Evolution And Natural Selection

Question 1

Who Is Charles Darwin?

Answer 1

• Proposed that all living things have a common ancestor
• Populations with more advantageous traits are more likely to survive
• Over time, this leads to speciation
  Speciation is when populations evolve to become a new species

Question 2

What Is A Species?

Answer 2

A group of organisms that can interbreed and produce viable, fertile offspring under natural conditions

Question 3

Natural Selection

Answer 3

The process by which certain heritable traits become more or less common in a population over time, based on their impact on an organism’s survival and reproductive success

Question 4

Principles Of Natural Selection

Answer 4

Variation
Selection Pressure
Differentials In Survival And Reproduction
Heritability

Question 5

Variation

Answer 5

Individuals in populations exhibit variation in their traits, which they inherit from parents or arise through mutation

Question 6

Differentials In Survival And Reproduction

Answer 6

Individuals with traits that enhance their survival and reproductive success more likely to pass on traits to next generation

Question 7

Selection Pressure

Answer 7

The environment presents challenges or pressures that influence an organism’s ability to survive and reproduce

Question 8

Heriability

Answer 8

Advantageous traits are often heritable and are passed from parents to offspring through genes

Question 9

Biodiversity

Answer 9

Is the variety and variability of living organisms present in a particular habitat or ecosystem
It is measured in three levels EB, SB and GB

Question 10

Ecosystem Diversity
Species Diversity
Genetic Diversity

Answer 10

EB - The variety of ecosystems and habitats present in a given area or on a larger scale

SB - This refers to the variety and abundance of different species within a particular habitat or ecosystem

GB - The variation in genes within a species, encompassing the difference in genetic makeup among individuals within a population, and between populations of the same species (essential for adaption and long term survival of species)

Question 11

Mutations

Answer 11

Changes that occur in an organism’s DNA sequence.
Mutations introduce new genetic variation into a population which can be passed on to offspring

Question 12

Gene Flow

Answer 12

The movement of genes between populations

Occurs when individuals migrate from one population to another and interbreed with individuals from the recipient population

Introduces new genetic variation into a population, increasing genetic diversity

Question 13

Genetic Drift

Answer 13

The random fluctuation of allele frequencies within a population over time

More common in small populations

Can result in the loss or fixation of certain alleles

Question 14

Types Of Genetic Drift

Answer 14

Bottleneck-
Occurs when a population undergoes a catastrophic event

Founder-
Occurs when a small group of individuals establishes a new population in a new area geographically isolated from the original population

Question 15

Convergent Evolution

Answer 15

The process by which unrelated species independently evolve similar traits or adaptations in response to similar selection pressures

Question 16

Divergent Evolution

Answer 16

The process by which a single ancestral species evolves two or more distinct descendent species, each with unique traits and adaptations

Question 17

Co-Evolution

Answer 17

Two species evolve together due to their close relationship. When one evolves, do does the other

Question 18

Homologous Vs Analogous Structures

Answer 18

Homo-
- Shares common ancestor
- May have different functions
- Usually arises with Divergent Evolution

Ana-
- Does not share common ancestor
- Similar function/purpose
- Usually arises with Convergent Evolution

Question 19

Phylogenetic Trees

Answer 19

Diagram that represents the evolutionary pathways and relatedness between species
The more recent the common ancestor (the node) the more closely related two species are

Question 20

VSDH

Answer 20

Variation-
Individuals in populations exhibit variation in their traits, which they inherit from parents or arise through mutation

Selection Pressure-
The environment presents challenges or pressures that influence an organism’s ability to survive and reproduce

Differentials In Survival And Reproduction-
Individuals with traits that enhance their survival and reproductive success more likely to pass on traits to next generation

Heritability-
Advantageous traits are often heritable and are passed from parents to offspring through genes