Download how populations evolve

EVOLUTION
HOW
POPULATIONS
EVOLVE
KRAUZ
BIOLOGY (H)
HOW POPULATIONS
EVOLVE
FOR A LONG TIME IT WAS
BELIEVED THAT THE EARTH
WAS ONLY 6,000 YRS OLD
IT WASN’T UNTIL THE 1800’S
THAT SCIENTISTS
SUGGESTED EARTH IS OLDER
AND THAT LIFE EVOLVES!!
HOW POPULATIONS
EVOLVE
LAMARCK
PROPOSED ONE
THEORY ON HOW
EVOLUTION
OCCURS
USE AND DISUSE
(ACQUIRED
CHARACTERISTICS)
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
ACQUIRED
CHARACTERISTICS
ORGANISMS MAY
DEVELOP TRAITS
DURING THEIR
LIFETIME THAT
CAN BE PASSED
ON TO THEIR
OFFSPRING
HOW POPULATIONS
EVOLVE
DARWIN
PROPOSED
ANOTHER
THEORY OF
EVOLUTION
DESCENT WITH
MODIFICATION
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
DARWIN COLLECTED DATA FROM
AROUND THE WORLD!!
HOW POPULATIONS
EVOLVE
DARWIN’S
STUDIES LED
HIM TO
PUBLISH “THE
ORIGIN OF
SPECIES BY
THE MEANS OF
NATURAL
SELECTION”
HOW POPULATIONS
EVOLVE
DESCENT WITH MODIFICATION
ALL ORGANISMS RELATED THROUGH
DESCENT FROM AN UNKNOWN SPECIES
THAT LIVED IN THE PAST
AS TIME PASSED, ADAPTATIONS
WERE DEVELOPED WITHIN A
SPECIFIC SPECIES THAT WERE
PASSSED ON TO FUTURE
GENERATIONS
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
THERE ARE
FIVE MAJOR
SOURCES OF
EVIDENCE FOR
EVOLUTION
FOSSILS
BIOGEOGRAPHY
COMPARATIVE
ANATOMY
COMPARATIVE
EMBRYOLOGY
MOLECULAR
BIOLOGY
HOW POPULATIONS
EVOLVE
FOSSILS
THE IMPRINTS
OR REMNANTS
OF
ORGANISMS
THAT LIVED
IN THE PAST
HOW POPULATIONS
EVOLVE
THE FOSSIL RECORD AND
RADIOACTIVE DATING GIVE
US A TIMELINE FOR LIFE
THE OLDEST KNOWN FOSSIL
IS ABOUT 3.5 BILLION YEARS
OLD
HOW POPULATIONS
EVOLVE
FOSSILS SUGGEST WHALES
EVOLVED FROM LAND MAMMALS
WITH 4 LEGS
HOW POPULATIONS
EVOLVE
BIOGEOGRAPHY
GEOGRAPHIC
DISTRIBUTION
OF SPECIES
ORGANISMS
APPEAR MORE
SIMILAR TO
ORGANISMS
FROM THE
SAME AREA
HOW POPULATIONS
EVOLVE
COMPARATIVE ANATOMY
HOW POPULATIONS
EVOLVE
COMPARATIVE
ANATOMY
THE
COMPARISON
OF BODY
STRUCTURES
IN DIFFERENT
SPECIES
HOW POPULATIONS
EVOLVE
 HOMOLOGOUS
STRUCTURES
 FEATURES THAT
OFTEN HAVE
DIFFERENT
FUNCTIONS BUT
ARE
STRUCTURALLY
SIMILAR
BECAUSE OF
COMMON
ANCESTRY
HOW POPULATIONS
EVOLVE
COMPARATIVE EMBRYOLOGY
HOW POPULATIONS
EVOLVE
 COMPARATIVE
EMBRYOLOGY
 THE STUDY OF
STRUCTURES
THAT APPEAR
DURING THE
DEVELOPMENT
OF DIFFERENT
ORGANISMS
PHARYNGEAL
SLITS ARE
PRESENT IN
ALL
VERTEBRATES
(FISHES,
FROGS,
SNAKES,
BIRDS, APES)
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
 MOLECULAR
BIOLOGY
 THE STUDY OF
THE MOLECULAR
BASIS OF GENE
AND GENE
EXPRESSION
 RELATED
INDIVIDUALS
HAVE A GREAT
AMOUNT OF
SIMILAR DNA
HOW POPULATIONS
EVOLVE
DARWIN PROPOSED NATURAL
SELECTION AS THE MECHANISM
FOR EVOLUTION
HOW POPULATIONS
EVOLVE
HOW DOES
NATURAL
SELECTION
WORK?
