Evolution
22/11/2022 13:09
How does it occur?
• The goal of life is to survive and pass on genes to the
next generation
• Those individuals who have advantageous due to their
genes survive and pass those genes on ti the next
generation
• This individuals who don’t have advantageous traits do
not survive and do not pass on their genes to the next
generation
Why does it occur?
• Evolution occurs because abiotic and biotic factors and
constantly changing
• This means individuals or groups who have different
advantageous/adaptive traits survive
• This causes species to change over long periods of time
What is a species?
• Species is a group of organisms that can breed with each
other to produce fertile young and are reproductively
separate from other groups
• Speciation is the formation of new and distinct species
due to the gradual changes from evolution
• When demes become reproductively isolated from their
ancestral population they become a new population
Types of speciation
• Allopatric - where a population is separated, each gene
then becomes reproductively isolated from one another
causing each population to diverge into different
species.
• Peripatric - where a deme emigrate into a new niche,
adapts to that new niche, becomes reproductively
isolated and diverges into a new species.
• Parapatric - where a deme occupies and adjacent to the
original population, adapts to the new niche, becomes
reproductively isolated and diverges into a new species.
• Sympatric - where individuals within a population show
genetic polymorphism and reproductively isolate from
the original population through sexual selection for
22/11/2022 13:09
How does it occur?
• The goal of life is to survive and pass on genes to the
next generation
• Those individuals who have advantageous due to their
genes survive and pass those genes on ti the next
generation
• This individuals who don’t have advantageous traits do
not survive and do not pass on their genes to the next
generation
Why does it occur?
• Evolution occurs because abiotic and biotic factors and
constantly changing
• This means individuals or groups who have different
advantageous/adaptive traits survive
• This causes species to change over long periods of time
What is a species?
• Species is a group of organisms that can breed with each
other to produce fertile young and are reproductively
separate from other groups
• Speciation is the formation of new and distinct species
due to the gradual changes from evolution
• When demes become reproductively isolated from their
ancestral population they become a new population
Types of speciation
• Allopatric - where a population is separated, each gene
then becomes reproductively isolated from one another
causing each population to diverge into different
species.
• Peripatric - where a deme emigrate into a new niche,
adapts to that new niche, becomes reproductively
isolated and diverges into a new species.
• Parapatric - where a deme occupies and adjacent to the
original population, adapts to the new niche, becomes
reproductively isolated and diverges into a new species.
• Sympatric - where individuals within a population show
genetic polymorphism and reproductively isolate from
the original population through sexual selection for
