What does Evolution Explain?
Leonardo da Vinci (1452 1519)
Nicholas Copernicus (1473 1543) The Scientific Revolution ca. 1543
The Scientific Revolution ca. 1543 Andreas Vesalius (1514-1564)
What does Evolution Explain? 1) Biological Patterns in Time
.only fiction and Hollywood can transcend time.
The geological record is arrayed in a sequential order, with older rocks positioned lower in the section, and younger rocks above
The simplest living organisms are single-celled creatures.
Modern stromatolites living in northern Australia
Stromatolites occur in some of the oldest Precambrian sedimentary rocks.
and the oldest fossils are of single-celled creatures like these stromatolites
The first animals with backbones (notochords) are found later, in Paleozoic rocks. Pikaia an ancient chordate, and a distant relative of the vertebrates, is found in Cambrian rocks.
Sauropod dinosaurs are only found in the Mesozoic
More familiar organisms, like this giant ground sloth, are from the Quaternary.the first people in North America probably saw these and may have eaten them
What does Evolution Explain? 2) Biological Patterns in Space
Glossopterus. A Permian plant fossil found in South America, Africa, India, Antarctica, and Australia.how did it achieve this distribution?
How did Glossopterus achieve this distribution?
Permian biogeography, and plate tectonics offer an explanation.
What does Evolution Explain? 3) Biological Patterns in Form (anatomy)
Pattern 3 (continued): Form Ontogeny: growth of a single individual (like you or me) from a single cell to adult.
Ontogeny: growth and differentiation of an individual from egg to adult
Could different species that resemble each other be related?
Georges-Louis Leclerc, Comte de Buffon 1707-1788 Jardin de Plantes Paris
Jardin de Plantes Paris
Hunterian Museum, London, ca. 1850
Jean-Baptiste Lamarck 1744-1839
George Cuvieer s Museum at the Jardin de Plantes, Pariss
1809-1882
Erasmus Darwin (1731-1802) Zootomia (Index Expurgatorius)
Variation occurs in all natural populations providing the basis for Natural Selection or Sexual Selection.
Darwinian evolution:
Darwinian evolution: Descent with modification
Darwinian evolution: Descent with modification Modification is driven by Natural Selection
Darwinian evolution: Descent with modification Modification is driven by Natural Selection Natural Selection acts on natural variation among individuals in a population
Darwinian evolution: Descent with modification Modification is driven by Natural Selection Natural Selection acts on natural variation among individuals in a population Natural Selection is non-directional
Darwinian evolution: Descent with modification Modification is driven by Natural Selection Natural Selection acts on natural variation among individuals in a population Natural Selection is non-directional What traits are selected for or against are contingent on the conditions for existence and reproductive success
Darwinian evolution: Descent with modification Modification is driven by Natural Selection Natural Selection acts on natural variation among individuals in a population Natural Selection is non-directional What traits are selected for or against are contingent on the conditions for existence and reproductive success Evolution is a highly contingent process
Why is Linnaeus famous?
Why is Linnaeus famous? Systema Naturae (1758)
Linnaean classification..
has a hard time with evolving organisms. Transitional forms from the fossil record spawned the theory of evolution, and now an evolutionary system of classification Archaeopteryx a Jurassic fossil with feathers and teeth.
Phylogenetic nomenclature is hierarchical.
Cladogram: evolutionary map of relationships, or phylogeny
Monophyletic group: an ancestor and ALL of its descendants
Quiz: What are the three patterns that evolution explains?
Phylogenetic classification is hierarchical.
.only Hollywood can transcend time.
A mammal, early in its ontogeny, showing many labeled characters
Synapomorphy: an evolutionary novelty that marks a monophyletic group; a new feature arising in the last common ancestor of that group. The Amniotic egg is a synapomorphy of this group, Amniota; the amniotic egg arose at node 1.