Introduction:
Penguins are flightless and aquatic birds, mainly the resident of the Southern Hemisphere. Now, the question is Why can’t penguins fly? There are a total of 17 species of penguins. Most of the penguin species can be found in the Antarctic region and the islands surrounding it. Only the Galapagos Penguins live closest to the equator on the Galapagos Islands. As time passed, penguins went through the cycle of evolution and lost their ability to fly. Penguins gave up their wings for flippers which help penguins to swim in the water. The evolution of penguins is a very hot topic among researchers. Many research papers and articles have been published on the Evolution of Penguins.
Penguins Evolution:
Based on the discovery of old fossils and research, penguin’s evolution can be divided into 3 sections.
- Basal Fossils
- Palaeeudyptinae
- Modern Penguins
Basal Fossils
According to researchers, the oldest known fossil of penguin species is of Waimanu Manneringi or Waimanu penguins. Waimanu penguins lived in New Zealand in the Paleocene period around 62 million years ago. This species of penguins was not as adaptable to underwater swimming as modern penguins but they did have the ability to swim and had lost their ability to fly. They had short wings that were adapting to swim underwater and used their feet to swim on the surface of the water. Other than Waimanu penguin fossil, Perudyptes fossil was found from Peru and the scientific analysis of Perudyptes fossil shows that this species of penguin lived around 42 million years ago.
A fossil was found from Argentina whose name is not yet determined by scientists. An in-depth analysis of this fossil showed that it is from Bartonion Period around 39-38 million years ago. The discovery of this unnamed penguin fossil shows that primitive penguins had already reached some parts of South America and they were in the process of expanding to Atlantic waters.
Palaeeudyptines:
Palaeeudyptines is basically a group of those penguin species that had been gone extinct many years ago. The extinct species of penguins are placed in this group, without any regard to size. So, this group includes penguins that are small and larges in size.
According to researchers, there were some species of giant penguins that lived during the Late Eocene and the Early Oligocene around 40 to 30 million years ago. Two species of giant species were found in the area of New Zealand. Nordenskjoeld’s giant penguin were the tallest in the penguin species and they had a height around 5.9 feet. The New Zealand Giant Penguins were the heaviest among the penguins. They weighed around 80 kilograms or more. The New Zealand Giant Penguins were also found in the Antarctic region.
According to scientist, there were around 10 species of penguins that coexisted in the Antarctic region around 35 million years ago, ranging from medium to huge.
The most well described giant penguin is Icadyptes, which was around 5 feet tall and lived in the northern area, expanding as far as to Peru around 36 million years ago.
The gigantic penguins disappeared around the end of Paleogene period, around 25 million years ago. The cause of their disappearance and extinction was the appearance of other primitive fish eating animals who competed with gigantic penguins for food and were more adaptable to underwater conditions as compared to gigantic penguins.
Modern Penguins:
If we look at the modern penguin species of penguins, we can see that the most nearly related penguin specie to Basal Fossils is Aptenodytes. This specie of penguin is the resident of Antarctic coasts.
Pygoscelis is a group of penguins which contains 3 species of penguins. These group of penguins mainly resides in the Antarctic coast region and extends to northwards. In structure and appearance, they still resemble to their common ancestor of the Spheniscinae. The modern diversity among these penguins occurred around 20 to 15 million years ago.
The group Spheniscus and Eudyptula is made of those species that live in the Sub-Antarctic region which consist of North American countries like Argentina, Ecuador, Peru and Chile. Their divergence from their ancestor occurred around 4 to 2 million years ago.
Did Penguins Ever Fly?
The fossil of Waimanu penguin is the oldest fossil and known ancestor of the modern day penguins. Waimanu penguins already lost their ability to fly. That’s the reason scientists and researchers say that modern day penguins evolved from the flightless bird. The ancestry behind the Waimanu penguin is unknown so nothing can be said about when did the penguins lost their ability to fly and how did this diversity occurred.
Why Did Penguins Stop Flying?
Recent research says that birds can either have their ability to fly or they can have the ability to swim. It is not for possible for birds to have both. According to modern research, there are 4 main reason for the loss of the penguins’ ability to fly.
- Swimming
- Energy Efficiency
- Food
- Size
Swimming:
Penguins’ ability to swim underwater is better than most flightless birds that swim under water. That is because unlike the light bones in the wings of other birds, the bones present in penguin’s flippers are heavy and they give penguins the ability to swim and dive deep in water. Penguins use these flippers to move underwater and propel themselves instead of using their feet to move underwater. The solid bones present in penguin’s flipper like wings, give them the ability to not only float but also to dive. Emperor penguin has the ability to dive 1,500 feet underwater.
