Charles Darwin (1809 -
1882)
Document
Download and print Tree of Life poster
(pdf file, 2.6Mb)
Open
Evolution timeline
Darwin's theory of evolution explains how life on Earth has changed over geological
time. Scientists believe this is the reason why all living things on Earth exist today. The
theory is supported by evidence from fossils, and by the rapid changes that can be seen
to occur in microorganisms such as antibiotic-resistant bacteria. Many species have
become extinct in the past and the extinction of species continues to happen.
The basic idea behind the theory of evolution is that different species have developed over time
from simple life forms. These simple life forms first developed more than three billion years ago (as
the Earth is believed to be about 4.5 billion years old).
This timeline shows key events in the evolution of life forms on Earth, from the first bacteria to the
human species.
You can see a more detailed history of life timeline on BBC Nature.
Charles Darwin is famous for his theory of evolution, but he was not
the only person to develop such a theory.
Darwin’s theory
Charles Darwin was an English naturalist. He studied variation in plants and
animals during a five-year voyage around the world in the 19th century. He
explained his ideas about evolution in a book called On the Origin of Species,
which was published in 1859.
Darwin's theory caused controversy among his contemporaries and his ideas
were only gradually accepted, although some people still do not believe them
today. The reasons for skepticism include:
Darwin’s theory conflicted with religious views that God had made all the animals and
plants on Earth
Darwin did not have enough evidence at the time to convince many scientists
it took 50 years after Darwin’s theory was published to discover how inheritance and variation
worked.
Lamarck’s theory
Jean-Baptiste Lamarck was a French scientist who developed an alternative theory of evolution at the
beginning of the 19th century. His theory involved two ideas:
