1. Evolution
AND THE ORIGIN OF LIFE

2. Keywords
THINKS TO KNOW

3. Species
 Reproductively
isolated systems of
breeding
populations with
similar morphology.
 In simple terms;
organisms, that look
the same, that are
able to breed and
produce fertile
offspring.

4. Adaptation & Mutation
 Adaptation
 The evolutionary process whereby an organism becomes
better able to live in its habitat
 The change of an organism to be better suited to live in
its respective environment
 Mutation
 Changes in the DNA caused by radiation, viruses and
errors in DNA replication
 A change in the DNA that causes a significant change in
the organism’s phenotype or expressed traits

5. Common Decent, Ancestor & Descendant
 Common Decent
 A group of organisms that share the same ancestor
 Organisms that descended from the same organism
 Ancestor
 An earlier type
 A progenitor
 Descendant
 A later evolutionary type
 The offspring of an earlier organism

6. Variation and Natural Selection
 Variation
 The difference in characteristics typical of the group
 The difference between an organism’s traits and another
of the same species
 Natural Selection
 The process where favorable traits become more
common in each successive generation
 The process where nature selects the traits that best suit
the environment the particular organism lives in

7. Missing Link
 The
intermediate
organism
between
arthropod
apes and
humans

8. Genetics, DNA & Genes
 Genetics
 The study of the patterns of inheritance of specific traits
 DNA
 Deoxyribonucleic acid
 Contains the genetic material for cell growth, division
and function
 Genes
 Segments of DNA that are located on the chromosomes
 Controls the traits of an organism

9. RNA, Allele & Heredity
 RNA
 Ribonucleic acid
 Single stranded
 Allele
 One member of a pair of genes occupying a specific
part on the chromosome
 Can either be dominant of recessive
 Heredity
 The passing on of traits from parent to offspring

10. Central Dogma, Nucleotides & Proteins
 Central Dogma
 DNA is the carrier of genetic information in organisms.
 Nucleotides
 Structural unit of DNA/RND
 Made up of a 5-carbon sugar, a 3-phosphate group and
one of 5 nitrogen bases; namely
Adenine, Thymine, Guanine, Cytosine and Uracil
 Proteins
 Chains of amino acids

11. Chromosomes & Genetic Drift
 Chromosomes
 Organized structure of DNA and proteins
 Controls the expressed traits of an organism
 Genetic Drift
 A change in allele frequency
 Can be caused by a change in the environmental
conditions or a change in the reproductive selection of
the species

12. Phylogenetic Tree
 A branching
diagram
showing
inferred
evolutionary
relationship

13. Convergent and Divergent Evolution
 Convergent Evolution
 Different organisms develop similar traits to serve similar
functions
 Butterfly and Bird. They developed wings for the same
purpose.
 Divergent Evolution
 Similar organisms evolve to become more diverse until
they eventually become different species
 An population becomes separated and each separate
population adapts to a different niche and does so until
they become two different species

14. Scientists
WHO CONTRIBUTED TO THE THEORY

15. Carolus Linnaeus (1707-1778)
 Swedish Naturalist
 Nested Hierarchies
 Order of Nature
 Systema Naturae (1735)
 Father of Taxonomy
 Organized from species
to kingdom
 Two-part Name
 Binomial Nomenclature

16. Carolus Linnaeus (1707-1778)
Influenced by
 Plato
 Idealism and essentialism
 Aristotle
 Scala Naturae, The Great Chain of Being
 Organisms are arranged in increasing complexity
 Judeo - Christian
 Creationism
 Species are individually designed and are permanent

17. Thomas Malthus (1766-1834)
 English economist and clergyman
 “An Essay on the Principles of Populations”
 Food supply
 Arithmetic
 Population growth
 Geometric, logarithmic
 Food supply
limits
population
growth

18. Georges Cuvier (1769-1832)
 French Paleontologist
 Catastrophism
 A catastrophic event leads to extinctions of species that
are replaced by distant migrating species
 Earth’s age
 4000 - 6000
 Strongly opposed evolution
 The history of living organisms are recorded in
layers of as fossils

19. Jean Baptiste Lamarck
 French naturalist
 Early concepts of evolution
 Philosophie Zoologique (1809)
 Desire to change
 Use and disuse
 Passing on of acquired traits
 Species change over time into new species via
natural processes

20. Charles Lyell
 Scottish geologist
 Principles of Geology (1830)
 Uniformitarianism
 Geological processes are so uniform that their
rates and effects must balance out
Influenced by
 James Hutton (1726-1797)
 Gradualism

21. Gregor Mendel (1832-1884)
 Austrian Monk
 Father of genetics
 Proposed the laws of inheritance
 Used pea plants with different characteristics

