EVOLUTION

4.Darwin was surprised by the species he found on the Galapagos Islands.

 a) What other species did they remind him of?

 

The species Darwin saw on the Galapagos Islands reminded him of the animals he saw on South America.

 

b) What is the connection between the types of native animals on the Galapagos and their ability to cross the open ocean?

Darwin found that there wasn’t a single amphibian or large mammal on the island. This was particularly interesting because that would mean only animals that could travel the length of the ocean would be able to inhabit the Galapagos. Only native animals on the Galapagos were animals that could travel the distance which included birds, insects, plants, and reptiles.

 

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3. Use one or two examples to explain what Darwin meant by the term "selection".

 

When Darwin said selection, he meant that nature favours certain species reproductive success over another. Meaning nature picks certain individuals to reproduce. This is because those individuals exhibit a favourable trait that allows them to be more fit than other individuals within the same species. An example of this are polar bears. When Grizzly Bears found their way to the Arctic, it was difficult for them to capture prey because their prey would be able to see them from a mile away. Their fur was brown and easy to see in the arctic. Eventually a Bear was created with white fur and this is when Natural Selection comes into play. The Arctic environment favoured the bear with white fur allowing it to hide from prey and capture it. This allowed the polar bear to reproduce and this is an example of both survival of the fittest and natural selection. The environment selected the polar bear and gave it reproductive success in the Arctic over Grizzly Bears.

 

4. A male walrus lives to be 20 years old and mates with 18 females during its life. A second male lives to be 10 years old but mates with 44 females. Which male has natural selection "favoured?" Explain your reasoning.

The 10 year old male is favoured. This is because natural selection favours the reproduction success of an individual. The 10 year old individual produced 44 females so although he died earlier his natural selection is still favoured and he is considered more fit over the other.

 

5. Suggest a probable selective advantage for each of the following traits:

a) Clear wings of many flying insects

The wings allow the insect to hide.

b) Long tongue of a chameleon

The chameleon will be able to grab things at a further distance

c) Tendrils of climbing plants

Tendrils allow plants to get more sunshine

d) Eel's body shape

Allows the eel to swim better and allows it to slither and move around objects

e) Dramatic coloration of the non-venomous false coral snake

Tricks other people into thinking the snake is venomous