The Evolution of Penguins

http://bioexpedition.com/penguin-evolution/

Summary

          Penguins, as we all know, are flightless birds that now swim in bodies of water. Penguins once had wing-like structures rather than the flipper-like structures that they have today. It is thought that this change occurred about sixty-five million years ago and that penguins were once able to fly. One theory as to how penguins evolved is that some birds that could fly came to Antarctica possibly looking for food. They then could have adapted to their new environment (founder effect). Penguins may not have been able to get all of their main necessities on land only and therefore went to the ocean to survive. Being in the ocean to obtain food forced them to adapt, and over millions of years, their weak wings became strong, thick-boned flippers. Since wings must have light bones to fly and reduce extra weight, these thick-boned birds could not fly. Some fossil remains show that penguins are at least sixty million years old.

Relevance to Class

          Recently, we learned about evolution. This article talks about the evolution of penguins and how they evolved to have flipper-like structures. Also, in class we defined the founder effect to be a type of genetic drift when a few members of a population go to a different location, often one with different environmental conditions. One of the theories of penguin evolution involves the founder effect, as well as adaptation to a new habitat. Also, like some of the finches at the Galapagos islands, there is directional selection. Those birds with more of a flipper-like structure would survive, and those without these structures had less of a chance of surviving due to lack of resources on land.

URL: http://bioexpedition.com/penguin-evolution/
Author of Article: N/A
Date of Publication: November 13, 2012

By Rachel Levine