Galapagos Giant Tortoise

Giant Galapagos tortoises usually can live up to 150 years and 175 years is the record for the longest living land mammal ever, and it was set by Jonathan the Giant Galapagos Tortoise.

• A Giant Galapagos Tortoise can live one year without food or water and still maintain the weight of 550 pounds.

The Giant Galapagos Tortoise sleeps for 16 hours a day.

The original ancestor of the tortoises was probably of normal size and evolved into the present day giants after its arrival in Galapagos. This is due to a phenomenon seen in many island ecosystems where gigantism evolves because there is no longer any need to hide from predators and because there are no other similar animals to compete with for food. Once the tortoises spread around the archipelago, they evolved on their isolated islands into the different races we see today, some with domed carapaces (shells), and others with saddleback carapaces. The unusual saddle shape is believed to have evolved several times on different islands, showing that it must be a very successful design for life in Galapagos.

Guppies

1. If being flashy and colorful attracts predators, why do you think guppies are so colorful?

Guppy populations are evolving to more closely match or stand out from their environment.

2. After viewing the guppy gallery, pick the fish you find most interesting. What is the fish’s scientific name, origin and average size? Describe the coloration of the fish you chose.

Guppy or millions fish, Poecilia Reticulata, Brazil. Large patch of shiny black coloration on the top of its back, yellow, white, green, and red spots throughout the bottom of the bottom and fin.


3. After viewing the predator gallery, pick the fish you find most interesting. What is the fish’s common name, scientific name, and origin?
Fat Sleeper, Dormitator maculatus, Southern North America, Bahamas, and Latin America
4. View the guppy’s habitats, what habitat conditions would affect the predator populations?

Some habitats that would affect that predator population most would be the dams which keep out predators so they can't reach the guppies and some of the smaller deeper lakes/ponds would keep lots of guppies as well as predators.


Endler’s Discovery and Variations of Guppy’s in Pools

5. Who is John Endler? What did he study and where did he study it?

John Endler is a professor who is also a ethologist and evolutionary bioligist noted for his work on the adaptation of vertebrates to their unique environments
6. For each of the three stream areas, describe the guppy coloration:

Pool 1: Brightly multi-colored with large spots. Pool 2: Medium coloration on body and tail, with medium-sized spots. Pool 3: Drab coloration, very small spots concentrated near tail.

7. Develop your own hypothesis about guppy coloration. The hypothesis should answer the questions: Why do guppies in different areas of the stream have difference in coloration? (You can choose from the list on the simulation, or make up your own)

Predators are causing guppy generations to become more drab by preying on the most brightly-colored individuals and eliminating them from the gene pool.




Guppy Simulation

	% of Brightest Guppies (10 generations)	% of Bright Guppies (10 generations)	% of Drab Guppies (10 generations)	% of DrabbestGuppies (10 generations)
Trial 1 Guppy: Even Mix Predators: 30 Rivulus	42%	25%	28%	5%
Trial 2 Guppy: Even Mix Predators: 30 Rivulus, 30 Acara	43%	41%	16%	0%
Trial 3 Guppy: Even Mix Predators: 30 Rivulus, 30 Acara, 30 Cichlid	2%	0%	8%	90%
Trial 4 Guppy: Mostly Bright Predators: 30 Rivulus	75%	20%	4%	1%
Trial 5 Guppy: Mostly Drab Predators: 30 Rivulus, 30 Acara, 30 Cichlid	0%	0%	7%	93%

Summary

8. Describe how predators influence guppy coloration.

Predators influence guppy coloration because the predators eat the brightest most colorful guppies therefore the guppy coloration is slowly leaning towards the drab side.

9. Was your hypothesis correct, use your data to justify your answer.

Our hypothesis was correct because the predators eating the brightest fish cause the population of them to fall while the drab population rizes.

10. What does it mean that “male guppies live in a crossfire between their enemies and their would be mates”?

It means that male guppies while being bright and attracting mates, they also attract predators so they are stuck between mating and being pray to other fish.


11. Why do you think guppies in different areas of the stream have different coloration?

The further down the stream the drabber the guppies get because the lower they are the fewer predators that are able to reach that area. If you go to the top of a stream fewer predators will be there so there will be more bright guppies.


12. What would happen to mostly drab guppies that were placed in a stream with very few predators?

They would most likely survive a long time because they won't stand out as much as other bright guppies.

13. What would happen to brightly colored guppies that were placed in a stream with many predators?

They would most likely be eaten soon after and the drabbest of those guppies would survive the longest time.

Biodiversity

Q:What are ways in which preserving biodiversity locally might have a global effect?
A: Preserving biodiversity in a local way can have a global effect, If other people see how we are preserving biodiversity then they will want to help to. If we preserve biodiversity in Bangladesh and India on a local level then less trees would be logged. If less trees are logged there then there would be more air for us to breathe and less death in India from the floods. Less people dying and more oxygen is good. :)

Q: How do habitat destruction and loss of species effect more than just one area?
A: If all of the trees are cut down in India, then not only would India be effected,but so would a lot of the world. India would have major flooding and they wouldn't have much wood to make wooden products out of and to export them to other countries. Other countries wouldn't have any wooden products imported or exported.

Q: How does preserving biodiversity enhance the life of people?
A: Preserving biodiversity can enhance the life of people because we might/ most likely be able to find cures for cancer, AIDS, etc the cone snail is a great example. The cone snail's population is dropping and if it becomes totally extinct then bye-bye cures for diseases. We would be able to save lives.

Other sites used:
http://www.suite101.com/article.cfm/science_students/88655