Sumary

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Where does species come from?

In 1858 the naturist Charles Darwin and Alfred Russel Wallace proposed the concept of natural selection, Darwin gathered in evidence for this idea an publish his book in 1859 On the Origin of Species by Means of Natural Selection.

They observed that organisms must struggle to obtain food & sources to survive an reproduce, they get to the conclucion that this survival traits would be prevalent in future generations from a process called natural selection acording to this life has evolved into 6 major groups of species.

This view sees the development of life as a ever-branching tree of species called the Tree of Life, this teory explains how life has change throught the pass of time & why life is pretty diverse now a days.

The fossils as Evidence

Fossils are mineralized & petrified replications of skeletons, bones, theeth, shells, leaves & sedes or impressions of such ítems found in rocks.

Fossils provide fisical evidence of ancient organisms & reveal what there internal structure looks like; The fossils found so far probably represent only 1% of all species that have ever lived.

Biological evolution by natural selection involves changes in a populations genetic makeup through successive generations; Genetic viability in a population occurs through mutation, most of this mutations result from a random changes that occurs in DNA, they occur in any cell but those only take place in reproductive cells that are pass through the offsprings.

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