Charles Darwin published his theory of evolution by natural selection in 1859. He proposed that populations evolve over many generations through a process where individuals with traits beneficial for survival are more likely to reproduce and pass on those traits, while less favorable traits are gradually lost. This theory laid the foundation for modern biology and ecology. It explains observations such as related species having similar embryos and bone structures. While controversial initially, evolution is now widely accepted in science and influences fields like medicine, agriculture, and ecology.

1. Darwin and Consequences
by Alex Iliescu

2. Charles Darwin (1809-
1882)
 British naturalist famous for his evolutionary
theory which is the foundation for modern
biological and ecological science
 Published his theory in Origins of Species in
1859
 Populations evolve gradually over many
generations through the process of Natural
Selection

3. Natural Selection
 Natural process in which individuals with most
beneficial traits are able to successfully
reproduce passing on these traits to their
offspring, and individuals with least
favourable traits cannot successfully
reproduce leading to loss of such traits over
time
 Based on competitive advantage (survival of the
fittest)
 Acts slowly and gradually
 Central mechanism for evolution

4. Recapitulation (Origins of
Species)
 Evolution is a slow and gradual natural
process acting over many generations
 Certain physical and behavioural traits are
gradually improved to suit certain environments
 Variability among these traits
 Struggle for survival
 All changes are slow and gradual

5. Recapitulation (Origins of
Species)
 Darwin is aware that the fossil record
provides the greatest challenge for
acceptance of his theory
 Not every collection of fossil remains provides
evidence for gradual modification of organisms
 Only way he can counter objections to his
theory is by assuming that the geological
record is way more flawed than most
geologists think

6. Recapitulation (Origins of
Species)
 Observations from the Galapagos Islands and
other islands in the Americas and Africa
 Animals from these islands resemble striking
similarities to animals on the nearby mainland
 These facts can’t be explained by Creationism

7. Recapitulation (Origins of
Species)
 Common similarities of limb bones and
striking similarities among embryos of
different species yet radically different to their
adult forms explain the gradual and slow
modifications of evolution

8. Recapitulation (Origins of
Species)
 All organisms are related in their chemical
composition and cellular structure and they all
undergo growth and reproduction
 All organisms on earth are derived from one
common ancestor
 Striking similarities among embryos and bone
structures

9. Recapitulation (Origins of
Species)
 Because we fail to perceive the slight
variations accumulated over geologic time
periods, we find it extremely difficult to accept
the theory of descent with modification

10. Influence on modern science
 Theory of evolution has been carefully tested
many times and is widely accepted in the
scientific community
 Ongoing research in the field of biological
evolution is leading to many new discoveries
that are helping us better understand
evolutionary mechanisms
 More evidence supporting this theory comes
from experiments in molecular biology

11. Influence on modern science
 Darwin’s famous theory also laid the
foundation for modern ecology
 Natural Selection in ecological terms describes
how organisms in a given ecosystem compete for
resources
 Ecosystems are constantly evolving as organisms
are born, die, immigrate to an area and emigrate
from an area
 Thorough understanding of population dynamics
requires a thorough understanding of evolutionary
theory

12. Influence on modern science
 Evolutionary theory has major positive
implications in the medical field
 Since both victims and disease-causing
organisms evolve, an understanding of
evolutionary theory is critical in treating or
curing diseases

13. Questions
 Are there any negative implications of
applying evolutionary theory to the field of
medicine?
 How might an understanding of biological
evolution be applied to making our
agricultural system of food production more
sustainable?

14. Sources
 http://www.bbc.co.uk/history/historic_figures/darwin_charles.sht
ml
 https://secure.wikimedia.org/wikipedia/en/wiki/On_the_Origin_of
_Species
 http://www.scientificamerican.com/article.cfm?id=dynamic-
darwinism
 http://evolution.berkeley.edu/evolibrary/article/medicine_01