Bellwork: 02/13/2012
Collect the following data:
 Chlorine
Salt Water Tanks Only:
 DO
- Phosphate
 Turbidity
- Salinity
 Nitrate
- Calcium
 Nitrite
- Water Hardness
Make sure to clean out any excess
 Ammonia
food
 pH
from your filter and gravel/sand.
 Temperature Scrub off
(Fresh water only)
the inside of the glass & clean the
outside
with Windex once you are finished.
Evolution and Biodiversity
Before we start:
What is a scientific theory?
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It makes falsifiable predictions with consistent accuracy
across a broad area of scientific inquiry
It is well-supported by many independent strands of
evidence, rather than a single foundation
It is consistent with pre-existing theories and other
experimental results
It can be adapted and modified to account for new evidence
as it is discovered, thus increasing its predictive capability
over time.
It is among the most parsimonious explanations, sparing in
proposed entities or explanations.
Other Scientific Theories:
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The Atomic Theory
Theory of Matter and Energy
Theory of Plate Tectonics
Theory of Quantum Mechanics
Theory of of Molecular Bonds
Theory of the States of Matter
Theory of Homeostasis
Theory of Gravity
Theory of Evolution (we are the only Westernize
country that argues about this)
Keep In Mind:
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The theory of evolution and:
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Creationism
Neo-creationism
Intelligent design
Creation science (“science”)
Are not equal on an intellectual and rational level
Evolution: All species
descended from earlier
ancestral species.
Changing genetic makeup in a population over
time.
Accepted scientific
explanation of how
animals adapt and
survive
Evolution and Adaptation
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Macroevolution – long term, large scale
changes; one species turns into a different
species
Microevolution – small genetic changes;
changes within a species
Gene pool – all genes in a population
Mutation – random change in structure of
DNA. Every so often, a mutation is beneficial
for survival.
Natural selection – individuals that have traits
that benefit survival.
Natural Selection
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Microevolution is changes in the gene pool
of a population over time that result in
changes to the varieties of individuals in a
population such as a change in a species'
coloring or size.
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Macroevolution If the changes are over a
very long time and are large enough that the
population is no longer able to breed with
other populations of the original species, it is
considered a different species.
Evolution and Adaptation
Microevolution
Macroevolution
Natural Selection
Three things must happen:
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1. Genetic variability in a trait within
population
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2. Trait is heritable
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3. Differential reproduction – must enable
individuals with the trait to leave more
offspring than others without the trait.
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Adaptive (heritable) trait helps survival and
reproduction under current conditions
Speciation, Extinction, and
Biodiversity
How Species Evolve
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Speciation
Geographic isolation
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Reproductive isolation
Fig. 5-7 p. 94
Extinction
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When Environmental changes occur, species must evolve to adapt.
If not…
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Background extinction – slow rate
Mass extinction – quickly, large groups
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99% of species that have existed on earth are now extinct.
Changes in Earth’s biodiversity – has leveled off during the last
1.8 million years. Is this due to human influence?
Extinction
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Adaptive radiation – after mass extinctions,
numerous new species evolve to fill vacated
niches. Takes 1-10 million years for adaptive
radiation to rebuild biodiversity.
Human impacts – accelerated extinction
Human Impacts on Evolution
Artificial Selection – artificially selecting superior
genetic traits
• Agriculture
• Hatcheries
• pets
Genetic Engineering
• Gene splicing
• Species creation in laboratories
• Takes less time than artificial selection
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http://en.wikipedia.org/wiki/Image:Geologica_time_USGS.png
Evolution: Periods of the
Earth
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The age of the Earth is difficult to determine
with absolute certainty
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It is thought to be about 4.57 billion years old
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This age is based on
dating of both the oldest
terrestrial minerals on
Earth and of meteorite
and lunar samples,
which provide estimates
of the age of the solar
system
http://en.wikipedia.org/wiki/Image:Asaphiscuswheelerii.jpg
How old is the Earth?
• This estimate is based on a
combination of radiometric dating of
the oldest terrestrial minerals on the
planet (small crystals of zircon found
in western Australia), and estimates
by astronomers of the age of the
solar system, based on radiometric
dating of meteorite and lunar
samples.
• The Earth is believed to have formed
early on in the formation of the solar
system.
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Technique known as radiometric dating
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Rocks are made up of chemical elements
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These elements decay at a constant rate over
time into radioactive
isotopes
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The ratio of
radioactive to nonradioactive isotopes
provides an
estimate of age
http://en.wikipedia.org/wiki/Image:DirkvdM_rocks.jpg
How do we Age Rocks?
•All matter, including rocks, is made up of chemical
elements. When a rock is first crystallized, it
contains elements in their “normal” state or
isotope.
• However, over time, changes take place in the
elements that make up the rock, and radio-active
isotopes begin to accumulate in the rock at a
constant rate of disintegration.
• These radioactive products remain in the rock
along with what is left of the original material. The
ratio of radioactive to non-radioactive isotopes give
us a gauge as to the age of the rock.
• Uranium was one of the first elements used in
radiometric dating. Argon and potassium are now
usually used.
