Life on eath is incredibly varied
There is an enormous number of species on this eart scientis are not sure how many but estimates vary from 2 million - 100 milion.
There are also loads of species that have become extinct so since life began a huge number of things have existed on this planet.
The very first living things were simple. Life then evolved to become complex and varied. All living things that exist now and have ever existed evolved from those simple early life forms.
There is good evidence for evolution.
Fossil records and DNA provide good evidence for evolution.
There is evidence for evolution in the fossil record which shows species getting more and more complex as time goes on.
DNA controls the characteristics of living things. It also changes and mutates over time