 OVERPRODUCTION
 LIMITED
RESOURCES
(COMPETITION)
 HERITABLE
VARIATIONS
 NATURAL
SELECTION
(“SURVIVAL OF THE
FITTEST”)
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
ARTIFICIAL
SELECTION
SELECTIVE
BREEDING OF
DOMESTICATED
PLANTS AND
ANIMALS
HOW POPULATIONS
EVOLVE
TWO MAIN FEATURES OF
DARWIN
DESCENT WITH MODIFICATION
NATURAL SELECTION
HOW POPULATIONS
EVOLVE
SCIENTISTS
CAN OBSERVE
NATURAL
SELECTION IN
ACTION
INSECTICIDE
SPRAYING
(DDT) VS
EFFECTIVENESS
INDUSTRIAL
REVOLUTION
PEPPERED
MOTH COLOR
HOW POPULATIONS
EVOLVE
POPULATIONS ARE THE
UNITS OF EVOLUTION, BUT
WHAT IS A POPULATION?
HOW POPULATIONS
EVOLVE
POPULATION
??
HOW POPULATIONS
EVOLVE
POPULATION
A GROUP OF INDIVIDUALS OF THE
SAME SPECIES LIVING IN THE
SAME PLACE AT THE SAME TIME
SPECIES
A GROUP OF POPULATIONS WHOSE
INDIVIDUAL HAVE THE
POTENTIAL TO INTERBREED AND
PRODUCE FERTILE OFFSPRING
HOW POPULATIONS
EVOLVE
 DARWIN COULD
NOT EXPLAIN
THE GENETIC
BASIS OF
POPULATION
CHANGE (I.E.
VARIATION)
 POPULATION
GENETICS
 THE SCIENCE OF
GENETIC
CHANGE IN
POPULATIONS
HOW POPULATIONS
EVOLVE
MICROEVOLUTION
CHANGE IN A
POPULATIONS
GENE POOL OVER
TIME
GENE POOL
THE TOTAL
COLLECTION OF
GENES IN A
POPULATION AT
ANY ONE TIME
HOW POPULATIONS
EVOLVE
THE GENE
POOL OF A
NONEVOLVING
POPULATION
WILL REMAIN
CONSTANT
OVER
GENERATIONS
HARDY-WEINBERG
EQUILIBRIUM
THE FREQUENCY OF
EACH ALLELE IN THE
GENE POOL WILL
REMAIN CONSTANT
UNLESS ACTED ON BY
AN OUTSIDE AGENT
HOW POPULATIONS
EVOLVE
IF A GENE POOL ISN’T CHANGING,
WE CAN CALCULATE THE
FREQUENCY OF ALLELES
HOW POPULATIONS
EVOLVE
HARDY-WEINBERG
FORMULAS
P + Q = 1
P2 + 2(P)(Q) + Q2 = 1
HOW POPULATIONS
EVOLVE
FIVE
CONDITIONS
MUST BE MET
IN ORDER FOR
HARDYWEINBERG
EQUILIBRIUM
TO HOLD
TRUE
 LARGE
POPULATION
 NO MIGRATION /
IMMIGRATION
 NO MUTATION
 RANDOM MATING
 ALL INDIVIDUALS
EQUAL CHANCE
OF
REPRODUCTIVE
SUCCESS
HOW POPULATIONS
EVOLVE
SINCE HARDY-WEINBERG
CONDITIONS CAN NOT BE MET IN
THE WILD, MICROEVOLUTION
WILL OCCUR
FOUR MAJOR CAUSES OF
MICROEVOLUTION
GENETIC DRIFT
GENE FLOW
MUTATION
NATURAL SELECTION
HOW POPULATIONS
EVOLVE
GENETIC DRIFT
HOW POPULATIONS
EVOLVE
GENETIC
DRIFT
A CHANGE IN
THE GENE
POOL IN A
SMALL
