C4 & C5 (Microevolution and Speciation) Flashcards
Simply put as the evolution on a small
scale within a single population
microevolution
It is the generation to generation
change in frequencies of alleles within a
population
microevolution
Frequency of alleles in a
population stays the same
generation after generation
unless acted upon by some
outside force.
HARDY WEINBERG THEORY
A ____is often defined as a group of individuals that actually or potentially
interbreed in nature
species
In this sense, a _____is the biggest gene pool possible under natural
conditions
species
Explain and correct the misconception about species:
clue: Species are distinct natural entities, with a clear definition, that can be easily recognized by
anyone.
Good job
a lineage splitting event that produces two
or more separate species
speciation
In ______, an ancestral species splits into
two or more descendant species that are
genetically different from one another and
can no longer interbreed.
speciation
Different species are unable to interbreed and produce healthy, fertile offspring due to barriers called
mechanisms of reproductive isolation
enumerate the prezygotic barriers
*
Geographical Isolation
*
Temporal Isolation
*
Behavioral Isolation
*
Gametic Isolation
*
Mechanical Isolation
enumerate the postzygotic barriers
*
Mixed set of chromosomes
*
Unhealthy individual
*
Infertility
Populations are prevented from
interbreeding by habitat isolation.
Geographical Isolation
Populations are prevented
from interbreeding by the
difference in their mating or
reproduction time
Temporal Isolation
*
Two species might have
different courtship behaviors
or mate preferences and thus
find each other
“
Behavioral Isolation
*
Two species might produce
egg and sperm cells that
can’t combine in
fertilization, even if they
meet up through mating.
Gametic
Isolation
*
Two species might have
bodies or reproductive
structures that simply don’t fit
together.
Mechanical Isolation
*
What are the modes of speciation
Allopatric
Peripatric
Parapatric
Sympatric
_____ occurs when a
species separates into two separate
groups which are isolated from one
another
Allopatric speciation
In this speciation, Each species develops differently
based on the demands of their
unique habitat or the genetic
characteristics of the group that are
passed on to offspring
Allopatric speciation
Happens when small groups of individuals
break off from the larger group and form a
new species
Peripatric
Speciation
In this speciation, one group is much smaller than the
other and the unique characteristics of the
smaller groups are passed on to future
generations of the group, making those
traits more common among that group and
distinguishing it from the others.
Peripatric
Speciation
A species is spread out over a large
geographic area.
Parapatric
Speciation
Although it is possible for any
member of the species to mate with
another member, individuals only
mate with those in their own
geographic region.
Parapatric
Speciation
Instead of being separated by a
physical barrier, the species are
separated by differences in the same
environment.
Parapatric
Speciation
occurs when
there are no physical barriers
preventing any members of a
species from mating with another,
and all members are in close
proximity to one another.
Sympatric speciation
A new species, perhaps based on a
different food source or
characteristic, seems to develop
spontaneously.
Sympatric speciation