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History of Life and the Origin of Species. Mrs. Stewart Honors biology Central Magnet School. Standards:. CCSS ELA 9-10.2 I can trace the historical development of the theory of evolution I can summarize the evidence for the theory of evolution CCSS ELA 9-10.8 - PowerPoint PPT Presentation
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History of Life and the Origin of SpeciesMrs. StewartHonors biologyCentral Magnet School
Standards:CCSS ELA 9-10.2
I can trace the historical development of the theory of evolution
I can summarize the evidence for the theory of evolution
CCSS ELA 9-10.8I can critique and evaluate competing
evolutionary arguments based on scientific knowledge, empirical evidence and logical arguments regarding relevant factors.
Objectives (today, I will…)
Differentiate between spontaneous generation and biogenesis
Differentiate between Charles Darwin and Jean-Baptiste Lamarck
Choose…
But choose wisely.
Decide which partner is the bird and which is the cat.
History of Life
Biogenesis:All living things come from other
living things
Spontaneous Generation:Living things could arise from
nonliving things
Redi’s experiment
Previous idea: Flies were created from rotten meat
Redi: Meat kept away from adult flies would not produce maggots
Spallanzani & Pasteur
Spallanzani – tried to disprove that microorganisms arose from a “vital force” in the air
Pasteur – improved spallanzani’s experiment to eliminate the flaw of “no air”
Cats
Tell your bird how Pasteur improved upon Spallanzani’s experiment to disprove spontaneous generation
EndosymbiosisWhere/how did mitochondria get their own
DNA?How did chloroplasts become so specialized?Theory of Endosymbiosis:
Aerobic prokaryotes were engulfed by eukaryotic cells evolved into mitochondria (which perform aerobic respiration)
Photosynthetic prokaryotes were engulfed by plant cells and evolved into chloroplasts (where photosynthesis occurs)
Ch. 15.1 – 15.2
History of Evolution
Mrs. StewartHonors BiologyCentral Magnet School
What is Evolution?Dictionary:The gradual development/change of
something; especially from a simple to complex form.
Text book: (In biology) Generally, the process of change
by which new species develop from pre-existing species over time
Evolution of Dance
Birds
Tell your cat what Evolution means. Give an example (not one that Mrs. Stewart used)
18th Century IdeasAbout living species:
About the Earth:
Uniformitarianism
All species were permanent and unchanging.
Earth was only a few thousand years old and unchanging.
Idea by Charles Lyell that said geologic processes happed slowly over time and that some features of the Earth may take millions of years to form.
19th Century Ideas
Cats
Give your bird an example to support Lyell’s theory.
Jean-Baptiste Lamarck
French Naturalist1809 Lamarck’s Hypothesis: by selective use or
disuse of organs, organisms acquire or lose certain traits. These traits could then be passed on to their offspring.
Lamarck believed over time, this process led to change in a species.
Lamarck’s Hypothesis
1. Tendency toward perfection - All organisms have an innate tendency toward complexity and perfection, so they are continually changing to be more successful in their environment2. Use and disuse - Organisms can alter their bodies/organs by use or disuse 3. Inheritance of acquired traits - Organisms can pass on those altered body parts/organs to the offspring
Birds
What did Lamarck get right?
Cats
What did Lamarck get wrong?
Lamarck the Loser
First to develop a hypothesis of evolution
First to realize organisms adapt to their environment
But, Behavior has no effect on inheritable characteristics
Ch. 15.1 – 15.2
History of Evolution
Mrs. StewartHonors BiologyCentral Magnet School
Charles Darwin1809 – 1882Naturalist – study of nature
and the natural worldSailed on the HMS Beagle
in 1831Every time the ship
docked, Darwin went ashore to collect plant and animal specimens
Darwin’s observations piqued his interest in the diversity of life he observed.
Darwin even found evidence that suggested species once present on earth had vanished.
Researchers today speculate that 99.9% of all species that ever inhabited earth are now extinct.
Galapagos IslandsThe islands were close together, but had
very different climatesSmallest and lowest islands = hot, dry &
barrenHood Island = sparse vegetation
Higher islands had greater rainfall and a different assortment of plants/animalsIsabella Island = rich vegetation
Land Tortoise shell shapes could be used to identify which island it inhabited
What observations can YOU make about these species of land tortoise?
Pinta Island Tortoise
Isabella Island Tortoise
Hood Island Tortoise
What predictions can YOU make about the island environment for each tortoise?
Which island would you predict has only low-lying vegetation?
Pinta Island Tortoise
Isabella Island Tortoise
Hood Island Tortoise
Darwin’s Idea
Darwin observed that the plants and animals varied noticeably among the different Galapagos Islands.
However, Darwin wondered if animals living on different islands had once been members of the same species – originating from the same South American ancestor
Darwin’s FinchesDarwin observed many different types
of “finch” and noticed several different beak shapes.
Why?He began to notice different shaped
beaks were “adaptations” for different food sources
Religion’s RoleDarwin was a devout Catholic
He knew that his ideas, based on what he observed would provoke the catholic church
He debated over what to do for 25 years.
Darwin’s Theory –Descent With Modification
The Origin of Species by Means of Natural Selection – 1858
Every species – living or extinct – descended by reproduction from preexisting species
ANDSpecies must be able to change over
time
Natural Selection Mrs. StewartHonors biologyCentral Magnet School
Review
What was Lamarck’s hypothesis?
What did Darwin believe?
