Evolution In The Past Flashcards
(41 cards)
What is Mutation?
Mutation is anything that disrupts your normal genes/pigments (A change in the genotype/DNA of an organism)
Effects of Mutation
- Mutation create a continual supply of new genetic information
- Has an immediate and direct effect on individuals
- Influences/changes the genes of further generations
Why Do Organisms Mutate?
Organisms mutate to survive/adapt better in their environment
Mutation Types
- Neutral
- Harmful
- Beneficial
Neutral Mutation
Provides no benefit or harm
e.x occurrence of freckles due to the sun
Harmful Mutation
Reduce the reproductive success
e.x genetic disorder
Beneficial Mutation
Changes the individual’s phenotype to provide an advantage
(e.x The Rock Pocket Mouse: the furs of the mouses mutate overtime to blend in w/the background. Their fur changes/mutates depending on if the volcano erupts. It is a beneficial mutation because the changes helps them blend in with the background and hide from predators)
Advantages of Selective Breeding/ Artificial Selection
- Provides variation in but not due to environmental pressures
- We are able to control what and who we want to mate with
- Increase the population
Example of Artificial Selection
- Dogs and cats
- Because tigers are going extinct, scientists are breeding the tigers with the lions to save the tiger genes
Limitations of Selective Breeding/ Artificial Selection
- Limit the genetic pool. AKA no genetic variety
- Will be breeding siblings together
- Population easily wiped out by diseases etc. because everyone in the pool has the same/similar genes
2 of Lamarck’s Theory: Adaption: Why do species change over time?
- Use and Disuse
2. Inheritance of Acquired Characteristics
Use and Disuse
Structures that were used often became stronger and larger than those that were not used became smaller and weaker
Example of Use and Disuse
Tailbones in humans: we don’t have a tail so there is no use of a tailbone
Inheritance of Acquired Characterstics
Individuals could pass on advantageous characteristics that they had acquired during their lives onto their offsprings
Example of Inheritance of Acquired Characterstics
If the climate cooled, the animals might respond by growing a thicker coat of hair and would pass on this acquired characteristics to their offsprings
Lamarck’s Giraffes
Example of use and adaption:
- The giraffe had an originally short-necked ancestor, but the giraffe eats leaves that grows high on trees. Because the giraffe constantly used it’s neck to reach for leaves that are high, the neck stretches overtime until it became progressively longer
Flaws in Lamarck’s Theory
Not all of the traits from the parents can be passed onto their future generation
(e.x. You can stretch your muscles but that does not change the DNA that will be inherited; only a mutation will do that)
Ideas for Further Research Concluded from Lamarck
- All species evolve over time
- A specie evolves in response to its environment and becomes better adapted
- Changes are passed on from generation to generation
Who was Charles Darwin?
- English Naturalist
- The Origin of Species
- Father of Evolution
- Voyage on the Beagle
when he was 22 to find the evidence to propose a hypothesis about how life changes over time
What is Natural Variation
Differences among individuals of a species
What is Artificial Selection
When nature provides the variation among different organisms, and humans select those variation they find useful and continues
What is Artificial Selection?
When nature provides the variation among different organisms, and humans select those variation they find useful and continues to breed them
What Is The Main Force Behind Evolution?
Natural Selection
2 Main Drives for Evolution
- The struggle for existence
2. Survival of the fittest
