Biology Exam 1: Evolution Flashcards
Lectures 1-4
Cardia bifida example for why knowledge of evolution is important in medicine
Humans are bilateral symmetric organisms (mirrored development on both sides of the body). The hearth results from the fusion of two proto-hearts thus explaining WHY cardia bifida exists.
Hernia example for why knowledge of evolution is important
Hernias are 25x more common in men than women because the descent of the testes through the abdominal wall causing an area of weakness, making men susceptible to hernias
What is the unifying theme in biology?
evolution
Untrained assumption: disease causing organisms will change over time to become more benign. Reality:
disease causing organisms are constantly evolving to become more fit, thus becoming more dangerous to their hosts
Untrained assumption: Humans will eventually evolve to be resistant to disease causing organisms
Disease causing organisms can evolve much faster than humans because of their low generation time, meaning that over time humans will become less resistant due to more dangerous bacteria
When did antibiotics first start losing their effectiveness?
1950’s
Factors that lead to antibiotic resistance: (5)
- over prescribing
- inaccurate prescribing
- early discontinuation of use
- high density low sanitary living conditions
- extreme overuse in livestock industry
Give two examples of Evolutionary anatomy
- Wisdom teeth impaction because of the shrinking of human jaws
- the complexity of the cranial nerves because as the muscles and bones of the skull shifted, the nerves attached to these structures shifted as well (cranial nerve XI is associated with shoulder shrugging because your collarbone was part of your gill covering millions of years ago
What organism is used as a model for Alzheimer’s research? What portion of our genome is identical to this organism?
yeast. 2/3
Assumption of population biology: biological populations will evolve to restrain their own reproduction so as to benefit the species.
Reality: every organism for him/herself: the evolutionary goal is to pass on one’s genes
With what two scientists and when did our modern understanding of evolution begin?
Buffon and his protege Lamarck in the 1700’s
Why were the groundbreaking ideas of Buffon and Lamarck quickly rejected during their time and by whom were they rejected best?
Couvier:
- tinkering with a complex and fantastic machine suck as the human hand can only do more harm than good
- Fossils=the aftermath of the biblical flood. (Couvier was the first person to understand extinction in Western culture)
- Egyptian cat v. modern cat (~5000 years): found no change
- People accepted biblical creation
Who created a date of creation based on theology and what was it? Who changes this idea?
James Usher: Oct 23, 4004 BC at 9:00 am.
James Hutton
Hadrian’s wall
Hutton’s wall had been there for 1500 years and was relatively perfect. If 1500 years didn’t change a wall, how long would it take to carve a canyon? Thus he realized the earth had to be incredibly old.
Hutton’s unconformity
many layers, some vertical and some horizontal. Layers showed how old earth must be and the different orientations ____________.
Darwin was not the first to hypothesize evolution. What did he do?
He came up with the mechanism for evolutionary change: natural selection
In what year did Darwin publish the Origin of Species?
1859
Law of fossil succession (+example)
If two species are evolutionarily related, we should be able to find a pattern where the extant (living) and extinct (dead) forms live. Example: Glyptodont and armadillo
Two v important questions Darwin had to be able to answer if people were going to believe him
- HOW do species change?
2. WHY do species change?
________ keeps population size in check
competition
What happens to species that allows them to better compete for limited resources?
They change (WHY?)
The first evolutionist who confidently and publicly stated his ideas about the processes leading to biological change
Lamarck, Buffon’s protege. Buffon was one of the first scientists to postulate that life was not fixed.
When did the idea of evolution first begin?
1700’s
Who was responsible for the dismantling of early evolution?
Couvier. He was the first comparative anatomist and the fist person to dismantle evolution with something other than the Bible