Evolution :D

What are some examples of artificial selection?

. Cauliflower, broccoli, kale, and brussel sprouts come from wild mustard plant . The various dog breeds that originated from the wolf

What are the main points of Darwin's origin of species? (Be able to explain Darwin's diagram)

1) Variation exists in natural populations 2) More offspring are born than what the environment is able to support --> struggle to survive: competition 3) Differential survival - beneficial charcteristics for survival; adaptations = (ex. camouflage) --> will become more common in population 4) Differential reproduction - succeesful organisms live longer --> as adaptations become more common in population --> cahnes gene frequencies within population's gene pool --> emergence of new species

Hardy Weinberg

1) determine allele frequency in a population 2) estimate frequency of heterozygotes in a population 3) identify forces that cause evolution

What is diversifying selection?

A form of natural selection in which extreme values for a trait are favored over intermediate values

What is stabilizing selection?

A form of natural selection wherein individuals with moderate or average phenotypes are more likely to survive and reproduce

What is natural selection? What is an example of natural selection?

Adapting to fit the environment and increasing survival rate A population of mice with tan and black mice see a higher survival rate for black mice because they blend with the environment

What are the two ways speciation can occur?

Allopatric and sympatric

What does allele mean?

Alternative version of genes and are represented by letters Is a variant form of a gene (piece of DNA) at a single locus

What is mutation? What is an example of mutation?

Change in DNA sequence Hemophilia

What is genetic drift? What is an example of genetic drift?

Change in frequency of a gene variant in a population --> (not caused by environmental/ adaptive pressure) A population of rabbits with white and brown fur that due to genetic drift, rabbits with white fur are eliminated

What does heterozygous mean?

Different combination of DNA; two different alleles

What is artificial selection?

Evolutionary process in which humans consciously select for or against particular features in organisms

What is directional selection?

Form of natural selection in which a single phenotype is favored, causing the allele frequency to continuously shift in one direction, usually extreme phenotypes

What is allopatric speciation?

Geographic isolation which results in speciation

What is an example of stabilizing selection?

In a population of birds, the phenotype for a intermediate shade of feathers is favored

What is an example of diversifying selection?

In a population of birds, the phenotype for the extreme light and dark colored feathers is favored

What is an example of directional selection?

In a population of birds, the phenotype of light colored feathers is favored

What does adaptation mean?

Inherited traits that enhance an organisms ability to survive and reproduce

What are the driving forces for gene variability?

Mutation and gene flow

What are the four mechanisms of evolutionary change?

Mutation, gene flow, genetic drift, natural selection

What does natural selection mean?

Nature picks which traits are passed down

What is an example of bottleneck effect?

Northern elephant seals were hunted to almost extinction, approx only 20 left

What is the bottleneck effect?

Occurs after an event greatly reduces the size of a population leaving a small, random assortment of individuals; a lack of genetic variation

What is an example of founder's effect?

Polydatyly wich is commonly found among the Old Order Amish of Pennsylvania

What does fitness mean?

Reproductive success and how well an organism is adapted to environment

What does homozygous mean?

Same combination of DNA; the same alleles

What does speciation mean?

The process by which two populations of the same species become so different that they can no longer interbreed New species formed

What is sympatric speciation?

The process through which new species evolve from a single ancestral species while inhabiting the same geographic region

What is the founder effect?

The reduced genetic diversity that results when a small population is descended from a larger population

What is gene flow? What is an example of gene flow?

Transferring of alleles of genes from one population to another Geese from one population interbreeding with another population

What is an example of microevolution?

finches beaks; resistance to pesticide