What is Evolution?
Evolution is basically a change in allele frequency over time. This means that different types of traits change around over a long period of time. This shapes, and shifts organisms to what they are today. Allele frequency can change with a couple of different processes. First, mutation has to occur. Mutations are the only way new alleles are created, they can be harmful or helpful. Mutations have to be heritable meaning they have to affect gametes which are then pass on the mutation to offspring. The second process is genetic drift which is a random change in allele frequency. This can be seen in the founder effect (when a random sample of a population ends up in a new place) or a population bottleneck (which is when a random sample survives something). Another way allele frequency can change is through the migration of a group of individuals from one population to another. Lastly is natural selection (or "survival of the fittest) which is when the alleles best suited to the environment survive and reproduce more.
Natural Selection
Natural selection is a well known theory developed by Charles Darwin. It states that the alleles that help an organism reproduce more spread around and eventually the organism develops that trait. This occurs in various types including stabilizing selection which is when the environment supports the most average or "middle" type of a trait. Another type is directional selection which is when an environment supports the extreme of a trait. This can be seen in giraffes and how longer necks result in more food for the giraffe. Another type is disruptive selection which is when an environment supports both extremes. For example, if there were black, white and gray moths and only black and white trees, the black and white, or extremes, would prosper.
Evidence of Evolution
Evolution is shown in a few real world occurrences:
-Fossil record- different and varied fossils that have obviously changed over time due to relative dating.
-Geography- The same fossils are found in different continents like the East of South America and the West of Africa. This is due to common ancestors and similar environments. It also backs up the theory of Pangea which is basically that most of the continents were connected at a certain point in history and have spread apart.
-Comparative anatomy- Different organisms have similar bone structures or other traits but have evolved differently and branched our from this origin organism. This can be shown is homologous structures, vestigial organs, divergent evolution, convergent evolution, embryology, and molecular biology like similar DNA.
-Fossil record- different and varied fossils that have obviously changed over time due to relative dating.
-Geography- The same fossils are found in different continents like the East of South America and the West of Africa. This is due to common ancestors and similar environments. It also backs up the theory of Pangea which is basically that most of the continents were connected at a certain point in history and have spread apart.
-Comparative anatomy- Different organisms have similar bone structures or other traits but have evolved differently and branched our from this origin organism. This can be shown is homologous structures, vestigial organs, divergent evolution, convergent evolution, embryology, and molecular biology like similar DNA.
Special Adaptations
-The Goblin Shark has a mouth designed to suck any smaller animals inside its mouth by projecting its jaw at prey.
-The Goblin Shark can go without food for extremely long amounts of time.
-The Goblin Shark can swim incredibly stealthily without shifting the flow of water, making it extremely hard for prey to detect.
Evidence of early forms of the Goblin Shark can be seen in multiple other sharks. The Goblin Shark has, supposedly, been somewhat the same since prehistoric times due to a lack of environmental change.
-The Goblin Shark can go without food for extremely long amounts of time.
-The Goblin Shark can swim incredibly stealthily without shifting the flow of water, making it extremely hard for prey to detect.
Evidence of early forms of the Goblin Shark can be seen in multiple other sharks. The Goblin Shark has, supposedly, been somewhat the same since prehistoric times due to a lack of environmental change.