Evolution & Population Genetics Flashcards
This fella came up with the classification of life & taxa that we use today!
Linnaeus
These two studied geological processes, and their constant nature, noting that environments were always changing.
Hutton & Lyell
Challenged the Earth being 6000 years old
This mathemetician & economist wrote an essay on populations outgrowing food supplies.
Malthus
This fella proposed that organisms can drive their own evolution by using or disusing a structure.
Lamarck
Is that true? Do giraffes have longer necks by stretching more?
NO - Longer necks=more food=more offspring
Darwin came along in the 1840’s and proposed:
Descent With Modification - every generation is slightly modified
Darwin Published his manifesto in…
1859
Why did Darwin rush to publish in 1859?
Because Wallace had an independent manuscript that would have given him all the credit!
Title of the Manifesto:
The Origin of Species (by means of natural selection) or The Preservation of Favoured Races in the Struggle for Life
Darwins ship?
HMS Beagle
Artifical Selection is represented by..
Domestication
What types might artifically select?
Horticulturists
Animal Breeders
Hobby Pigeons
The Domesitcation process is in essence:
Selective Breeding
Wild mustard is a good example of artificial selection in that…
It has been turned into cabbage, cauliflower, turnips, etc.
In order for artificial selection to work these 2 conditions must be met:
Trait must be variable
Trait must be heritable
If we can make big changes artificially in a short time…
Then same thing happens naturally over LONG periods of time. Nature can select favorable traits.
Darwins 4 Observations
Variability in character traits
Heritability of character traits
Overproduction of offspring (more than will survive)
Competition between offspring
Darwins inferences:
Survival of the fittest!
- Favourable variations survive longer, unfavourable not passed on as frequently.
- Unequal inheritance lead to survival of the fittest.
Changes in frequency of character traits in a population over time, will lead to a change in the…
Normal distribution bell-curve. Shifts indicate evolution! To the right or to the left.
From common ancestor organisms moved into..
Diverse environments
Diverse modifications
Hence tree of life
Evidence of relationships?
Fossil record!
The fossil record shows..
Gradual changes in body form from terrestrial to cetaceans.
Why can we not solely rely on the fossil record?
Missing Links
Evolution = (Tree wise)
Adaptive Radiation
Further evidence exists in these structures.
Homologous. Same pieces, different locations. Human/dog/whale/bat
Homologous structures are also evidence of…
Divergent Evolution
Where we put organisms in the Linnaean system relies heavily on:
Homology
Homologies may be _______, reduced because no longer needed.
Vestigial
Evidence of vestigial homologies?
Goosebumps. Whale pelvis. Also in embryonic structure!
The evidence to trump all evidence?
Molecular! DNA, RNA, Protein sequences
Using _____ sequences we can see how long ago species diverged.
Hemoglobin
We can trace the distance between organisms based on their amino acid ________.
Differences
Analogous structures represent different branches of the tree that look alike. Also called:
Convergent Evolution - came to same points by different routes