Energy Efficiency:
The question that why did penguins lost their ability to fly bugged scientist for a very long time. To get the answer of this intriguing question, a team led by biologist Kyle Elliott at the University of Manitoba in Winnipeg, Canada, examined many diving seabirds that have the ability to fly like the thick-billed murre.also known as Brünnich’s guillemot. Thick-billed murre are closely related to penguins but they also have the ability to fly. Researchers tagged murre and observed it actions for a very long time. The team came to this conclusion that murre needs a lot energy when the have to beat their wings to come out of water and fly.
Due to this reason of use of excessive energy, at some point of time, penguins lost their ability to fly, mainly focusing on swimming and diving. It was more efficient for them to swim as compared to flying because they had to find their food underwater.
Food:
Another main reason of penguins’ loss of flight is food. Penguins spend almost 75% of their lives in water. Penguins come to shores and land only to mate and to molt. With the appearance of other underwater animal, penguins had competition with other. They sacrifice their ability to fly so they can dive deep underwater and because they are excellent divers, as compared to other seabirds, penguins can go to more depth up to 1,500 feet. Penguins usually eat fish, squids and krill depending on the specie and penguins only eat when they are in water. Penguins fast when they are on land.
Size:
Size is also a major reason why penguins cannot fly. As compared to other birds, penguins have huge and heavy bodies. These bodies help penguins be safe against the cold climate of Antarctic region but it’s also the reason why they lost their ability to fly. Because of these heavy bodies, penguins can’t take off from ground although this helps them a lot when they dive underwater in search of food or when they have to migrate from one place to another.
Can Some Penguins Fly?
Penguins are flightless birds and there are no species of penguins that can fly. Penguins spend 75% of their lives in water, so according to some scientist, penguins can fly but instead of fly in the air, they “fly” in water which is 900 time denser than air.
There is a documentary film trailer by BBC Nature called “Flying penguins” or “Miracles of Evolution” which is an April’s Fool hoax. It show some Adélie penguins that are flying.
Do Penguins Have Wings or Flippers?
Flippers of penguins are basically their wings but with evolution, the wings turned into flippers. Not all birds have flippers but all penguins do. Unlike ducks, geese and other birds who use their feet to swim, penguins use their flippers to propel themselves underwater. Penguins use their flippers which are attached to their shoulders. Their wrist and elbow are fused together which give penguins more power.
As compared to other birds, penguins cannot move their flipper straight up and reach up from their head, this movement is needed for birds to fly but it’s a hurdle when it comes to swimming underwater. Penguins do have feather on their flippers but unlike other flying birds, their feathers are small, short and well packed. This arrangement off feathers allow penguin to minimize the underwater drag and it also provide them with safety against the cold weather that they face in the Antarctic region and cold waters.
How Penguins Lost Their Ability to Fly?
The simplest answer to the question, “How penguins lost their ability to fly?” is one word, Evolution. Modern day penguins are the descendants of Waimanu penguin which existed around 62 million years ago. Waimanu penguins were already flightless birds who were adjusting to their ability to swim underwater. The Ancestry of Waimanu penguin is unknown and scientist are not sure about during which point in time, penguins lost their ability to fly and gain the ability to swim underwater.
The reason that why did the penguins decided to give up their ability to fly bugged scientists for a very long time. The reason is that emperor penguin takes a journey of 60 km for many day when the same thing could be done in few hours if the penguins had the ability to fly. And also, even though penguins are excellent swimmers, they’re prey for other lifeform that can also swim underwater like seals. So, why penguins lost their ability to fly. The reason is following.
- Access to food
- Energy
- Diving
Access to Food:
Penguins spend around 75% of their lives underwater and only when they are in water, they hunt and eat their food. When they come to shores, they fast and don’t eat anything. Penguins mostly eat squid, krill and fish depending on the kind. The reason why did they lose their ability to fly is to gain the ability to dive deep underwater in search of food. Because of the appearance of other birds that can swim and predators that can hunt underwater, penguins needed the ability to dive deep underwater. The emperor penguin can dive up to 1,500 feet deep underwater. During the summer, an active, medium-sized penguin will eat about 2 pounds of food each day, but in the winter they’ll eat just a third of that.
Energy:
The recent study show that those seabirds who can fly and swim as well, like thick-billed murre, they need to spend 31 times more energy to beat their feathers when they come to the surface of water to breathe as compared to when they have to beat their feather to fly in the air.
Due to this reason of use of excessive energy, at some point of time, penguins decided to lose their ability to fly, mainly focusing on swimming and diving. It was more efficient for them to swim as compared to flying because they had to find their food underwater.
Diving:
Penguins are excellent divers, with species like emperor penguin which have the ability to dive up to 1,500 feet deep underwater. Penguins accomplish this feat because of their flipper like wings which give them the ability to propel themselves in the depths of cold water unlike other seabirds like ducks who need their feet to move underwater. The feather on the flippers are smaller and dense which provide them protection against the cold water and harsh climate of Antarctic. The shape of the flippers reduce the drag that they have to face when they are moving underwater.