Dayton Chow Keegan Friesen Kyle Flavin Nick Kruiper Ancestors Hesperornis (Lived around 78-84 million years ago in the Cretaceous Period) The scientific name for birds in general is Aves. The scientific name for the modern day birds is Ornithothoraces. Theropods (carnivorous creatures such as: velociraptor or Tyrannosaurs rex) are widely considered by scientists as the true ancestors of birds. Archaeopteryx (Lived around 150 million years ago in the Jurassic period) Ancestors (Continued) Liaoningornis (Lived around 125 million years ago in the Early Cretaceous period) Larry Bird (Still alive today but has lost his ability to fly) Musculoskeletal Evolution Birds originally evolved from raptors and walked on all fours. overtime their body's became slimmer and claws became smaller eventually they started walking on only 2 legs and losing strength in the arms and gaining it in there legs, this made them faster and more agile. much later there arms started growing in an upwards fashion and forming a web like skin flap underneath the arm, the wings were still not big enough for full flight but biologists resulted that they used the smaller wing to slightly glide over the ground for increased speed. overtime birds evolved with larger wings with feathers attached and even slimmer body's giving them the ability for full flight as well as ground movement. Agents of Evolution Genetic drift took affect on birds when resources were depleted and predators became stronger in the area. the birds would simply fly to the new environment where they would thrive. the new environment would work with and against there current state, depending on how easy it was to obtain food, the predators they faced and the surrounding agriculture. certain genes would be selected to over a long period of time create the most fit animal to survive the new environment. The same cycle would occur when new resources or other predators would needed or evolve. The environment is a big reason why birds begin to mutate and change. If a natural disaster occurs; birds, like any animal have to adapt. For example, birds could survive a volcano explosion if they can fly over the ash or stay in the air for a long time until they can find a new area. If there is a high flood, birds that can fly higher would have a better chance of surviving and finding an area to rest, thus making them more likely to survive and send their genes to offspring. If a large storm were to arise it might force a population of birds to flee their habitats in order to survive. They would be forced to adapt. For example if they migrated to an are with a colder climate and the only source of food was worms in the ground their body's would have to evolve to suit their environment. By growing a longer beak to eat worms underground and grow longer thicker feathers to stay warm in the cold climate. Environmental/Cultural Changes (continued) There is a vast number of bird species and sub-species throughout the world, some have similar characteristics, (appearance, vocals), while other species are completely different. This is due to the development of birds in different regions. Naturally, organisms develop and attain new traits very slowly over generations. These traits help them survive better in their environment, giving them an edge over other competition, therefore improving their chance of survival. At one point in time, when birds first made their appearance on our planet, they all looked very similar. But as they began to spread and separate, moving to different regions, changes start taking effect. An easy way to explain how "birds change with the region" would be to refer to the observations of Charles Darwin. The 19th centaury British scientist, Charles Darwin, observed while spending time on the Galapagos Islands, that there were many different sub-species of the Galapagos Finch. They all had similar looks, but the beak of finches on one island, differentiated from the other. The reason for this was overtime a population of finches moved to the Galapagos, and as they travelled to different islands there was different food sources. Each species gained different traits to help them survive in their conditions. A finch who eats insects has a shorter beak, while one who drinks from a cactus has a longer beak. This motion of evolution is known as Darwin's theory of Natural Selection. Natural Selection doesn't just affect one species of birds. It affects them all. Compare a penguin to a owl. Then compare a eagle with an ostrich. What are the differences? What are the similarities? The similarities of all birds, no matter where they are in the world, are the traits that all birds have, and are similar even if they provide different functions. Examples would be the wings of hawk, versus the wings of a hummingbird. They are similar, but slightly different, though internally, the structure of the wings are similar. Feathers, and beaks are also used to classify birds, and they also are traits that develop differently overtime. http://blog.hmns.org/2010/05/flat-footed-reptiles-to-high-stepping-chickens