The concept of a flightless bird is a weird situation to end up in. Nonetheless, there are many species of flightless birds that exist. In fact, there about 40 species of flightless birds so far. The most common one is probably the ostrich or emu, both of which are considerably larger than the average bird. They exist in the wild and in farms for eggs, feathers, and even meat.
But first, let’s get one thing straight, do penguins have knees? The answer is yes!
The emu is renowned for its military prowess as it defeated the Australians in the Great Emu War, which is a genuine event in 1932 when the Australian government wanted to cull the emu population and failed. One of the most famous extinct flightless bird is the dodo, which was on the Galapagos Island and made famous by Charles Darwin. It went extinct because it was on an island without any predators and when it encountered humans, it failed to protect itself.
Among most birds and animals, the penguin stands as one of the more popular creatures. They were in many different movies, television shows, and other areas of the media to ingrain themselves in the human mind. But, what is a penguin and how does compare to other birds.
Penguins are represented by the taxonomic order Sphenisciformes, which are aquatic and flightless birds. Researchers estimate that there are 17 to 20 species of penguin and majority of them live in the southern hemisphere. The only exception to that is a species of penguin that lives north of the equator at the Galapagos Islands.
Even though we generally associate penguins with the icy cold of Antarctica, only a few species actually live there as many do not thrive in such cold temperatures. Some are found in temperate or even tropical environments. As humans began exploring penguin habitats, they found that penguins had little to no fear of humans. This is probably because they did not have any predators on land and did not associate humans with anything underneath the sea.
Penguins are also very social and live in large clusters of penguins throughout their habitats. These social environments allow them to become both safe in numbers and help to deal with the cold as they can roost together. The oldest penguin fossil species comes from the early Paleocene epoch, about 63 million years ago. The species, Waimanu manneringi, was a flightless bird with short wings that was becoming adapted to an aquatic lifestyle. This indicates the length of time that penguins have remained flightless and aquatic. Over time, these two characteristics only became stronger and enhanced as the aquatic lifestyle of the penguin allowed it to be highly successful at surviving and thriving.
The General Anatomy of Penguins
Penguins have become highly adapted to the aquatic lifestyle after all those millions of years of evolution from ancestors like Waimanu manneringi. Like other birds, penguins do have wings. Unlike other birds, those wings have basically become flippers used for swimming and diving. They also have a plumage of feathers, but their feathers are very smooth and thick so that they can be insulated from the cold. Within the plumage of feathers, there are layers of air that helps to also insulate the penguins as well as keep them buoyant when they enter the water.
One of the most striking features of penguins is their black and white coloring. This is a camouflage coloring because of the black, when seen above the water, looks like the darkness of the ocean. Unlike many other birds, penguins have only an average sense of hearing because it is not needed nor efficient underwater. They have developed excellent eyes for underwater. The white, when seen from below the water, looks like the surface of the water that has been bathed with light. This protects them from any predators that might want to snack on them. While on land, penguins use their wings and tails, which are short, to balance themselves.
When you look at a penguin, you see a round and relatively smaller creature with tiny feet at the bottom. You do not really see any legs or bone structures besides their webbed feet, which they use to wobble with. Penguins do in fact have knees, femurs, and many other bone structures. They are all hidden under the thick layer of their body. The bones of penguins, unlike other birds, are very dense and thick because they need to be able to dive quickly and stiffen their wings so that they can be highly efficient in the water. Having thin bones or bones with air pockets would only slow them down and prevent them from diving deep into the water.
Size Variance Among Penguins
One of the biggest differences amongst penguins is their size. The largest penguin species is the Emperor Penguin, which can become as tall as 48 inches and weigh up to 99lbs. The smallest penguin is the little penguin, which is usually about 16 inches tall and weighs around 2.2 lb. The size difference is staggering but serves the purposes of each species.
The larger size of Emperor Penguins allows them to dive deeper into the sea. They also live in Antarctica. Emperor penguins can dive as deep as 535m while little penguins can reach depths of 20m, a reflection of their size difference. Emperor penguins have denser bones than most penguins, pulling them down deeper as they dive, and they have developed means of surviving in low oxygen environments. They have also developed ways to slow down their metabolism and not burn a lot of energy. The little penguins do not have deep advance adaptations because it does not suit its environment, which is in areas like New Zealand, and its food source, which is easily acquired compared to the Emperor penguin.
While penguins are birds, they are birds of the sea rather than the air. Their swimming looks like they are gliding and flying through the water as elegant and efficient as any bird flies through the air. Their bodies have evolved to provide this efficiency and as they continue to thrive, they will probably evolve to become better at it. It is up to us to help them thrive by understanding their habitats and behaviors and how those are affected by climate change, environmental disasters, and other problems attributed to humans.