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Wednesday Homework - Allopatric and Sympatric Speciation

Last updated 11 months ago
26 questions
Allopatric speciation occurs when a species separates into two separate groups which are isolated from one another. A physical barrier, such as a mountain range or a waterway, makes it impossible for them to breed with one another. Each species develops differently based on the demands of their unique habitat or the genetic characteristics of the group that are passed on to offspring. When Arizona's Grand Canyon formed, squirrels and other small mammals that had once been part of a single population could no longer contact and reproduce with each other across this new geographic barrier. They could no longer interbreed. The squirrel population underwent allopatric speciation. Today, two separate squirrel species inhabit the north and south rims of the canyon. On the other hand, birds and other species that could easily cross this barrier continued to interbreed and were not divided into separate populations.
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Sympatric speciation is controversial. Some scientists don’t believe it exists. Sympatric speciation occurs when there are no physical barriers preventing any members of a species from mating with another, and all members are in close proximity to one another.

A new species, perhaps based on a different food source or characteristic, seems to develop spontaneously. The theory is that some individuals become dependent on certain aspects of an environment—such as shelter or food sources—while others do not.
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According to the first paragraph, does sympatric speciation occur in the same area or in a different area? Present evidence to show proof of your claim.

Sentence Starter: Sympatric speciation occurs (in the same/different area)... My evidence can be seen from paragraph 1 sentence ____ where it states "...".

A possible example of sympatric speciation is the apple maggot, an insect that lays its eggs inside the fruit of an apple, causing it to rot.

As the apple falls from the tree, the maggots dig in the ground before emerging as flies several months later. The apple maggot originally laid its eggs in the fruit of a relative of the apple—a fruit called a hawthorn.

After apples were introduced to North America in the 19th century, a type of maggot developed that only lays its eggs in apples. The original hawthorn species still only lays its eggs in hawthorns. The two types of maggots are not different species yet, but many scientists believe they are undergoing the process of sympatric speciation.
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Can two different species breed and have offspring

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What is a hybrid?

Sentence Starter: According to the video, a hybrid is...

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Hybrids like the zonkey (a cross between a donkey and a zebra) are sterile which means that that are infertile and...

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Speciation is the development of new _______ and it occurs when populations of individuals are _______ in some form or sort of way.

Word Bank:
trust
isolated
species
close
chimed
carried
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What are the two main types of speciation called?

Sentence Starter: The two main types of speciation are called...

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In allopatric speciation there is a _______ barrier that _______ the populations.

Word Bank:
gametic
sense
missense
separates
geographic
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Over time populations can develop significant ____________________ that prevent viable offspring from being produced even if the populations were brought together.

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In _______ speciation, different species develop in the same _______. There is something else other than geography that is _______ the species.

Word bank:
mutation
area
resources
energy
sympatric
alliotopuc
isolating
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A prezygotic barrier...

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The Eastern and Western Meadowlark are an example of behavioral isolation (a prezygotic barrier) where two species do not produce a zygote. Why is this?

Sentence Starter: According to the video the Western and Eastern meadowlark are examples of behavioral isolation because..

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What are some examples of temporal isolation?

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In _______ isolation, _______ and fertilization still occur because there is a living _______. But there is some _______ that separates the species even still.

Word Bank:
restful
zygote
size
mating
barrier
dating
postzygotic
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The Zonkey hybrid (Zebra + Donkey) is a an example of a postzygotic barrier because...

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Sometimes offspring produced after mating...

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Does variety or different types of genetic traits, naturally exist in populations?

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Genes that produce high fitness (ability to survive and reproduce)...