Lecture 19- Darwinian Evolution Flashcards
What did James Hutton theorize?
The concept of gradualism (idea that the world changes in slow, gradual processes such as erosion)
What does the concept of uniformitarianism state?
The natural laws that operate in the present have always been in operation. The world is always changing and life is always changing.
Which scientist first suggested a mechanism for evolution?
Jean-Baptiste Lamarck (species evolve through inheritance of acquired characteristics)
How is evolution defined?
Changes in alleles over time in a population
Who was the economist that influenced Darwin? What were his observations?
Thomas Malthus found that natural resources are limited and organisms have to compete for resources (limits population growth)
What did Carolus Linnaeus develop? Why is it significant?
Developed binomial nomenclature which allows for a systemic classification of organisms
How is population defined?
A group of the same species that are interbreeding and sharing a gene pool
Which scientist theorized the concept of uniformitarianism?
Charles Lyell
Which scientist proposed the natural selection mechanism of evolution?
Charles Darwin
What is natural selection?
Evolutionary mechanism proposed by Darwin and Wallace by which organisms better adapted to their environment tend to survive and produce more offspring
Which scientist hypothesized gradualism?
James Hutton
What are homologous structures?
Organs or skeletal elements of organisms that, by virtue of their similarity, suggest their connection to a common ancestor
What were Darwin’s four major observations?
More offspring are produced than can survive (overproduction), unequal ability to survive and reproduce, members of a population often vary greatly in their traits (variation), non-random survival/reproduction (best adapted individuals with the best phenotypes produce the most offspring)
What does it mean to be fit from a biological perspective?
An organism that is fit has a lot of offspring
What does the gradualism hypothesis state?
Evolution proceeds chiefly by the accumulation of gradual changes (observable processes are small but accumulate over time)
