Lecture 3: History of Evolutionary Thought Flashcards
Darwin and Evolutionary Thinking before the Modern Synthesis
one of the most influential texts of this century.
Origin of Species by Charles Darwin
What was Charles Darwin’s initial career pursuit?
Medicine
Where did Charles Darwin study botany?
Christ’s College, Cambridge
Who encouraged Darwin to join the Voyage of the Beagle?
Rev. John Henslow
Which ship did Charles Darwin embark on for his scientific expedition?
HMS Beagle
Who and what was Charles Darwin’s father and grandfather’s profession?
- Richard Darwin (father)
- Erasmus Darwin (grandfather)
- Doctors
What subject did Charles Darwin pursue a passionate interest in while at Christ’s College, Cambridge?
Natural History
Where did Charles Darwin make a major find of fossil bones during his voyage?
Punta Alta, Patagonia
What expertise did Darwin have during the voyage?
Geology
beetle collecting
marine
invertebrate dissection
Where are the Galapagos Islands located?
Pacific Ocean, west of continental Ecuador
What did Darwin conclude about the populations of species on the Galapagos Islands?
They descended from a common ancestor and were evolving.
What did Darwin question after observing the populations on the Galapagos Islands?
The stability of the concept of a “species.”
where did Darwin first observe mockingbirds that sparked his interest?
Galápagos, near Sappho Cove on Chatham Island (now Isla San Cristóbal)
What did Darwin notice about the mockingbirds on different islands in the Galápagos?
They differed slightly in size, shape, and coloration.
Who informed Darwin that tortoises also differed from island to island in the Galápagos?
Nicolas Lawson, acting Governor of Galápagos
What did Darwin speculate about the distribution of mockingbirds and tortoises towards the end of the voyage?
Their distribution might undermine the stability of species, suggesting that species are not fixed entities but change over time.
What did Darwin conclude about the mockingbirds after observing them on different islands?
They must have shared a common ancestor and were not independently created.
What did exposure to animal diversity during the voyage lead Darwin to conclude about species?
1) “Species” are not immutable fixed entities
2) Organisms are related by common ancestry (tree-like branching)
3) They are changing and branching in response to the environment (“Adaptation”)
Who did Darwin marry upon his return to England?
Emma Wedgewood
What historical developments provided the scientific context for the development of Darwin’s theory of evolution?
Discoveries in geology, including the understanding that the Earth is older than previously thought, and the fossil record showing changes in species over time.
What influential scientific theory did Lamarck propose before Darwin?
The inheritance of acquired characteristics.
Who influenced Darwin’s idea of competition and the struggle for survival?
Thomas Malthus, through his work “Essay on the Principle of Population.”
What idea did Darwin develop from Malthus’ work?
The concept of competition and the “struggle for survival” as components of natural selection.
Who independently came up with the idea of natural selection around the same time as Darwin?
Alfred Russel Wallace
What did Darwin and Wallace decide to do after learning about each other’s work?
joint presentation at the Linnean Society in 1858.
What was the title of Alfred Russel Wallace’s manuscript that he sent to Darwin?
“On the Tendency of Varieties to Depart Indefinitely from the Original Type”
When did Darwin publish “On the Origin of Species”?
1859
What are Darwin’s main points in “On the Origin of Species”?
1) Organisms evolve
2) Common descent: species arise from common ancestors
3) Gradualism: changes occur gradually
4) Population speciation: change in proportions of individuals with a trait in a population
5) Natural selection as the mechanism of adaptive evolution.
What was Lamarck’s view on the pattern of evolution?
Linear progression, often depicted as a “ladder of life” or “great chain of being.”
How did Darwin view the pattern of evolution?
As a tree-like branching process.
What was Lamarck’s proposed mechanism of evolution?
Inheritance of acquired traits at the individual level.
What was Darwin’s proposed mechanism of evolution?
Evolution at the population level via natural selection.