Flashcards in Bio I Evolution 4.1-4.2 Deck (28):
The ability to survive and reproduce in specific environment
What is struggle for existence?
Members of species compete against each other for resources
What is a cladogram
Branching diagram which shows relationship between species
What are the 4 sources of evidence for evolution?
1. Fossil record
2. Geographic distribution of organisms
3. Comparative anatomy
Why can't fossil records be fully reliable?
Don't have fossils for everything
What does fossil record show?
How earth has changed over time
What is the study of an organism before birth?
Homologous structures have...
Same structure, different function
Analogous structures have...
Different structure, same functions
An insect wing and a bird wing are...
A bat wing and a human arm are...
What are vestigial structures?
Structures that serve no useful function
How do vestigial structures provide evolution evidence?
They were once used in a common ancester
What is biochemistry?
Comparing proteins in different organisms
What is comparing proteins in different organisms?
Organization of classification in taxonomy...
What is a gene pool?
All genes present in a population
What are the three main sources of variation?
Mutations, genetic recombination in sexual reproduction, and lateral gene transfer in asexual reproduction
What is the original source of genetic variation?
Why does genetic recombination occur?
Crossing over during meiosis
What three things affect genetic variation?
1. Genetic drift
2. Gene flow
3. Natural selection
Bottle neck effect
Natural disaster changes population gene pool
New population established results in loss of genetic variation
What is gene flow?
Migration of individuals between populations
Formation of a new species
What are the three types of isolation mechanisms?
List and explain the types of selection (think bell graph)
- directional: one of the extremes selected for, other against
- stabilizing: middle trait selected for
- disruptive selection: extremes selected for, middle against