are short and strong, which means they can not fold their wings like other birds. It would be like you not being able to bend your elbow backward. This makes them stronger in the swimming motion like the fin of a dolphin.

10.The scientists said that the Emperor penguins held their breath for 20 minutes. Is a penguin's body adapted to hold its breath and open its beak to catch food at the same time? (Mrs W. CT)

Yes they can hold their breath and open their mouths and swallow. You can too, and you do this all the time.

11. Do penguins have knees? (Brittan, TX)

Yes their leg bones form a knee. See the picture on the “adaptation’ page of the website, under “feet”