• Molecular Evolution

Evolution can also be observed in molecules. While comparative anatomy has shown how limbs have evolved from fins, present day technology allows scientists to take a look at the genetic material itself, DNA.

All living organisms convert food into energy in the form of ATP. Whether that organism is a flower that absorbs nutrients and water from the soil and light from the sun, a lion devouring a wildebeest, or a human being enjoying an exquisite meal in a fine restaurant. The food gets processed by passing through the digestive tract and the nutrients are transported through the bloodstream to all the cells in the body, where they are converted into the molecule ATP in the mitochondria. This ATP is then used to provide energy for the cellular processes. It provides the fuel to produce proteins and the production of these proteins is guided by the genes in the strains of DNA.

• Mutation speed

Biochemists have analyzed proteins in an attempt to learn more about how the genetic material is expressed in different organisms. When organisms produce similar proteins, they must possess similar genes. The more recent species are evolved from a common ancestor, the more proteins and genes they have in common. This is called homology. Vice versa, the less homologous proteins and genes species have in common, the longer it’s been since they went their separate ways.

Proteins associated with DNA molecules, are called histones. The amino acid sequence of one of these histones is surprisingly similar in an incredible amount of species. This fact supports the theory that a single organism was the ancestor of all known organisms on earth.

One of these long conserved sequences produces a protein called cytochrome-c, which is a part of the electron transport chain that takes places in the mitochondria. A mutation can lead to another protein being produced. Even though mutations sound like dreadful events, they happen quite regularly. They even occur in such a regular manner, that there are known mutation speeds for certain genes. Mutations make it for organisms to slowly change and yes, sometimes mutations can have profound effects, but usually they occur unnoticeably.

Scientists can use the mutation speeds of genes to determine how long it’s been since two species diverged. And in support of Darwin’s theory, it appears that the amount of time calculated through theses mutation speeds is very similar to the data paleontologists have discovered through the dating of fossils.