Galapagos Marine Iguanas

Marine iguanas sneeze frequently to expel salt from glands near their noses. The salt often lands on their heads, giving them a distinctive white wig.



They are either black or dark grey in color except when males are near mating seasons when they turn shades of red and green. The dark pigment in the skin helps shield the animals from the effects of ultraviolet rays. It is also useful in warming the body.



With one breath, the iguanas can reach depths of 30 feet. Marine iguanas are cold blooded, however, and can only stay in the water for about 10 minutes.

Marine iguanas are cold blooded, however, and can only stay in the water for about 10 minutes.

Guppy Simulation

1. Q: If being flashy and colorful attracts predators, why do you think guppies are so colorful?
A: It helps to be colorful because it helps in the mating process. In the end, there will be more colorful guppies than ones that have been eaten because they repopulate more than the drab ones.

2. Q: After viewing the guppy gallery, pick the fish you find most interesting. What is the fish's common name, scientific name, and origin.
A: The common name is guppy or millions fish. The scientific name is Poecilia reticulata. It's origin is Peru.

3. Q: After viewing the predator gallery, pick the fish you find most interesting. What is the fish's common name, scientific name, and origin?
A: The common name is Pike cichlid. The scientific name is Crenicichla alta. It is originated in Trinidad and Latin America.

4. Q: View the guppy's habitats, what habitat conditions would affect the predator populations?
A: The Quare River would affect predators because they sometimes do not contain water year round. Trinidad's Aripo River can contain many guppies, as well as many hungry predators. Some small dams keep predators from moving upstream. Many predators find their way into shallow pools. Some dams restrict predatory fish movements.

5. Q: Who is John Endler? What did he study and where did he study it?
A: John Endler is an evolutionary biologist who studies guppies. He studied guppies from different streams, even among guppies living in different parts of the same stream.

6. Q: For each of the three stream areas, describe the guppy coloration.
A: 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. Q: 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)
A: Female guppies are choosing to mate with the most brightly colored males, giving those males a higher probability of passing their genes on to the next generation.
 
8. Q: Describe how predators influence guppy coloration.
A: Predatira influence guppy coloration because some predators may find it easier to prey on drab or bright colored guppies. This can increase or decrease either coloration.

9. Q: Was your hypothesis correct?
A: My hypothesis was mostly correct, having three of the five trials favor brightest or bright guppies. I could also be incorrect because the last trial was 100% drabbest.

10. Q: What does it mean that "male guppies" live in a crossfire between their enemies and their would be mates?
A: It means that the bright guppies have to choose between mating or not being eaten.

11. Q: Why do you think guppies in different areas of the stream have different coloration?
A: Some guppies in different areas of the stream have different coloration because of camouflage, mating, and other important variables.

12. Q: What would happen to mostly drab guppies that were placed in a stream with very few predators.
A: Drab guppies would most likely dominate because they can easily camouflage from predators, even though they are not the first choice to mate with.

13. Q: What would happen to brightly colored guppies that were placed in a stream with many predators?
A: They could either dominate, by repopulating quickly, or die off, by attracting predators.

Biodiversity

1. One way in which preserving biodiversity locally might have a global effect are if all internationally traded organisms (whether alive or dead) were monitored, regardless of whether they are currently listed as threatened. This would allow countries to identify emerging markets and act early enough to prevent depletion.

2. Habitat destruction and loss of species effect more than just one area because if one species in a habitat is diminished, then the predator of that animal is left with no food. The predator then must move to a new habitat to find food, completely messing up that habitat's food chain. This would also happen if the habitat had been affected by destruction of some kind.

3. Preserving biodiversity enhances the life of people by giving us more resources to use, mainly food, but also trees, water, and even clothing sometimes. It will also enhance the lives of future generations by providing enough resources, and even more than enough resources, for them to rely on.

Extra Resource:

http://www.enchantedlearning.com/subjects/rainforest/Animals.shtml