Geological Time Scale
Eon is the largest sub-division of geological time
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First three eons (Hadean, Archean, Proterzoic)
are collectively known as the Precambrian eon
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Eons are sub-divided into eras
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Eras are sub-divided into periods
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Periods are sub-divided into epochs
http://en.wikipedia.org/wiki/Eon_%28geology%29
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Paleozoic (543 to 250 million
years ago), divided into six
periods
CENO
-ZOIC
Phanerozoic eon is divided into
three eras:
Cretaceous
65
MYA
Jurassic
Permian
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Mesozoic (250 to 65 million
years ago), divided into three
periods
Cenozoic (65 million years
ago to present), divided into
two periods and seven
epochs
Present
Tertiary
Triassic
PALEOZOIC
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Quaternary
MESOZOIC
Phanerozoic Eon – Ancient Life
250
MYA
Carboniferous
Devonian
Silurian
Ordovidan
Cambrian
543
MYA
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542 to 488 Million years ago
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Sudden appearance in the fossil record of many new
phyla (Cambrian explosion)
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Fauna included:
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Earliest animals with a notochord (Pikaia spp.)
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Abundant marine invertebrates
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Primitive marine algae
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Brachiopods
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Arthropods
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Echinoderms
Pikaia gracilens
http://park.org/Canada/Museum/burgessshale/NK20.GIF
Cambrian Period
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488 to 444 Million years ago
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Diversity of marine invertebrates, including molluscs,
coelenterates, graptolites, trilobites, euryptids
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Earliest vertebrates appeared (ostracoderms)
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The first plants
invaded land
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A major extinction
event in which 60%
of marine species
were wiped out
ended the
Ordovician period
http://en.wikipedia.org/wiki/Image:Ordovician_Sea.jpg
Ordovician Period
http://universe-review.ca/I10-29-placoderm.jpg
Silurian Period
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443 to 416 Million
years ago
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Coral reefs became
abundant
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First jawed fish
appeared
(Placoderms)
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First freshwater
fish appeared
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First vascular plants appeared on land
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Myriapods (a type of arthropod) became the first animals
to colonise land
Placoderm
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416 to 360 Million years ago
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First fish evolved into tetrapods and invaded land
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Cartilaginous fish (sharks) became dominant
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Trees and forests colonized the land
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Terrestrial invertebrates
invaded the land
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Another major extinction
of marine fauna ended
the Devonian period
http://universe-review.ca/I10-72-Eusthenopteron.jpg
Devonian Period – “age of the
fish”
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360 to 299 Million
years ago
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Climate became drier
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The first conifers
appeared
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Extensive forests
appeared with prolific
insect life, including
the first winged insects
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The first reptiles evolved from amphibians
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The first ammonites evolved
http://universe-review.ca/I10-68-Carboniferous.jpg
Carboniferous Period
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299 to 250 Million years ago
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Major transition in vegetation
from ferns to more advanced
conifers and ginkgo trees
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Deserts were established
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Amphibians became larger in size
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Insects continued to radiate, with the appearance of
Coleoptera (beetles) and Diptera (flies)
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Reptiles thrived and began their radiation
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Ended with the largest extinction event on record – 96%
of animal species disappeared
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This also marked the end of the Paleozoic era
http://www.copyrightexpired.com/earlyimage/prehistoriclifebeforekt/dimetrodon.jpg
Permian Period
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250 to 200 Million years ago
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Conifers continued to expand
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Ammonites recovered from
their near extinction to
co-dominate the seas with
bony fish
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Reptiles returned to the seas
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The ancestors of snakes and
lizards evolved
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Beginning of the radiation of dinosaurs
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End of the Triassic marked with another extinction event
http://universe-review.ca/I10-33-Triassic1.jpg
Triassic Period
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200 to 145 Million years ago
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Warm climate and high sea
levels
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Cone-bearing plants covered
the land
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First small mammals
appeared
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First evidence of feathered
birds (Archaeopteryx)
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In addition to land and water,
reptiles also radiated into the
air (pterosaurs)
http://en.wikipedia.org/wiki/Image:SArchaeopteryxBerlin2.jpg
Jurassic Period
Archaeopteryx
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145 to 65 Million years ago
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Continents began to move into
their present-day positions
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First flowering plants appeared
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Mammals evolved into three
forms (monotreme, marsupial,
placental)
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A meteorite impact caused a
major extinction, which ended
the Cretaceous period – all
dinosaurs and all ammonites,
along with many other species,
became extinct
http://universe-review.ca/I10-68-flowering.jpg
Cretaceous Period
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65 to 1.8 Million years ago
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Paleocene epoch: flowering
plants became abundant
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Eocene epoch: many orders
of mammals appeared
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Oligocene epoch: primitive
apes; first elephants
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Miocene epoch: kelp forests
and grasslands appeared,
many grazing animals
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Pliocene epoch: First ancient
hominids arose
http://universe-review.ca/I10-36-oldesthominid.jpg
Tertiary Period
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1.8 Million years ago to present
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Pleistocene epoch: modern humans evolved; ended with
the Ice Age that saw the extinction of mammoths and
other animals
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Holocene epoch: human civilization spread throughout
the globe and humans became the dominant form of life
http://universe-review.ca/I10-37-Quaternary.jpg
http://www.primates.com/homo/homo-sapiens.jpg
Quaternary Period
In a group of 2 or 3:
Imagine a species that came into being during the
Cambrian Explosion and some form of this
species survived through all eras to our modern
time.
Draw and describe your species and adaptations
through each period (11 total)
Each Period should have:
a drawing
a description of how it survives
a description of a new adaptation for the
changed environment (land, water, temperature,
predators, etc)
Bellwork
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Look over your vocabulary before the quiz