4.07 Genetic Park: Genetic Evolution

Who wants a frozen banana from the healthy foods snack shack before we go to the aviary? I bet you didn’t know that grocery store bananas are genetically identical to each other. That’s right, Chiquita bananas are grown using a method of cloning so that they are all the same. Why use cloned bananas? Cloned bananas are VERY predictable for the growers and this predictability makes it real easy to decide when to fertilize, irrigate, pick, and ship those bananas.

Head out to the Web and check out a current urban legend. Read it over... it is one of those things that should make you say "Hmmmmm."
Banana Peel: Bananas extinct in 20 years?

In this activity you will: describe factors that can cause genetic diversity summarize the effects of natural selection on populations learn the importance of mutations on genetic diversity and its role in adaptation hypothesize why some bacteria evolve to resist antibiotics

What do you get if you take the variety out of an animal's sexual reproduction? You guessed it...a Clone!

While bananas and other plants have been cloned for centuries, mammals could not be cloned until recently. In July of 1996, a sheep named Dolly was successfully created from one of her mother's cells resulting in the first cloned mammal. Normally, sheep reproduce like we do, a sperm meets an egg and presto the combination of the chromosomes makes a lamb. This time, it was all done in a chemistry lab. Dolly was an exact copy of her mom - no genetic diversity, much like those bananas in the article you just read.

Check out the following files on Dolly:

Cloning Conundrum

Creating a Cloned Sheep Named Dolly, Deborah Barnes, Ph.D.

Unfortunately, Dolly had to be put to sleep on February 14, 2003, after developing a progressive lung disease. The type of lung disease Dolly developed is common in older sheep but she was only six years old. Was this bad luck or a problem with cloning animals? Dolly's death will refuel the intense debate over the health and life expectancy of cloned animals.

Cloning animals continues to be a very controversial topic because if you can clone a sheep today you can expect a future to include trying to clone humans. Enough of the politics, let's go to the aviary to see some of the world's most beautiful fowl.

Move on to the BioVenture tab to continue this activity.