POPULATION
DUE TO
CHANCE
HOW POPULATIONS
EVOLVE
TWO COMMON
TYPES OF
GENETIC
DRIFT
BOTTLENECK
EFFECT
FOUNDER
EFFECT
HOW POPULATIOS
EVOLVE
GENE FLOW
FERTILE
INDIVIDUALS
MOVE INTO
OR OUT OF A
POPULATION,
OR WHEN
GAMETES ARE
TRANSFERRED
BETWEEN
POPULATIONS
MUTATIONS
A RANDOM
CHANGE IN AN
ORGANISM’S
DNA THAT
MAY CREAT A
NEW ALLELE
HOW POPULATIONS
EVOLVE
NATURAL SELECTION RESULTS IN
THE ACCUMULATION AND
MAINTENANCE OF TRAITS THAT
ADAPT A POPULATION TO ITS
ENVIRONMENT
SUMMARY OF CAUSES OF
MICROEVOLUTION
HOW POPULATIONS
EVOLVE
VARIATION IS EXTENSIVE IN MOST
POPULATIONS
POLYMORPHISM
TWO OR MORE FORMS OF A TRAIT IN NOTICEABLE
NUMBERS
HOW POPULATIONS
EVOLVE
CLINE
HOW POPULATIONS
EVOLVE
WHAT ARE
THE CAUSES
OF
VARIATION?
MUTATION AND
SEXUAL
RECOMBINATION
HOW POPULATIONS
EVOLVE
NATURAL
SELECTION
EFFECTS
VARIATION BY
FAVORING A
PARTICULAR
PHENOTYPE
HETEROZYGOTE
ADVANTAGE
HETEROZYGOTE
HAS GREATER
REPRODUCTIVE
SUCCESS
NEUTRAL
VARIATION
NO SELECTIVE
ADVANTAGE
HOW POPULATIONS
EVOLVE
THERE ARE
THREE
GENERAL
OUTCOMES OF
NATURAL
SELECTION
STABILIZING
SELECTION
DIRECTIONAL
SELECTION
DISRUPTIVE
SELECTION
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
STABILIZING SELECTION
CONDITIONS TEND TO REDUCE
PHENOTYPIC VARIATION
DIRECTIONAL SELECTION
SHIFTS THE OVERAL MAKEUP OF
THE POPULATION BY ACTING
AGAINST INDIVIDUALS AT ONE OF
THE PHENOTYPIC EXTREMES
DISRUPTIVE SELECTION
FAVORS INDIVIDUALS AT BOTH
EXTREMES OF THE PHENOTYPIC
RANGE
HOW POPULATIONS
EVOLVE
SEXUAL SELECTION MAY
CAUSE SEXUAL DIMORPHISMS
HOW POPULATIONS
EVOLVE
HOW POPULATIONS
EVOLVE
SEXUAL
DIMORPHISM
THE
DISTINCTION
OF
APPEARANCE
BETWEEN A
MALE AND
FEMALE OF
THE SAME
SPECIES
 INTRASEXUAL
SELECTION
 SAME SEX, SAME
SPECIES
COMPETE FOR
MATE
 INTERSEXUAL
SELECTION
 OPPOSITE SEX
GETS TO
CHOOSE MATE
HOW POPULATIONS
EVOLVE
TRAIT MAY HURT SURVIVAL, BUT
INCREASE REPRODUCTIVE
SUCCESS
HOW POPULATIONS
EVOLVE
EVOLUTION CAN NOT CREATE A
PERFECT SPECIES BECAUSE
ORGANISMS ARE LOCKED INTO
HISTORICAL CONSTRAINTS
ADAPTATIONS ARE OFTEN
COMPROMISES
NOT ALL EVOLUTION IS ADAPTIVE
EVOLUTION CAN ONLY EDIT
EXISTING VARIATION
HOW POPULATIONS
EVOLVE
HOW POPULATIOS
EVOLVE
THE END!!