Transcript Physical traits * Alike or Different?

Specialized Structures
Vocabulary Review
Trait
Vocabulary Review
• Trait – A characteristic
Variation
Variation
• Differences in appearance of an inherited trait
among members of a species.
Why is variation important?
Why is variation important?
• It gives a species (group of plants or animals) a
better chance to live, or a survival advantage.
Charles Darwin – Natural selection
• Survival of the fittest
The Voyage of HMS Beagle
Traits and Survival
Environmentally Influenced Traits
Camouflage
• Allows the prey to hide
• Confuses the predator
• Helps Predators Sneak up
on Prey
Camouflage:
• The ability to blend in with
its environment because of
its inherited traits.
What is hiding in here?
How about here?
And the last one…
Antarctic toothfishAntifreeze Fish
What on earth?
• Toothfish can survive in
freezing waters
• Large, deep sea predatory
fish found only in
Antarctica.
• Contain special proteins
that act like anti-freeze
• Commercial Fishermen
started overfishing after
the Patagonian toothfish
was depleted.
Special Qualities of the toothfish
• https://www.youtube.c
om/watch?v=OEIMuncbts
Natural Selection vs. Adaptation
• Natural Selection:
• Inherited Traits change
over time from
generation to generation
Occurs when:
1. There is variation in the
traits of organisms
within ia species.
2. The traits give
individuals an advantage
over others in surviving
3. The individuals will be
likely to have more
offspring.
SNOWSHOE HARES
Hare in summer
Hare in winter
Cite examples of genetic traits in
organism due to natural influences.
“Survival of the fittest”
• Natural selection is the
process by which traits
become either more or less
common in a population.
“hide me!”
Genetic trains in organisms due to
manmade influences.
Peppered Moth
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Dark colored peppermoths were rare
before 1811. The light colored moths
were seen all over England.
During the Industrial Revolution, when
coal was used, the city was blanketed in
dark soot. The white moths were seen
more readily, and the dark colored
moths started to show up more often.
Soon, the light colored moths were
almost gone, and the dark had taken
over. It was a result of camouflage in a
clean environment vs. camougflage in a
dirty environment.
The moths are now known as the best
example of Darwin’s evolution.
Dodo Bird
Not as dumb as you might think
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Dodo birds lived on the island of Mauritis
near Madagascar. They were discovered in
1507 by the Portuguese, and in only 174
years became extinct. Contemporary
accounts claim that men brought as many as
50 large birds on board their ship a day, and
often about half were dodoes.4
Although scientists once believed the birds
died because of lack of intelligence, this has
been disproved.
Dodoes only laid one egg at a time. When
explorers came to the island the rats, pigs,
and monkeys which arrived with the sailors
and pillaged the dodo’s vulnerable ground
nests.
Dodoes did not need to fly because they had
abundant food on the island. This made
them easy prey for the sailors to catch and
eat.
Bristlecone Pine (high altitude)
• Grow up near the
treeline
• Smaller phloem and
xylem help water reach
the top
• Grow Slowly
• Live a long time
• Spread out
Owls
Owls
• Owls are nocturnal
(awake at night) – have
large eyes to see
• Serrated feathers on
wingtips help them fly
silently
• Sharp beaks and talons
help it catch prey
Hummingbird
Hummingbirds
• Drink nectar from
flowers
• Wings help them hover
in midair
• Can fly backwards
• Long tongue to help get
nectar
Specialized Structures
Some traits that allow an organism to survive in
one environment but not another. These
traits are often referred to as Specialized
Structures.
Desert Cactus
Check out these feet? Why are they so
different?
Snowshoe Hare
Cottontail Rabbit
Bristlecone Pine
Temperature Control
Keeps a warm layer close to the
body. What else controls a polar
bear’s temperature?
Sweat glands help keep the body
cool. What is latherin?
Orchids in the rainforest
• Grow in rainforests
• Require warm and wet
climate
• Open in morning and
close at noon
• Scent attracts bees,
birds, and butterflies
• Large leafs help with
photosynthesis
Desert cactus
• The desert cactus does
not receive water.
• Spines keep away
predators
• Wax keeps water in
• Roots grow when it
rains then die again
• Water is stored in plant
The evolution of Bugs Bunny
Crocodiles – WHY?
The American alligator
(commonly found in the
Florida Everglades)
Tough skin, sharp jaws,and
A lack of natural predators
Have kept this creature
Alive for millions of years.
Elephant Seals
Ano Nuevo State Park – CA: In November, the male elephant seals start arriving on
shore and fighting. Those that win all the fights are crowned alpha bulls. The alpha bulls
rule harems of around 50 female elephant seals. The truly vanquished males retreat to
what is now known as "Losers' Beach." The beaten “sneaker bulls” loiter on the fringes of
the harems hoping to find an unattended female on the edge of the harem.
Defense against predators
Scales
Shells
That’s All, Folks!