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The Making of the Fittest: Evolving Switches, Evolving Bodies

15 minutes 26 seconds

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Still image from The Making of the Fittest: Evolving Switches, Evolving Bodies

After the end of the last ice age 10,000 years ago, populations of marine stickleback fish became stranded in freshwater lakes dotted throughout the Northern Hemisphere in places of natural beauty like Alaska and British Columbia. These little fish have adapted and thrive, living permanently in a freshwater environment drastically different than the ocean. Stickleback bodies have undergone a dramatic transformation, some populations completely losing long projecting body spines that defend them from large predators. Various scientists, including David Kingsley and Michael Bell, have studied living populations of threespine sticklebacks, identified key genes and genetic switches in the evolution of body transformation, and even documented the evolutionary change over thousands of years by studying a remarkable fossil record from the site of an ancient lake ten million years ago.

Media Details

Runtime: 15 minutes 26 seconds

Graphic of a strand of DNA with the C-G-A-T protein sequences. Caption: A mutation is a change in the chemical letters
The Making Of The Fittest
Episode 1
10 minutes 24 seconds
Grade Level: 10 - 12
Close up of a small, spiny, translucent fish. Caption: The fish absorb enough oxygen from the sea
The Making Of The Fittest
Episode 2
13 minutes 10 seconds
Grade Level: 10 - 12
Magnified view of red, spherical objects. Caption: Then he tested for the sickle cell character.
The Making Of The Fittest
Episode 3
14 minutes 3 seconds
Grade Level: 10 - 12
Two almost identical fish. One is larger and has an extra fin on the bottom of its body. Below each fish is a strand of DNA with the same section highlighted. Caption: changes in form are ultimately due to changes in genes.
The Making Of The Fittest
Episode 4
15 minutes 26 seconds
Grade Level: 10 - 12
People wrapped in cloth holding walking sticks, herding a large herd of bovine. Caption: people started domesticating animals for food,
The Making Of The Fittest
Episode 5
14 minutes 56 seconds
Grade Level: 10 - 12
 A large bird flying through the sky. Spanish captions.
The Making Of The Fittest
Episode 6
10 minutes 29 seconds
Grade Level: 10 - 12
Blood cells flowing through a vein. Spanish captions.
The Making Of The Fittest
Episode 7
14 minutes 6 seconds
Grade Level: 10 - 12