This document discusses macroevolution and microevolution. Microevolution involves changes in allele frequencies within a population over a short time due to factors like mutation, gene flow, genetic drift, non-random mating, and natural selection. These small changes can accumulate over long periods to result in macroevolution, where new species, genera, and higher taxonomic groups emerge due to reproductive isolation and genetic divergence between populations. Macroevolution can occur through both allopatric speciation, where populations are geographically isolated, or sympatric speciation within overlapping populations.

2. 
Origin of Species: Macro and
Microevolution

3. 
All evolution is based on changes in the
information stored in DNA- information
that guides development and leads to
distinctive body forms, metabolic
products, and behavior patterns.

4. 
1. Microevolution
2. Macroevolution
Two Levels of Evolution

5. 
A change of allele frequencies in a
population over a short period of
time.
The basis for all large-scale or
macroevolution.
Microevolution

6. 
5 Agents of Change that can Alter Allele
Frequencies
1. Mutation
2. Gene Flow
3. Genetic Drift
4. Non-random Mating
5. Natural Selection
Microevolution

7. 
Any permanent alteration in the makeup of DNA.
*they must be heritable
* base pair deletion, translocation, etc.
* most do nothing , a few are harmful, rarely are
they beneficial
*these mutations are not working to further
survival and reproduction
*these mutations are not likely to account for a
change in allele frequency
*these good mutations bring new genetic
information into the genetic pool
Mutation

8. 
A change in allele frequency that can occur
when mating with members from another
population occurs.
*Migration- the movement of individuals
from one population into the territory of
another.
Gene Flow

9. 

10. 

11. 
Change in allele frequencies of a gene
pool due to chance.
Example: Natural disaster, weather change
Genetic Drift

12. 
 The change in allele frequency in a population due to
chance following a sharp reduction in the population
size.
Bottleneck Effect

13. 

14. 
When a small portion of a
population migrates to another
area, starting a new population.
Founder Effect

15. 

16. 
Individuals do not choose mates randomly
1. Assortive mating- individuals tend to mate
with those with the same phenotype.
2. Sexual selection- males compete for the
right to reproduce and females choose to
mate with males possessing a particular
phenotype
Non-random Mating

17. 
Results in adaptation of a population to the
environment.
Survival of the fittest
Traits of those who are more successful in
reproducing will become widespread in a
population, the alleles that bring about these
traits will bring about these traits and will
increase in frequency from one generation to the
next.
Acts on individuals, but only population evolve
Natural Selection

18. 
1. Directional selection- individuals on one end of a
phenotypic range are favored
2. Disruptive selection- when environment selects
individuals on both extremes
3. Stabilizing selection- favors more intermediate
forms , tending to reduce phenotypic variation
4. Sexual selection-enhances mating, can lead to
sexual dimorphism(distinction of males and females
by secondary sexual characteristics).
Types of Natural
Selection

19. 
 Intrasexual selection- same sex competing for mates
 Intersexual selection- mate choice, females choose
“sexier” male.
 Natural selection does not result in perfect organism.
Can act on variations in the populations. Also chance
events affects populations evolution history.

20. 
 It happens upper level of species and create a new
families, order, genra
 Created by population fragmentation and genetic
divergence
 Many microevolution are add in it.
Macroevolution

21. 
1. Reproductive Isolation
2. Allopatric Speciation
3. Sympatric Speciation
Causes of Macroevolution

22. 
 is the existence of biological factors (barriers) that
impede two species from producing viable, fertile
offspring
 Reproductive isolation can be classified by whether
factors act before or after fertilization
Reproductive Isolation

23. 
Individuals
of diffrents
species
Mating
attempt
Fertilization
Viable
fertile
offspring
Prezygotic Barriers Postzygotic Barriers
Habitat
isolation
Temporal
isolation
Behavioral
isolation
Mechanical
isolation
Gametic isolation
Reduced
hybrid
viability
Reduced
hybrid
fertility
Hybrid
breakdown

24. 
Reproductive isolation between populations
generally increases as the distance between
them increases
For example, reproductive isolation
increases between dusky salamanders that
live further apart

25. 
 gene flow is interrupted or reduced when a
population is divided into geographically isolated
subpopulations
 Different homeland
For example, the flightless cormorant of the
Galápagos likely originated from a flying species
on the mainland
Allopatric Speciation

26. 
 15 pairs of sibling species of snapping shrimp
(Alpheus) are separated by the Isthmus of Panama
 These species originated 9 to 13 million years ago,
when the Isthmus of Panama formed and separated
the Atlantic and Pacific waters
Evidence of Allopatric
Speciation

27. 
A. FORMUSOS A. NUTTINGI
Atlantic Ocean
Isthmus of Panama
Pacific Ocean
A. panamensis A. millsae

28. 
Regions with many geographic
barriers typically have more
species than do regions with fewer
barriers

29. 
 speciation takes place in geographically overlapping
populations
Sympatric speciation can also result from the
appearance of new ecological niches
For example, the North American maggot fly can live
on native hawthorn trees as well as more recently
introduced apple trees
 Sexual selection can drive sympatric speciation
Sympatric Speciation

30. 
Sexual selection for mates of different colors has
likely contributed to speciation in cichlid fish in Lake
Victoria
Normal Light Monochromatic orange light
P. pundamilia
P. nyererei

31. 
 In allopatric speciation, geographic isolation restricts
gene flow between populations
 Reproductive isolation may then arise by natural
selection, genetic drift, or sexual selection in the
isolated populations
 Even if contact is restored between populations,
interbreeding is prevented
 Sympatric speciation can result from polyploidy,
natural selection, or sexual selection

32. 
In sympatric speciation, a
reproductive barrier isolates a
subset of a population without
geographic separation from the
parent species

33. 
Microevolution happens on a small
scale, while macroevolution happens
on a scale that transcends the
boundaries of a single species. Despite
their differences, evolution at both of
these level relies on the same
established mechanisms of
evolutionary change

34. 
 http://www.occc.edu/biologylabs/documents/Biol
ogy/macroevolution.ppt
 http://www.uvm.edu/-
cmehrten/courses/earthist/evolution%20111.ppt
 http://evolution.berkeley.edu
 http://www.researchgate.net
 http://www.academia.edu
References