Inheritance of acquired traits
Species changed as environment changed – adaptation and survival of the fittest
Standards:CCSS ELA 9-10.2
I can trace the historical development of the theory of evolution
I can summarize the evidence for the theory of evolution
CCSS ELA 9-10.8I can critique and evaluate competing
evolutionary arguments based on scientific knowledge, empirical evidence and logical arguments regarding relevant factors.
Objective (Today I will…)
Explain the idea of “natural selection” and determine “fittest”
Examine how adaptations help animals survive better
Darwin’s reasoning for Natural Selection
1. Overproduction – more offspring are produced than can survive due to competition for resources
2. Genetic Variation – within a population, individuals have different traits. New traits may appear spontaneously.
3. Struggle to survive – constant competition may cause some variations/traits to be advantageous
4. Differential Reproduction – Organisms with the best adaptations will survive and reproduce, thus the advantageous adaptations will become most prevalent in the population.
Evolution by Natural Selection
Struggle for existence – each member of a species competes regularly for food, living space and other necessities of life. main needs: Food, water, living
space and ability to reproduceWho wins?
Think – Pair – Share
How can we describe Natural Selection in just 4 words?
Survival of the FittestHow well suited an organism is to it’s
environmentDoes fittest mean strongest?Does fittest mean in the best shape?
Fitness – the ability of an individual to survive and reproduceThe result of adaptations
What determines fitness?
The Environment!
Fitness leads to evolution
Peppered moth virtual lab
Survival of the FittestFittest – the individuals most capable to survive
and reproduce for multiple generations
The traits selected as the most useful for survival and reproduction are determined by the organisms environment
Natural Selection accounts for Descent with Modification as species become better adapted to different environments.
BirdsExplain to your cat how the
environment can determine fitness – use a specific plant or animal as an example.
(Not one Mrs. Stewart gave you)
What is a Population?A group of organisms of the same
species, that live in the same area, AND that interbreed
Adaptation vs. Acclimatization
Adaptation - Changes in traits in populations over timeExample: White moth population
becoming a black moth population after 5 generations.
Acclimatization – individual organism changes physiologicallyExample: growing thicker fur in winter
AdaptationsAny inherited characteristic that increases an
organism’s (and therefore, a populations) ability to survive and reproduceAnatomical or structural characteristics
Porcupine quills - protectionLonger necks in giraffes – find food
Physiological processesHow a plant performs photosynthesis
Instinctual BehaviorsHunting in packsLiving in burrows
Can You…
Differentiate between biogenesis and spontaneous generation
Differentiate between Charles Darwin and Jean-Baptiste Lamarck
Explain the idea of “natural selection” and determine “fittest”
Evidence of EvolutionMrs. StewartHonors BiologyCentral Magnet School
Standards:
CLE 3210.5.3 – Explain how genetic variation in a population and changing environmental conditions are associated with adaptation and the emergence of new species.
Descent with Modification
Over long periods of time, natural selection produces organisms with different structures, niches or occupy different habitats than their ancestors.
Each living species has descended, with changes, from other species over time.Result: species today look/act different
from their ancestors
Common DescentLook back: Tigers, panthers and
cheetahs all share a common ancestorLook back further: you will find
ancestors that these cats share with horses, dogs and bats.
Farther back: common ancestors of mammals, birds, alligators and fishes.
Logic: looking far enough back we should find the common ancestor for all living things
Common Descent
Evidence of
Evolution
Fossil Records
Homologous & Analogous Structures
Molecular Biology
Comparative Embryology
Vestigial Structures
Fossil Records
Compare fossils from older layers and younger layers and show changes in species over time
Fossils - preserved remains of ancient organisms
Fossil Records
Compare fossils found around the world and we can infer when and where different organisms existed.
Fossils also provide evidence about the environment in which the organism existed and for which the organism adapted
Transitional Species
Fossil records show species which have features that are intermediate between those of hypothesized ancestors and later descendant species
Homologous vs. Analogous Structures
Homologous – refers to structures that share the same basic structure but may differ greatly in function
Analogous – refers to structures that vary
greatly in structure but may share the same function
Homologous Body
Structures
Homologous Body Structures
The limbs of reptiles, birds and mammals (arms, wings, legs and flippers) vary greatly in function but are all constructed from the same basic bones.
Anal
ogou
s St
ruct
ures
Drag picture to placeholder or click icon to add
Vestigial Structures
organs/body parts that were once used, but by natural or artificial selection, are no longer necessary
Vestigial OrgansAp
pend
ix
Vestigial Organs
Hip bone in a whale
Vestigial OrgansTa
ilbon
e in
hum
ans
Vestigial Organs
Plica Luminaris = Third Eyelid
Similarities in Embryology
The early stages, or embryos, of many animals with backbones are very similar.
Does this mean that a human embryo is ever identical to a fish, or a bird embryo?
NOBut, many embryos look especially
similar during early stages of development.
Fish Salamander Tortoise ChickenPig Man
Comparative Embryology
What do these similarities mean?
The same groups of embryonic cells develop in the same order and in similar patterns to produce the tissues and organs of all vertebrates.
All animals go through this process
Its at the blastocoel step that we differ Blastopore
could become mouth or anus, etc.
Molecular Biology
Using new technology, we can see how many DNA and RNA sequences organisms share in common
Amino acid sequences used to determine how closely related different species are.
The number of amino acids that differ from human hemoglobin
Molecular BiologyAmino Acid Similarities
Which two plants are the most closely related according to this chart?
Assignment:
Evidence of evolution dry lab activity packet
Exit Ticket: Socrative.comRoom Number: Stewart 348
Question: How does the environment determine the “fittest” individual?