4.1.7 - Reproductive Isolation Flashcards
What Is Meant Be Species?
Group of similar organisms that can reproduce to give fertile offspring.
What Happens During Reproductive Isolation?
Changes in alleles and phenotypes of the population prevent them from successfully breeding together.
What Are Examples Of Allele Or Phenotype Changes That Can Lead To Reproductive Isolation?
(3 Points)
~ Seasonal changes.
~ Mechanical changes.
~ Behaviour changes.
How Do Seasonal Changes Lead To Reproductive Isolation?
(2 Points)
~ Individuals from the same population develop different flowering or mating seasons.
~ Or become sexually active at different times of the year.
How Do Mechanical Changes Lead To Reproductive Isolation?
Changes in genitalia prevent successful mating.
How Do Behavioural Changes Lead To Reproductive Isolation?
A group of individuals develop courtship rituals that aren’t attractive to the main population.
What Are Two Factors That Could Bring About Changes Leading To Reproductive Isolation?
(2 Points)
~ Geographic isolation, isolating populations.
~ Random mutations producing new, different alleles in a population.
How Does Geographical Isolation Occur?
When a physical barrier divides a population of a species.
What Is Speciation?
The development of a new species.
What Is Speciation & When Can It Occur?
Occurs when populations of a species become separated by geographical barriers, preventing gene exchange.
What Happens To The Gene Pools Of Geographically Isolated Populations?
Different selection pressures and random mutations change the gene pools and allele frequencies within each population, leading to divergence.
How Do Changes In Alleles & Genes Affect Populations?
Changes affect the phenotypes present in both populations, leading to physiological, behavioral, and anatomical differences over time.
What Role Do Random Mutations Play In Speciation?
They change allele frequencies, contributing to divergence between the populations.
