BIO55: Population Genetics and Evolution

What is Evolution?

What is Evolution? I. Definitions

What is Evolution? I. Definitions A. youze guys

What is Evolution? I. Definitions A. youze guys B. References

What is Evolution? I. Definitions A. youze guys B. References 1. Darwin - "descent with modification" 2. Ridley - "change in a lineage of populations between generations" Futuyma - "a change in the properties of populations of organisms, or groups of such populations, over generations“ Freeman and Herron: “changes in allele frequencies over time"

What is Evolution? I. Definitions 2. Key Elements 1. Populations evolve – individuals develop.

What is Evolution? I. Definitions 2.Key Elements 2. - Evolution is an observable phenomenon: heritable change in a population over generations. This may be observed at the genetic level, in the genetic structure of the population, or may also be reflected in the physiological, morphological, or behavioral traits affected by this genetic change. We might term this "Lineage Evolution".

What is Evolution? I. Definitions 2.Key Elements 3. - with known, observable causes: the genetic structure of a population changes as a function of selection, drift, mutation, migration, and non-random mating.

What is Evolution? I. Definitions 2.Key Elements 4. - and known, observable results: As the genetic structure of a population changes over generations, it can become different (diverge) from other populations. These differences may mean that the populations can no longer breed, and they become biologically distinct entities - different species. We term this "Radiational Evolution". Why is reproductive isolation such a good definition of ‘species’, if by “species” we are trying to identify a biological unit that is different from another biological unit?

II. The History of Evolutionary Thought (Mayr, E. 1982. The Growth of Biological Thought) At one time, there were no scientists, theologians, or historians. There were just philosophers that studied everything, using one way of thinking. That has changed, as we will see....

II. The History of Evolutionary Thought A. Early Greeks Pantheon of meddlesome gods that controlled every aspect of nature and human experience; even took humans for mating (produced the heroes). Prometheus fashions humans out of earth and water, and Athena gives humankind a soul

II. The History of Evolutionary Thought B. Ionian School Anaximander (610-546 bc); life comes from water; first humans remained as embryos in fish and came forth as adults - had to come from other organisms because of prolonged developmental period of dependancy.

II. The History of Evolutionary Thought B. Ionian School Anaximander (610-546 bc); life comes from water; first humans remained as embryos in fish and came forth as adults - had to come from other organisms because of prolonged developmental period of dependancy.

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc)

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) -Valued observation and testing rather than pure logic - "cut-it-open-and-see"

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) -Valued observation and testing rather than pure logic - "cut-it-open-and-see" - Believed in use and disuse and inheritance of acquired traits; so accepted change within a "family". - Close to an evolutionary approach

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc)

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) - trained in Pythagorean school; philosopher not naturalist - UNIVERSAL PHILOSOPHY (four dogmas)

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) - trained in Pythagorean school; philosopher not naturalist - UNIVERSAL PHILOSOPHY (four dogmas) - Essentialism: (essences perfect; material world is an imperfect reflection of these perfect essences (eidos). Wall of the cave analogy; triangle example - Universal Harmony: essences form a perfect whole

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) - trained in Pythagorean school; philosopher not naturalist - UNIVERSAL PHILOSOPHY (four dogmas) - Essentialism: (essences perfect; material world is an imperfect reflection of these perfect essences (eidos). Wall of the cave analogy; triangle example - Universal Harmony: essences form a perfect whole - Demi-Urge: creative force that made the essences - Soul: non-corporeal "spark of life" in living systems; maximized in humans.

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) - trained in Pythagorean school; philosopher not naturalist - UNIVERSAL PHILOSOPHY (four dogmas) - Essentialism: (essences perfect; material world is an imperfect reflection of these perfect essences (eidos). Wall of the cave analogy; triangle example - Universal Harmony: essences form a perfect whole - Demi-Urge: creative force that made the essences - Soul: non-corporeal "spark of life" in living systems; maximized in humans. - became the bedrock of western civilization for 2000 years! Mayr states: "It took more than 2000 years for biology, under the influence of Darwin, to escape the paralyzing grip of essentialism...the rise of modern biology is, in part, the emancipation from Platonic thinking". hey!

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) 3. Aristotle (384-322 bc)

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) 3. Aristotle (384-322 bc) - Plato's student. The first great philosopher interested in biology. described 100’s of species and fossils

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) 3. Aristotle (384-322 bc) - Plato's student. The first great philosopher interested in biology. described 100’s of species and fossils - wrote books on anatomy, reproductive biology, and life histories

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) 3. Aristotle (384-322 bc) - Plato's student. The first great philosopher interested in biology. described 100’s of species and fossils - wrote books on anatomy, reproductive biology, and life histories - an empiricist; used observation to answer questions, not reason, alone - harmonious whole still static; fixed species from simple to complex in a great chain of being "Scala naturae"

II. The History of Evolutionary Thought C. 2nd Greek School 1. Hippocrates (450-377 bc) 2. Plato (427-347 bc) 3. Aristotle (384-322 bc) Major conclusion was Platonic essentialism

II. The History of Evolutionary Thought D. The Impact of Christianity World View: - Single complete, harmonious creation by Christian God

II. The History of Evolutionary Thought D. The Impact of Christianity World View: - Single complete, harmonious creation by Christian God - Static, unchanging

II. The History of Evolutionary Thought D. The Impact of Christianity World View: - Single complete, harmonious creation by Christian God - Static, unchanging - Plenitude: created in totality and perfection

II. The History of Evolutionary Thought D. The Impact of Christianity World View: - Single complete, harmonious creation by Christian God - Static, unchanging - Plenitude: created in totality and perfection - no breaks in Aristotle's scale of nature: extending from humans to priest to bishop, cardinal, pope, angels, God

II. The History of Evolutionary Thought E. The Renaissance (1400-1700)

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery - 1488 - Dias - Rounds Cape of Good Hope without burning! - 1492 - Columbus - "New World"

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 1. Nikoli Copernik (1473-1543)

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 1. Nikoli Copernik (1473-1543) 2. Galileo Galilei (1564-1642)

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 1. Nikoli Copernik (1473-1543) 2. Galileo Galilei (1564-1642) - nature is matter in motion, governed by mechanistic laws - "measure what can be measured and make measureable that which can not be measured"

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 1. Nikoli Copernik (1473-1543) 2. Galileo Galilei (1564-1642) - nature is matter in motion, governed by mechanistic laws - "measure what can be measured and make measureable that which can not be measured" - Empiricist - dependency on observation and testing, not authority. THE BIRTH OF THE EXPERIMENTAL METHOD. So now we have science, with reductionism and the experimental method

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 5. Isaac Newton (1642-1727)

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 5. Isaac Newton (1642-1727) - reasoned that the forces keeping planets in their orbits (corrected to ellipses by Kepler) was the same that caused attraction of terrestrial objects to earth (apple); and could be explained by Galileo’s physics and laws of motion. COMPARATIVE METHOD

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics 5. Isaac Newton (1642-1727) - reasoned that the forces keeping planets in their orbits (corrected to ellipses by Kepler) was the same that caused attraction of terrestrial objects to earth (apple); and could be explained by Galileo’s physics and laws of motion. COMPARATIVE METHOD - force varies as a product of the masses, and is inversely related to the square of the distance between them

II. The History of Evolutionary Thought E. The Renaissance (1400-1700) 1. Voyages of Discovery 2. Scientific Revolution a. Astronomy and Physics b. The Age of the Earth