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Darwin's theory of biological evolution helps us understand how simple life forms can give rise to complex lifeforms, but how did the first reproducing creatures come about? The origin of life needs its own explanation.

Join us as we explore the fascinating transition from early cells to multi-celled animals. This transition, as well as several other major evolutionary transitions, dramatically increased the complexity of lifeforms on our planet.

9:14 video Have you ever wondered how life first got started on Earth? So do scientists! Though the question has not yet been fully answered, a careful study of Chemical Evolution is beginning to shed light on this mystery. In this film you will learn what Chemical Evolution is, how it works, and how it is different from Biological Evolution.

7:00 video: This film is the first of a two part series on the evolution of new genetic information. Here we focus on Point Mutations - the simplest natural mechanisms known to increase the genetic information of a population. Our second film of the series will focus on duplication events - natural mutations that increase the total amount of genetic information of an individual. This film was produced under the guidance of molecular biologist Dr. Nicholas Casewell. http://www.lstmed.ac.uk/about/people/... Point mutations are small, natural edits in the DNA code of an individual. These edits can be passed from parent to child. Because they are mere edits, point mutations usually do not increase the total amount of information in an individual. As new information is gained, old information is lost. Point mutations do, however, increase the total amount of information within a population. In this film you will see several examples of beneficial point mutations which have enhanced a creatures abilities or even given rise to entirely new abilities. The first two examples were directly observed in bacteria by scientists in the lab. The third is a case found in domestic dogs, the last example was discovered in several species of wild animal.

The Miller-Urey experiment was the first attempt to scientifically explore ideas about the origin of life. Stanley Miller simulated conditions thought be common on the ancient Earth. The purpose was to test the idea that the complex molecules of life (in this case, amino acids) could have arisen on our young planet through simple, natural chemical reactions. The experiment was a success in that amino acids, the building blocks of life, were produced during the simulation. The finding was so significant that it kick started an entirely new field of study: Prebiotic Chemistry. Scientists now have reason to believe that the gases used in the Miller-Urey simulation were not actually the same as those of the ancient atmosphere. Because of this, many experiments have since been done, testing a wide variety of atmospheres and different environmental conditions. The results are overwhelming: the molecules of life can form under a wide variety of ancient Earth-like conditions. Many questions about the origin of life remain to be answered but these findings give strong support to the idea that the first living cells on Earth may have emerged from natural chemical reactions.

9 minute video

This animation was sponsored by the Center for Chemical Evolution, NSF, and NASA: http://centerforchemicalevolution.com/