Evolution

1
Evolution

• Evolutionary Thought
• Theory Takes Form
• Evidence from Fossils, Biogeography, Comparative
  Morphology, Comparative Biochemistry

2
Evolution

• Change in genetic makeup over time

3
Humans

• Belong to the order Primates
• Hominids human-like species that existed up to
  several million years ago
• General trends seen in hominids ? humans
• More reliance on vision
• Bipedalism
• Enhanced hand movement
• Teeth became less specialized
• Culture

4

• Carbon dating
• A chemical analysis used to determine the age of
  organic materials based on their content of the
  radioisotope carbon 14
• Endosymbiosis
• Engulfing of single-celled organisms may have
  led to eukaryotic cell development
• Chloroplast mitochondria

5
Biological Changes over Time

• Biogeography
• World distribution of species
• Comparative morphology
• Similarities/differences in body plans of
  different organisms
• Vestigial organs organs that have no apparent
  function
• Tailbone
• Vestigial legs in whales
• Eye sockets in blind cave-dwelling worms

6
Biological Changes over Time

• Fossils
• Preserved skeletons of dead organisms
• Occurs when organisms become covered by sediments
  or ash
• Inorganic compounds replace minerals
• Similarities in DNA

7
Theories of Biological Change

• Cuvier
• Catastrophism no new species evolved
• Lamarck
• Acquired characteristics
• Theory of uniformity
• Gradual, uniformly repetitive change

8
Theories of Biological Change

• Malthus
• Carrying capacity
• Ecosystems can only maintain a particular
  population before a crash occurs
• Darwin
• Natural Selection
• Galapagos Islands
• Voyage on the Beagle
• On the Origin of Species

9
Natural Selection

• Selecting for inheritable traits that are
  advantageous to survival
• Evolutionary Fitness
• Refers to the ability of organisms to
  successfully reproduce and pass along important
  traits
• Examples
• Peppered moth
• Pesticide resistance
• Antibiotic resistance

10
Continental Drift

• Geological time scale
• Pangea
• Plate tectonics

11
Shared Ancestors

• Homologous structures
• Similarities in body parts between different
  groups

12
Shared Ancestors

• Morphological divergence
• A structure observed in a common ancestor changes
  through evolution so that descendants have
  different forms
• They have similar functions

13
Shared Ancestors

• Morphological convergence
• Dissimilar body parts become similar in remotely
  related organisms