Microevolution Christopherson What is Microevolution Change in a

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Microevolution Christopherson

Microevolution Christopherson

What is Microevolution? Change in a populations alleles over a period of time Calculate

What is Microevolution? Change in a populations alleles over a period of time Calculate allele frequencies

Allele Two different forms of a gene (portion of DNA that codes for a

Allele Two different forms of a gene (portion of DNA that codes for a trait)

Three different combinations of Alleles Homozygous Dominant: DD Heterozygous: Dd Homozygous Recessive: dd

Three different combinations of Alleles Homozygous Dominant: DD Heterozygous: Dd Homozygous Recessive: dd

Allele Frequencies A measure of how often (frequency) an allele is apparent in a

Allele Frequencies A measure of how often (frequency) an allele is apparent in a population. Dark Brown=D Tan=d

Allele Frequencies A measure of how often (frequency) an allele is apparent in a

Allele Frequencies A measure of how often (frequency) an allele is apparent in a population. Dark Brown=D Tan=d Dd dd DD DD dd DD Dd dd dd DD Dd Dd Dd dd DD dd

Allele Frequencies How many D? Dd dd DD DD dd DD Dd dd dd

Allele Frequencies How many D? Dd dd DD DD dd DD Dd dd dd DD Dd Dd Dd dd DD dd

Allele Frequencies How many D? 18 Dd dd DD DD dd DD Dd dd

Allele Frequencies How many D? 18 Dd dd DD DD dd DD Dd dd dd DD Dd Dd Dd dd DD dd

Allele Frequencies How many D? 18 How many d? Dd dd DD DD dd

Allele Frequencies How many D? 18 How many d? Dd dd DD DD dd DD Dd dd dd DD Dd Dd Dd dd DD dd

Allele Frequencies How many D? 18 How many d? 22 Dd dd DD DD

Allele Frequencies How many D? 18 How many d? 22 Dd dd DD DD dd DD Dd dd dd DD Dd Dd Dd dd DD dd

Allele Frequencies Gene Pool All of the genes in a population Dd dd DD

Allele Frequencies Gene Pool All of the genes in a population Dd dd DD DD dd DD Dd dd dd DD Dd Dd Dd dd DD dd

What is Natural Selection? “Survival of the Fittest” The best adapted organism will survive

What is Natural Selection? “Survival of the Fittest” The best adapted organism will survive and pass traits onto offspring

Natural Selection Flowchart

Natural Selection Flowchart

Observation #1 Every population has the ability to grow

Observation #1 Every population has the ability to grow

Observation #2 Every population has limited resources

Observation #2 Every population has limited resources

Conclusion #1 Competition for resources Hyena

Conclusion #1 Competition for resources Hyena

Observation #3 Every individual in a population is different in structure and behavior. Ex-pattern,

Observation #3 Every individual in a population is different in structure and behavior. Ex-pattern, speed, agility, etc

Conclusion #2 Natural Selection-Survival of the Fittest: Best adapted organism will survive

Conclusion #2 Natural Selection-Survival of the Fittest: Best adapted organism will survive

Observation #4 Survivors will pass their traits on to their offspring.

Observation #4 Survivors will pass their traits on to their offspring.

Conclusion #3 Evolution has occurred. There could be a change to the population.

Conclusion #3 Evolution has occurred. There could be a change to the population.

Natural Selection Video Watch video. It is a bit long, but has great information.

Natural Selection Video Watch video. It is a bit long, but has great information. Notice the use of gel electrophoresis. If it doesn’t work, try another browser.

Natural Selection Depends on Two Things 1. Survival An organism must stay alive in

Natural Selection Depends on Two Things 1. Survival An organism must stay alive in a world with disease, predators and limited resources (food, water, territory)

Sarcastic Fringe Head (Watch Video) Due to limited space in the ocean, Fringe Head

Sarcastic Fringe Head (Watch Video) Due to limited space in the ocean, Fringe Head must “fight” to defend their territory or to obtain food. The Fringe Head that is most fit will obtain or keep the territory.

Orchid Mantis (Watch Video) Orchid mantis uses camouflage to obtain its food. It has

Orchid Mantis (Watch Video) Orchid mantis uses camouflage to obtain its food. It has adapted over time to blend into orchids.

Cuttlefish (Watch Video) Cuttlefish are just plain amazing. They have adapted to be awesome!

Cuttlefish (Watch Video) Cuttlefish are just plain amazing. They have adapted to be awesome!

Once an organism survives, it needs to pass along its genes. This leads to

Once an organism survives, it needs to pass along its genes. This leads to #2….

Natural Selection Depends on Two Things 2. Sex Only the “best” organisms or the

Natural Selection Depends on Two Things 2. Sex Only the “best” organisms or the survivors get the chance to mate and pass on their genes.

Darwin’s Beetle (Watch Video) The male beetle has to fight other males to get

Darwin’s Beetle (Watch Video) The male beetle has to fight other males to get to the female. The “Best” male wins. He gets to pass on his genes.

Birds (Watch Video) Male birds have some of the most beautiful colors, elaborate songs,

Birds (Watch Video) Male birds have some of the most beautiful colors, elaborate songs, and fancy dances. All of this is to attract a female. It is called sexual selection. The “Best” male wins. He gets to pass on his genes. The bright blue bird is the male. The female is the plain one. She is this way because she will spend time at the nest. If she was bright, predators would see her and eat her eggs or young.

Giant Bullfrog (Watch Video) The male bullfrogs fight for the ladies. The best male

Giant Bullfrog (Watch Video) The male bullfrogs fight for the ladies. The best male wins. He gets to pass on his genes. Frogs undergo external fertilization. The male holds on to the female (typically bigger) and waits for her to lay her eggs. He then deposits his sperm.