Evolution Of Flight In Birds Essay

In this essay we will analyse the evolution of flight in birds and how the ability of flight came about. However, to fully understand this topic we will have to evaluate certain specific aspects such as:

1. The common ancestor of all birds

2. Why and how birds evolved wings

3. Why certain birds did evolve wings however do not use them.

In the 19th century a nearly complete skeleton was discovered by Richard Owen in 1863 called the Archaeopteryx. It was recognised as a bird despite its clawed forelimbs and long bony tail which resembled a reptile (Owen, R. 1863).

Thomas Henry Huxley nearly immediately labelled he Archaeopteryx as a transitional fossil between birds and reptiles. He made many detailed assumptions between the Archaeopteryx and prehistoric reptiles and found that it was most similar to dinosaurs such as Hypsilophodon (Huxley, T. H. 1868) and Compsognathus (Huxley, T. H. 1870). However, even with the discovery of the Archaeopteryx with a complete set of reptilian teeth, many biologists notably Harry Seeley, argued that the similarities were just due to convergent evolution (Seeley, H. 1901).

Gerhard Heilmann of Denmark compared the Archaeopteryx and several other birds to a list of prehistoric reptiles just like Huxley. He came to the conclusion that theropod dinosaurs like

Does Dollo’s law not state evolution is irreversible? The answer is that birds such as penguins and ostriches evolved from birds which could fly due to the presence of wings, however due to their environments it was more favourable for them to develop other methods to acquire prey. For the penguins, they have heavy solid wings which allow them to dive deeper in the ocean to catch fish to feed on and as for the ostriches, they have developed large, long and powerful legs for running to catch prey. These adaptations are much more energy efficient than flying to gather food