Evolution Flashcards
Neutral Mutation
A mutation that doesn’t result in any advantage or disadvantage
Harmful Mutation
A mutation that reduces the reproductive success of an organism
Beneficial Mutation
A mutation that increases reproductive success so they are favoured by natural selection
Artificial Selection
Directed breeding to obtain a specific trait
What are the 2 advantages to artificial selection?
1) Can achieve the most desirable traits
2) Variability
What are the 3 disadvantages of artificial selection?
1) Eliminates traits
2) No variability
3) A undesirable trait may become desirable over time
Catastrophism
The theory that fossils were caused by a series of global catastrophes that wiped out most species on Earth
Uniformitarianism
The theory that geological changes are slow and gradual and that natural processes haven’t changed overtime
Homologous
A structure with a common evolutionary origin that may serve different functions in modern species
Example: Bat wing and human arm
Analogous
A structure that performs the same function as another but isn’t similar in origin
Example: Bird and insect wings
Vestigal
A structure in an organism that has lost all or most of its original function in the course of evolution
Example: Human Appendix
Genetic Drift
When chance events cause changes in frequencies of alleles in a population; more prominent in small populations
Genetic Bottleneck
A dramatic often temporary decrease in population size causing significant genetic drift
Species
All organisms capable of breeding freely with each other under natural conditions
Speciation
The formation of a new species
Evolution
The scientific theory that describes changes in species overtime and their shared ancestry
What are Darwins 5 Key Points of Evolution?
1) In each generation populations produce more offspring than there are adults
2) Populations do not continue to grow in size
3) Food and other resources are limited
4) Individuals within all populations vary
5) Many variations are inheritable
Directional Selection
Selection that favours a trait that has significantly increased or decreased compared to the population average
Stabililing Selection
Selection that only favours the traits that the majority population has
Disruptive Selection
Selection thar favours two or more variations of a trait that differ from the population average
Sexual Selection
Selection that favours your ability to reproduce
What are the 5 pieces of evidence for evolution?
1) Palaeontology
2) Comparative Anatomy
3) Embryology
4) Comparative Biochemistry
5) Geographical Distribution
Explain 2 of the pieces of evidence for evolution. (Palaeontology and Comparative Biochemistry)
Palaeontology: The study of prehistoric life through fossils. The fact that not all organisms appear in fossils supports the fact that species evolve over time
Comparative Biochemistry: Comparing DNA and amino acid sequences from different animals to see how closely related species are. The more closely related the more similar their biogeochemical makeup.
Domestication
The changing of members of a species to suit human needs through controlled captive breeding
