Let's review...

The arctic fox eats a small rabbit called the arctic hare in the north pole. Over the past few years, the climate has become warmer and a new fox, called the red fox has started moving into the arctic fox's territory. What interaction would scientists expect to see between the arctic fox and the red fox?

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Scientists have observed birds and squirrels in Portland, Oregon interacting in the following way: Birds retrieve nuts from unstable branches and bring them to the ground. Squirrels will bite open the nuts and share them with the birds.

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1) A tick2) A monkey & a gorilla3) A small fish hiding in a big fish's shadow4) A flee5) Plover birds and alligators

Today we are going to finish reviewing for our 9 weeks test

Population growth

68.6%

Population growth!!!!

If something helps an organism, the population will increase in size

What are some things thatwould make a populationincrease?

If something hurts an organism, the population will decrease in size

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1) Hunters kill off a large number of deer

a. Will this help or hurt the deer?b. Will the population increase or

decrease?

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2) Spring comes early and there are lots of berries for birds to eat.

a. Will this help or hurt the birds?b. Will the population increase or

decrease?

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3) Polar bears eat seals. Polar bears have been dying because of climate change. What affect will this have on the seal population size?

a. Will this help or hurt the seals?b. Will the population increase or

decrease?

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4) Both the white wolf and the gray wolf eat deer. The gray wolf is faster and stronger than the white wolf. How would if affect the white wolf's population size if many gray wolves moved into the white wolf's territory and began competing with them for food?

Adaptations are traits that help organisms survive in their environments.

1) What are some traits this organism has?2) What are its adaptations?

Which organism has a beak that is adapted to eating: 1) rodents 2) fish 3) nuts & berries ?

Natural selection says that organisms with good traits live and organisms with bad traits die

Natural selection favors traits that help an organism survive

Which trait does natural selection favor?

a) a purple stingray or a gray stingrayb) a animal that runs fast or an animal that runs slowc) an organism with good eyesight or an organism with normal eyesight

Good traits increase in a population.

Bad traits decrease in a population.

Let's practice...

1) Otters spend most of their time in the water fishing. An otter is born without webbed feet. a) What do you expect will happen to the frequency of this trait in the next generation?

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2) A eagle is born with especially good eyesight.a) What do you expect would happen to the frequency of this trait in the next generation?

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3a) The midwestern plains receive a large amount of rainfall in the winter and a low amount in the summer. In the winter, the midwestern plains are lush and green. Two varieties of garter snakes exist in this area: the green morph and the brown morph.

Which organism would natural selection favor in the winter?

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3b) In the summer, as water dries up, the grass on the midwestern plains turns brown.

Which organism would natural selection favor in the summer?

Let's practice...

Let's practice...

1) The layer made of liquid metal2) The thickest layer of the earth3) The thinnest layer of the earth4) The layer made of solid metal5) The hottest layers of the earth