22. Alfred Russel Wallace
 British Naturalist
 Studied in the Amazon
Forest and in the
Malaysian Isles
 “On the Tendency of
Varieties to Depart
from the Original
Type”

23. Charles Robert Darwin
 English Naturalist
 Studied in the
Galapagos Islands
 “On the Origin of
Species by means of
Natural Selection or
the Preservation of
Favored Races in the
Struggle for Life”

24. Evidences
PALEOEMBRYOANATOGEOCHEMISTRY

25. Paleontology
 Organisms evolved in a historical sequence
 The present id linked to the past
 Fossils form by chance and the quality varies
 Fossil reconstruction requires a thorough
knowledge of Anatomy
 Fossil
 Preserved remains or traces of organisms
 Dating rocks and fossils
 Geological or relative dating (strata)
 Numerical or radiometric dating (isotopes)

26. Comparative Anatomy
 Homologous Structures
 Features with different functions but similar structure due
to common ancestry
 Due to divergent evolution
 One species gives rise to many species that appear
different externally but are similar internally
 Analogous Structures
 Similar in appearance and function but of different origins
 Due to convergent evolution
 Different organisms develop similar structures to serve the
same purpose

27. Comparative Embryology
 Closely related organisms often have similar
stages or structure during early development
 Similarities in early development should mean
that similar genes are at work
 This is like a heritage acquired from their
common ancestor

28. Biochemistry
 Similarity of the DNA between individuals
determine their degree of relatedness
 Based on the
concept that similar
proteins are based
from the same DNA
or a common
genetic code
creates the same
protiens

29. Biogeography
 Observations about marsupial distribution show
that they are only found in America, Australia
and New Guinea
 Species were not distributed everywhere that
they could survive
 Islands have species endemic but are closely
related to species on the mainland

30. The 5 Evidences for Evolution
 Fossil Record
 Paleontology
 Similarities in Body Structure
 Comparative Anatomy
 Similarities in Early Development
 Comparative Embryology
 Similarities in Chemical Compounds
 Biochemistry
 Distribution of Species
 Biogeography

31. Genetics
A G T C U

32. Scientists
Rediscovered Mendel’s work
 Hugo de Vries
 Carl Correns
 Erich von Tshermak-Seysenegg
Discovered the structure of DNA
 James Watson
 Francis Crick

33. Nucleic Acids
 Polymers made up of monomers called
nucleotides
 There are 2 kinds
 DNA – uses A, T, G, C
 RNA – uses A, U ,G, C
 Stores and transmits information from one
generation to another
 Found in the nucleus of all cells

34. Proteins, Genes & Alleles
 Protein
 Polymers made up of monomers called amino acids
 Workhorses of living systems
 Gene
 A segment of DNA that codes for a particular trait
 The basic unit of heredity
 Allele
 A particular form of a gene

35. Genetic Code
 Set of rules by which information in DNA/RNA is
translated into amino acid sequences
 Red in
groups of
three
called
codons

36. Traits
There are two kinds of traits
 Single-gene trait
 Only controlled by a pair of genes
 There are only two varieties
 Example, Presence of the widow's peak
 Polygenic trait
 Controlled by numerous genes
 Has multiple varieties
 Example, Height.

37. Natural Selection as an Evolutionary Mechanism
 Overproduction
 Each species produce more offspring than will survive to
maturity
 Variation
 There is a variation of traits among the offspring
 Competition
 Organisms compete with one another for limited resources
 Survival to Reproduce
 Individuals that passes the most favorable combination of
characteristics are most likely to survive and reproduce

38. Genetic Variation
 Mutation
 Any change in the DNA sequence
 Due to an error in DNA replication
 Due to environmental factors such as radiation
 Gene Shuffling / Genetic Recombination
 Results from sexual reproduction
 Genetic Drift
 When an allele becomes more common in a population
by chance
 Implies that all characteristics of an organism don’t have to
contribute to the fitness of the organism to be favored

39. Genetic Variation
 Natural selection is not always necessary for
genetic change to occur
 Genetic variation is not controlled or directed
toward a cause. When a variation does occur,
natural selection goes to work
 If a species has enough genetic variation for it
to evolve quickly enough to keep up with the
environment, it will survive; if not, it will become
extinct

40. Ecology & Evolution
 No two species can occupy the same niche in
the same location for a long period of time
 This idea helps us understand how one species evolves
into many species
 Speciation by Reproductive Isolation
 Separation of populations stops interbreeding between
the two
 Separate populations adapt to different environments so
the gene pool becomes dissimilar
 The long separation eventually inhibits the interbreeding
between the two populations permanently